Introduction to Psittacine Pediatrics

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Introduction to Psittacine Pediatrics

Robert Clips ham, DVM*

Pediatric avian medicine is frequently held synonymously with avicultural medicine because of the intimate relationship and common goals held with nondomestic aviculture. Babies are the ultimate product for aviculture, and the sale or successful breeding of those offspring is the hallmark of a successful avian medical management program. Pediatrics require a thorough knowledge of pet bird medicine, personal avicultural experience, a first-hand knowledge of the biology and behaviors of each individual species, and an appreciation of the extreme need for tenacious attention to detail as well as a resolve for expedient care delivery. Baby psittacine birds grow quickly, are highly dependent on their environment, and have great demands being placed on them for performance. This group is altricial but attains a substantial degree of independence on fledging, between the ages of 8 weeks and 6 months of age, at which time the bulk of pediatric problems have appeared or passed in significance. Accordingly this article specifically addresses the needs of psittacines because they are the overwhelming volume of cases presented to avian practitioners at this time. Since the scope of this subject necessarily covers a vast range of medical, surgical, management, congenital, and environmental topics, it is well beyond the limits of this article to present more than a fraction of the possibilities. A few major categories are offered as an introductory text. PRINCIPLES Pediatric medicine should be separated into four distinct categories: (1) embryonal; (2) perinatal (hatching); (3) neonatal (infant); and (4) juvenile based on development and the accompanying physiologic status that are inherent for each of these levels, as the degree of fragility and dependency decreases with time while the variations in disease processes increase in scope as a result of the rapidly developing anatomy and body mass of the young birds. Each of these four stages has unique aspects and diseases, many of which are only recognized to date and have no explanation as to their etiology or successful treatment as of the present time. As with other less evolved species, such as reptiles and amphibians, avians must achieve great gains in their early development to sustain their survival, based on parenting habits and susceptibility to predation prior to fledging. One item that has begun to make itself abundantly clear in the past few years *California Exotics Clinic, Simi Valley, California Veterinary Clinics of North America: Small Animal Practice-Yo!. 21, No. 6, November 1991

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is that an overwhelming portion of the diseases and deformities seen as clinical presentations have their origins in mismanagement. 5--7 , 9 • 10• 22 Because of the fact that the entire embryonal development is totally dependent on the nutrients and tissues conglomerated in a very short period of time (approximately 24 hours) in the oviduct and that no active maternal influence can be manipulated from lay to hatch, the status of the hen takes on enormous proportion as to the health and survival of the chick'· 6 • 8 • 9 • 11 Nutrition, disease, stress, infectious agents, and environmental influences (i.e., chemicals, temperatures) can have their effects mirrored in greater magnitude in the chick since the developing tissues are incorporating or using both necessary nutrients as well as any other substances being packaged into the egg once it is laid. Since the cell division and differentiation process is ongoing at a high rate, the detrimental influences of any teratogen, nutritional deficiency, or egg-transmitted disease can have an extraordinary effect on the offspring well above that of the parent bird. Furthermore, environmental influences such as incubator temperatures and humidity levels as well as egg positioning, incubator sanitation, specific pathogen control, light intensity exposure, and pipping vocal exposure can all influence the timing and ease of hatching. 1· 10· 12-14· 20• 23 These aspects are well known to poultry hatcherymen, and ignoring any of these standard aspects of ordinary husbandry can lead to congenital defects or neonate disease outbreaks of epidemic proportion. It suffices to say that the axiom of an ounce of prevention is worth the proverbial pound of cure applies aptly to psittacine incubator management as well. It is unfortunate that both aviculturists and veterinarians alike continue to underestimate the value of fertile, unhatched eggs, as the few square feet and its contents within an incubator usually overshadow any comparable space on the farm in terms of productive dollars over any other site. 7 • 8 · 12• 20 Incubator management is not as well understood as we would like simply because most aviculturists do not keep records and do not contract for veterinary services. Therefore, their observations are not documented and analyzed to promote overall industry progress. Most veterinarians do not appreciate the importance of incubator and brooder function or their management well enough to emphasize the need for attention to detail or to draw it to the aviculturists' attention. This, coupled with the fact that the diversity of species requires an intimate appreciation and working knowledge of the unique aspects of each species' natural habitat, nesting behaviors, and disease susceptibility, makes criticism of any current program difficult. There are, however, two ongoing circumstances that require evaluation. First and foremost is the reality that global politics and ecologic issues regarding threatened species conservation are a vital concern. 4-
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of breeder nutrition, incubator design, brooder thermodynamics, and infant food management were addressed as a matter of routine, rather than retrospect. The following items should be targeted as areas of investigation and education by those veterinarians wishing to develop or enhance a pediatric medicine section for their clients. Client education should figure prominently into these efforts as pediatric patient recovery can be improved by sophisticated aviculturists that are knowledgeable in the general care as well as after care of treated infants and juvenile birds. It is tremendously disappointing to rescue a valuable baby successfully from an ominous disease only to be presented with an equally serious relapsed patient a few days later due to a lack of communication or appreciation of the disease process on the part of the owner.

FUNDAMENTAL TARGET SUBJECTS FOR AVIAN VETERINARIANS The following areas of concern should be kept in the mind throughout the remainder of this article: Overall aviary management. Sanitation-aviary, nest box, incubator, nursery, and kitchen. Incubator design and nest box function. Brooder design and function. Nursery design and management. Pediatric nutritional requirements. Interaction of stress and disease in infants versus adults. Pediatric immunology and disease resistance.

AVIARY MANAGEMENT The health of the breeder pairs should be directed under an aviary medical management plan developed by the owner and supervised by the veterinarian that defines both the long-term and the short-term goals of the farm as well as the current state of flock health. The areas of disease identification, nutrition, routine disinfection, flight construction, quarantine and isolation facility location, and record systems should be addressed in an overall plan that is customized for each producer. 1• 5 The incubator room should be located nearby but separate from the nursery, so that disease transmission can be prevented. The nursery and hatching areas should have limited physical entry from the remainder of the grounds to prevent the casual introduction of disease or handling of eggs and chicks by workers or visitors. Farm protocol must mandate the exclusion of all off-site birds and eggs from other avicultural sources until they have been held in quarantine for at least 60 days and up to possibly 180 days. 5· 6· 19· 20 This precludes the occasional purchase or sharing of eggs or chicks without completely separate facilities and crews and, therefore, places this option out of range for all but a few large farms. The introduction of one of the significant viral agents or vertically transmitted diseases, such as Mycoplasma, makes for a grim and lengthy scenario. The practice of renting egg space in incubators or hatchers, or the communal sharing of hand feeders between farms, is considered to be maintaining a biologic time bomb. A closed facility is the only method of maintaining a status quo without the introduction of unknown variables. The opportunity for potential disease and management setbacks is ample enough within the closed system without the introduction of uncontrolled diseases on a regular basis. The nutritional status of the breeding pairs should be evaluated for optimal

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conditions promoting the production of viable offspring. Specific species require special attention as to dietary intake because certain psittacine species are prone to impairment of reproduction when this is overlooked. In particular, Table 1 summarizes well-documented problems. These are only a few of the problems seen as classic reproduction diseases but once again are all too often treated as spontaneous medical problems with surgery or drugs and not as mismanagement. Probably the single greatest cause of infertility, early embryonic death and early infant mortality lies in the combination of poor breeder nutrition and nest management. Improper incubation and hatching mismanagement only serve to raise the numbers of preventable production losses during or after incubation. Careful examination and correction of poor diet, inconsistent food and water sanitation, and disturbed nesting pairs reveal a goodly number of causes th,at will otherwise defY diagnosis or correction and lead to unfounded accusations of misdiagnosis or noncompliance between client and veterinarian, leading to an often futile search for a better curative drug or yet another source of veterinary care. There are several well-known guidelines within which the aviculturist may define his or her specific program depending on long-term goals. There is some controversy as to whether the chicks should be artificially incubated, parent hatched, or parent raised for the first 2 weeks and at what time to start hand-feeding chicks. Brooding hens make excellent incubators because the hen's brood patch is sensitive to changes as little as 0.1° F at the eggshell surface. The bulk of available commercial incubators are not. Hens are also tireless, are generally careful with their eggs, and rotate their eggs regularly during every 24-hour period. Many incubators must rely on manual turning of eggs by the aviculturist. Hens can compensate for great fluctuations in ambient temperature and humidity, given the proper shelter, nest box, and access to humidity. Many incubators are not well enough insulated or electronically sensitive or provided with hygrometers to accomplish these critical tasks. On the other hand, egg production may be substantially increased by stimulating pairs to clutch again to compensate for eggs lost to pulling for incubation and therefore yield total egg numbers far in excess of those brooding clutches naturally. This is usually desirable for most aviculturists. To insure some level of success, the aviculturist should purchase a high-quality incubator (Humidair, Grumbach) and have the electronics tested by a person qualified to evaluate the reliability of the incubator's function. 16 Evidence shows that parent-raised offspring are more likely to produce viable

Table 1. Dietary Considerations in Psittacine Species SPECIES

CONDITION

Large Amazons, Rosellas, Rose-Breasted Cockatoos African Greys

Obesity

Eclectus

Hypovitaminosis A, hypovitaminosis E Hypovitaminosis D 3, hypocalcemia

All All

Hypocalcemia

Protein deficiency

DISEASE

Egg binding, reduced fertility, cardiovascular collapse Egg binding, pathologic fractures, seizures, early embryonal death Infertility, early embryonal death Thin shells, embryonal dehydration, pathologic fractures in neonates, stunted chicks Infertility, embryonal death, embryonal dehydration, stunted chicks, poor doers

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eggs and offspring than hand-reared parents (based on studies in cockatiels by Roudybush at University of California, Davis). This does not usually apply to those farms producing chicks for the pet trade but may be an important consideration for those chicks to be held back as breeder replacements or for sale strictly as breeders to other aviculturists. Hatching and hand-feeding chicks from day one requires strict attention to scheduling and nutrition. Any casual lapse in food handling, feeding technique, or schedules as well as brooder care of these altricial birds can have rapid and serious consequences. Chicks left in the nest for approximately 2 weeks or just before the eyes open tend to have greater weight gains, higher survival rates at weaning, and proportionately free the aviculturists' time for other tasks. Pulling the chicks before visual parent recognition allows for greater cooperation in the nursery and reduced stress. This assumes that the parents are not prone to destructive behavior or chick abandonment. Parental stress, overcrowding, interpair or interspecies aggression, and nest box di'sturbance by feed crews or daily egg checks frequently lead to cold, discarded starved, or cannibalized chicks. Once this scenario has set in, a commitment to egg pulling on improved management of the flights must be addressed, or the entire program will have consumed enormous amounts of time and money with no salable product as compensation.

SUPPORT SYSTEMS Psittacine embryos, neonates, infants, and to a lesser degree juveniles are dependent on artificial means for sustaining life. Heat, fluid balance, nutrition, predator protection, and shelter from the elements are all actively provided for by the natural parents. Because psittacines are hatched at an underdeveloped stage (nidicolous) and remain under parent care until fledged and weaned, the aviculturist must assume the responsibilities of incubation, brooding, food gathering, cleaning, thermal control, defense, and training for self-sufficiency. These are no simple tasks and are best accomplished by developing a sophisticated nursery system, which assumes the role of the hen with the support of the aviculturist. 6· 20• 23 It is far more economical to construct and develop a highly efficient traffic flow-planned nursery, with a built-in capacity for expansion, rather than accumulate a series of soon defunct and time-consuming step-up devices. The overall cost is lower, and, time, which is the definitive component of the pediatric aviculturist's success as well as a source of ultimate defeat in a blossoming production farm, is conserved. It is wise to base all plans on the assumption that the success you hope to achieve will prevent you from ever running out of money, but no level of success or failure will circumvent a lack of time or energy. Many production facilities have closed because of nurseryman burnout after years of struggling to achieve finally a high level of chick production. The following items are the foundations for at least providing for some guaranteed success: incubators, brooders, diets, sanitation, and management.

BROODERS This is the heart of the operation. It should be pointed out that incubators are designated for embryologic development, whereas brooders are reserved for infant care. Without a properly built and maintained incubator, production only goes as far as the collection of eggs. This is also probably the single most underappreciated source of "infertility" and chick mortality on the farm due to a lack of understanding of avian embryology and prenatal diseases by aviculturists and veterinarians alike.

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Most breeders shop for incubators as if they were cars. Price, size, color, dials, and reputation are all given improper priority. I estimate that a typical breeder in my practice in business for an average of 5 to 7 years with 15 to 25 pairs of medium to large-sized birds will have a minimum of 3000 to 4000 dollars' worth of potential baby sales at any one time during an average breeding season, and yet many aviculturists insist in buying incubators based on price alone. A well-managed farm should have a minimum of three incubators: one for incubation; one for the last 48 hours of incubation (hatcher), where lower temperatures and elevated humidity are required; and an idle one to serve as a backup in the event of mechanical failure. A spare power generator has also saved many of my clients thousands of dollars in lost eggs at times of unexpected blackout. Incubators should have sophisticated electrical components, preferably solid state. Many popular brands should be technically upgraded so that thermal control will be within 0.1 o F. Power surges and unreliable power quality should be modified electronically. Automatic turning devices should be sturdy and smooth, with cushioned grids or bars. Make sure the motors are of sufficient power to turn many trays loaded to maximum weight for weeks to months at a time. Trays should be set so that each egg is properly located in the cup or bar pattern to prevent uneven vibration, such as is the case when large-sized eggs allow the smaller ones to roll uncontrollably. Hatch rates can be significantly increased by slightly elevating the large end of eggs, so that the air cell is at a 45- to 90-degree angle. 23 The incubator should have as simplistic and clean a design as possible to prevent the retention of dirt, fungus, and other pathogens, especially motile bacteria such as Salmonella and viruses. 2 · 7· 17 Embryonal disease concerns are not necessarily identical to those of infant or adult birds, and the undeveloped chick's tissues are in a high rate of growth and certain viruses will be provided a unique opportunity to express themselves that is no longer available in the fully developed chick or juvenile. 10 This viral expression can be diverse and seen as embryonal death, defective growth and organ development, or weakened offspring. These diseases are largely unidentified as of yet and certainly underinvestigated. They may be responsible for a significant portion of losses in the avicultural industry while simultaneously being totally unsuspected. Many such agents are documented in similar circumstances in the poultry industry involving decreased egg production (i.e., adenovirus-127, "the egg drop syndrome virus;" various reoviruses; and parvoviruses). The specifics for viral screening and detection are not worked out, and therefore both eradication and diagnosis must be currently replaced by meticulous attention to detail and scrupulous sanitation. Viruses of concern for vertical transmission in psittacines are not conclusively documented to date but include psittacine feather and beak virus (Dimunavirus), reoviruses, and parvoviruses based on field observations in which artificially incubated, hand-reared infants expressed those viruses. Eggshell contamination must necessarily be included in a list of possible sources until definitive proof surfaces as to transovarian infection of embryos or some other route of vertical transmission. The role of Mycoplasmas must not be overlooked as a potential possibility owing to its extreme prevalence as a vertically transmitted infectious agent. 2 • 11 • 19 This class of agents is responsible for one of the foremost causes of morbidity and financial loss in the modern poultry industry. The ability to determine the status or impact on psittacine reproduction remains unknown because of the difficulty in propagating Mycoplasmas under laboratory conditions. It is proposed that the formation of a readily available source of species-specific psittacine growth medias, particularly cell lines, might formidably change this current impasse. Until then the status of these organisms remains open. Mycoplasmas have been documented in psittacine disease, but their role is yet undetermined as to scope or pathogenicity. Despite the obvious visible effects of bacterial and fungal agents when noted

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in chick mortality or weak hatches, the incidence of these agents is generally considered to be very low overall. An intensive survey by Flammer while at the Avicultural Institute of Newhall, California, of infertile and dead in shell (DIS) psittacine eggs revealed zero presence of occult bacterial or mycotic elements, even after allowing the eggs to remain under incubation 5 to 10 days past assumed lost of viability. Those cases in which frank fungal growth, foul odor, or dark unabsorbed yolk sacs occur are usually traceable to the causes of lack of sanitation, gross fecal contamination of set eggs, and invasion of the protective shell layer especially by sharp parent nail punctures. Experimental field efforts with the use of relatively nontoxic parenteral antibiotics (piperacillin) by Fudge and MacDonald revealed some encouraging results when injected in suspected embryonic bacterial infections during incubation. Therefore, incubators should be washed then disinfected with a broad-spectrum agent or fumigated for a high degree of sanitation. 7 Fumigation with formalin and potassium permanganate is currently recommended as per poultry industry protocol between each incubated setting. Caution should be exerted because the fumes are toxic to birds and aviculturists alike. The practice of fumigating eggs before the initiation of artificial incubation has been used in cockatiel eggs (Roudybush), but is not practiced with any significant regularity in other psittacine species because of reports of decreased hatchability in the poultry literature. The practice of renting or sharing incubator space with other aviculturists is to be strongly discouraged because embryonal die-offs are well documented and promote the spread of significant viral diseases such as polyomavirus and reovirus flock to flock. The introduction of serious flock diseases, such as psittacine feather and beak disease, have been traced to the introduction of contaminated eggs onto ranches, especially through fecal material not cleaned from shells. Egg dipping in a standard disinfectant bath protocol will assist greatly. It is recommended to inspect eggs for contamination before entry to the hatcher, and the separation or elimination of certain species such as budgies, cockatiels, and conures is highly advised to guard against cross infection by Mycoplasma, Chlamydia, and Pacheco and polyomaviruses. 5 Brooder Design and Function It is important for clinicians and aviculturists involved in domestic propagation to understand the basic thermodynamics of a working brooder to deliver maximum care benefits. Proper environmental control is secondary only to fluid balance and nutritional support, and an improper brooder environment directly and adversely affects the parameters of the first two categories if not recognized. Cold chicks do not demonstrate proper gut transit times and require additional calorie support. Dehydrated patients do not possess proper fluid compartmentalization and do not efficiently process pharmaceutical agents in the intended pathways. Peripheral circulation is severely compromised, and the uptake of subcutaneous and intramuscular drugs is delayed. Therefore, this is a fundamental form of preventive medicine, and the employment of proper environments eliminates the use of unnecessary pharmaceuticals that are all too frequently relied on to correct pathophysiologic conditions diagnosed in intensive care patients both on admission and during hospitalization. Many cases of stunting, poor weight gain, crop stasis, and slow gut transit can be remedied simply by correcting brooder environments and are all too often treated to their detriment with antibiotics or antifungals, many times accelerating acute renal compromise, creating iatrogenic nephrosis. 6 To understand the internal environment of a brooder, it is important to understand thermal environments on a conceptual level. It is perhaps easiest to visualize the earth's atmosphere as represented by a color-coded mockup with the various wind patterns and relative cooling and heating trends with their associated

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high and low pressure regions. This mental picture is familiar to us on the daily weather reports. The same phenomenon takes place on a much smaller scale within buildings and in turn within each individual room on an even more subtle level. It is critical that the clinician understand that rooms possess microclimates with temperatures varying as much as 2°F to 4°F from corner to corner, with similar variances in humidity. The same areas of a room can vary one to multiple degrees of temperature night to day, particularly along outer walls of buildings. This is mostly dependent on the quality of the temperature control of the room, through the outside ambient temperature and climatic conditions, insulation, building materials, air flow, and appliances that affect overall room conditions. Microenvironment Control Medical brooders contain a microenvironment that is similar in nature to room environments and is also affected by the immediate surrounding external conditions. The degree to how stgnificantly the surrounding environment affects the internal environment depends on their respective differences. The greater the difference of the surrounding environment, the greater the influence. In an attempt to minimize this influence, the design must incorporate efficient insulation, either in the form of a wall that has inherent insulation capacity or as an insulation blanket applied to the walls themselves. Those elements that assist the brooder in maintaining temperature are active heat production devices, adequate heated air flow, and heat sinks. The elements that serve to defeat insulation are excessive air/heat leaks (ventilation) and improper brooder design. Because it is necessary to incorporate a combination of these elements, a balance of heat supply, air flow, and ventilation must be achieved to maximize each in relation to the needs of the patient. One of the greatest lessons that we learned was that ventilation is given far too much priority in relation to patient requirements. The air volume of most brooders large enough to accommodate the average psittacine patient contains sufficient oxygen to support the patient for several hours without any ventilation at all. The tidal pulmonary volume needed to support life is the bottom line value for ventilation requirement, and this can be achieved with a very small cross-sectional opening in comparison to the average perception of veterinarians and commercial designers. It is helpful to consider the brooder as being a pond, with the ventilation port as the stream and the lungs as the dam gate. It is necessary only to fill the reservoir with oxygen as fast as it is being used. Since the respiratory capacity and oxygen uptake demands vary from patient to patient, it is important that some flexibility exist, and therefore ventilation port size controls are desirable. Forced air environments are more desirable than those of still air brooders because moisture is evaporated more efficiently and temperature gradients are minimized. The common temptation is to provide a strong air flow source for the chamber. However, the increase in new air introduced directly counteraffects the benefits of stable heat control. It is therefore ideal to strive for a brooder fan that mixes the air at a rate just slightly greater than normal convection currents. More air flow is not necessarily better. When the air flow is excessive, the demand for superior insulation and heat retention devices such as heat sinks rises dramatically. We have found that the air inlet port on nearly all blower units that we have needs to be recut and significantly reduced from eight half-inch holes to only three quarter-inch holes in our largest unit, or the desired temperature of 85° to 90° F and 60% humidity could not be achieved under normal room conditions when a 32 cubic foot/min (CFM) fan was used because of the excessive air intake condition. The entry ports were entirely sufficient to sustain proper oxygen, heat, and humidity levels. Very small variable factors become critically important as one seeks to exert ultimate control over a finite volume of space. 16

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Humidity has also been clearly demonstrated to be a critical factor in proper pediatric support. The higher the temperature and the greater the air exchange, the greater the rate of patient insensitive water loss. It is important to provide a humidity source that is constant and safe. Water cups placed on the floor can be used but may also represent an unacceptable danger to infants or weakened individuals that may drown, or they may become a source for contaminated drinking water when feces, food, or body discharges are introduced. Many climates in the United States, such as in Southern California, have relatively low ambient humidity (approximately 30%), and it is difficult to elevate internal humidity levels without crowding the patient when solely using floor cups while attempting to achieve effective ventilation simultaneously. Experience has led to a preference of using an elevated, built-in water container with a variable surface area option. Wet sponges placed in holding trays may also be used because. of their large inherent surface area and constant evaporation rate, but sanitation control and fungal spore production are a concern when dealing with compromised patients and cross contamination between rapidly rotating hospital cases. Multisectioned trays with graduated walls seem to work the most efficiently for both space conservation and changing ambient humidity levels. Triangular crosssectional configurations or multisectional rectangular troughs have both been used successfully. These are placed at the upper levels of the chamber to maximize usable floor space and to prevent patient drowning. The trough is also sloped along its long axis such that the water depth is greater at one end, further enhancing water surface variability. The triangular troughs tend to be more difficult to clean than rounded or flat bottom water trays. Nolvasan or a similar nonfuming, nonirritating disinfectant assists in reducing fungal and bacterial bloom when added to the water. It is ideal to place the water source directly in the air flow path if the brooder design will allow for this to maximize humidity production. I recommend that 55% to 80% relative humidity be used to prevent patient dehydration, depending on the age and species involved. Rain forest psittacines live in a constant 85% humidity environment, but this level may be difficult to achieve in temperate zones. Some marine or tropical locations may have a reverse problem with excessive humidity, unless the building is insulated and dehumidified. In these cases, warmed, forced air will assist to reduce humidity levels. An accurate hygrometer is fundamental and can be purchased as part of a combined unit. These units should be positioned inside the front panel for easy viewing and away from curious beaks inside a shielded retainer slot. Again, relative brooder humidity, like temperature, can be affected by the external room environment. Room humidifiers have been successfully employed to augment the moisture level of room air entering the chamber to achieve the desired affect. This may be economically advantageous if a large number of brooders are being used, both from a purchase as well as a maintenance standpoint. Stress Reduction One of the initial factors that prompted us to consider developing a new brooder design was the fact that many of the larger patient species, such as macaws, were severely curtailed in their movements in the old-style human pediatric (i.e., Armstrong care units) chambers and most commercially available bird brooders. Because a significant percentage of our patients are parent-raised breeders, this situation would become increasingly more stressful as the patient's improved strength and awareness of captivity restrictions increased with a successful therapy response. Stress reduction should be a focal point in patient care and should be part of client education efforts in promoting chick production and avicultural preventive medicine programs. Yet, veterinarians have been one of the greatest offenders of their own guidelines. It is paramount that the patient's need for space,

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security, and free movement be addressed to promote healing as well as to gain valid observations of treatment response trends. We questioned what increase in recovery rate we could accelerate if a brooder could be designed to provide separate perching, movement, and feeding areas for these breeders. Considering that a Green Wing Macaw can easily occupy 3 square feet at rest plus room for tail turning, this could entail quite some space. We developed two models, the smaller one being approximately (14" X 14" X 18") 4 cubic feet for small psittacines (up to small Amazon size) and the other being 36 cubic feet (3' X 3' X 4') for large psittacines. To promote psychological security, all the walls and the top are constructed of opaque acrylic except a clear acrylic front panel. The sides are grooved to accept divider panels in the larger unit should the space present be too large for a particular patient or several members of the same clutch be housed simultaneously. This lack of visibility prevents patients from feeling threatened by other birds and movement of staff members but allows for rapid patient assessment. Visual security is a high priority for stress redtfction. The floors are constructed of the same material with each unit having a powdercoated aluminum plate that slides into a track and serves as a heat sink. This aluminum plate is lightweight, resists scratching, and is nontoxic. It serves to absorb and trap heat under the newspaper substrate. The plate acts as a heat bank and provides heat by conduction to the patient's feet, especially when a chilled bird is placed into the preheated chamber. This is more efficient than warming the patient by air conduction alone, as the large venous plexi present in the feet carry the heat to the body core more quickly. It also releases heat into the chamber air by radiation once the lid has been opened. The delay for chamber environment reheating can be reduced from 10 to 20 minutes per intrusion to essentially no fluctuation with this device. The internal temperature remains stable for up to 30 minutes after the unit is turned off even with the lid open under normal room conditions. Since critical patients may simultaneously require both frequent examination and drug administration as well as constant heat influence, the heat sink eliminates a serious physiologic stress unavoidable with conventional brooders. It is important to remember that aluminum expands with heat and that the holding track not be built too tightly but not too generously either because side drafts will be created. The thickness of the acrylic wall and top material should also be considered when designing a brooder. Acrylic is not the only material available but does have the advantage of being available as both colored and transparent sheets, is a fairly good insulator, is waterproof, can be disinfected, seals well with special adhesives, is strong, and lends itself to conventional construction techniques. There is an inherent trade-off between insulation capacity in the thick sheets and the inherent weight and cost increases that accompany them. Heavy gauge acrylic is expensive and must be purchased in 4' X 8' sheets. We have found the%" material is a good trade-off between cost and insulation ability; however, thinner sheets can be used to the same effect when room construction permits good thermal control. All devices, including the monitoring instruments, heat sink, perches, heater control fan, and food cups, are removable so that the entire chamber can be completely submersed for disinfection. All walls and surfaces are designed to be uncluttered to minimize potential pathogen retention. The accessories and hardware within the unit are plastic or metal to minimize maintenance and contamination problems. It is important for avian veterinarians to recognize that as bird owners and aviculturists become more responsible for establishing disinfection programs and quarantine protocols for themselves, avian clinics become relatively more significant origins of cross contamination between breeders. Any degree of pathogen retention, especially viruses, can have devastating implications in client breeder facilities. Metal molding, mesh grids, exposed wires, and chains are difficult to

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clean. It is also expensive to pay staff members to disinfect brooders properly. Our staff requires 30 to 40 minutes to disassemble and scrub an Armstrong chamber properly after each patient dismissal. The labor saving alone pays for the superior equipment in 1 year's time. Each brooder is placed onto a steel tubular frame built on castors so that the units can be relocated within the clinic according to each particular case's requirements. This greatly assists in avoiding chipped corners and scratched face plates because the large units can be formidable pieces of equipment to move manually. The financial investment made in the 10 units manufactured was substantial in terms of both time and capital. Case review records revealed that our case load of approximately 5000 avian patients each year placed a great demand on existing equipment and that hospital brooders were the single most vital element for the rapid recovery of critical and pediatric patients. We realized that even with an increased recovery rate of 10% or decreasing recovery time by 10% the overall impact on care provision would be significant. These figures take on even greater importance when estimated record reviews revealed average stock value of 200,000 and 300,000 dollars worth of client bird investment each year being placed with our care and that our clients' ability to remain profitable was heavily dependent on our performance. The brooders were calculated to pay for themselves within 3 to 6 months on a 10% improved patient recovery rate. The following observations and suggestions are presented for those clinicians considering designing their own brooders as a way of minimizing trial and error failure: 1. Keep it as simple as possible. A good design has few moving parts, smooth walls, and simplistic features but accomplishes a complex goal. Make all the auxiliary equipment easily detachable for cleaning purposes. 2. More expensive is not always better. High-quality parts, labor, and materials are never inexpensive, but a bit of diligent research and the liberal use of parts catalogues can make a great cost difference when building multiple units. 3. Use experienced consultants. The electrical control and brooders become very expensive when miscalculations force you to replace them. Use an experienced plastic shop with high-quality tools. They are not inexpensive. They can also give you good advice on the material's strength and limitations. 4. Learn about thermodynamics. This area is as foreign to most veterinarians as hydrodynamics when small concepts have major function implications. I had the pleasure of working with Mr. John Klea, an instrumentation engineer, and the project was more than a 2-year challenge. I have also discarded a complete set of brooders built with unsatisfYing results before using a consultant. 5. Pay strict attention to the heater placement. Keep the heater unit outside of the chamber to prevent excessive material wear due to heat. This also allows for quick detachment for disinfection purposes. Some materials are very intolerant of prolonged high temperatures and may become fire hazards or toxic fume producers. 6. Watch fan type and placement. Fans have some degree of vibration. Excessive vibration was found to be very stressful to most birds under constant exposure. We found computer cabinet fans with air bearings to have low vibration levels. Excessive wind force severely complicates brooder function. Air movement of such a level as not to noticeably blow a feather is ideal. It is very difficult to locate fans of lower than 32 CFM that have good construction. Ten to 12 CFM for 20 to 30 cubic feet of space is probably a good guideline whenever possible. Reduced air flow can be achieved by installing partial wind blocks, such as multiported plates with side vents, to exhaust excessive air flow away from the patient. 7. Solid-state temperature controls are necessary. Wafers, mechanical relays, and resistors are cheaper but not as reliable. Lightbulbs can be used as a heat

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source, too, but I do not believe a valuable hand-fed psittacine life should depend on it. Incandescent bulbs are designed as a light source and are a poor heat source. If economics require their use, two must be used because of the potential danger of one burning·out and the entire heat source being lost. 8. Temperature and humidity measurement is important. Purchase a quality, easily understood instrument that will give you a reasonably accurate reading of the environment in your brooder. Be sure it is removable and not accessible to the patient within. Remember "if you can't measure it, you don't understand it." 9. Pay attention to cleanability and serviceability. Is your design cleanable, or does it contain multiple areas for bacteria to collect? Is it serviceable, or does it require a college education to service it? Can a teenager pick it up easily without possibly being forced to drop it? 10. Evaluate your goals and your patients' needs. Medical brooders are as fundamental to avian practice as intravenous catheters are to canine/feline practice. Patient performance under crisis is directly linked to the quality of that product. With the value of :rvians rising, our ability to deliver higher quality medicine must be greater than ever before. With the ecologic pressures increasing to sustain many species, it makes sense to give ourselves the best chance of fighting the primary disease process presented to us instead of the iatrogenic ones we create. NUTRITION The subject of pediatric nutrition is as fundamental as it is controversial. Early infant daily growth rates should average in the 15% range, and nutritional intake should be balanced and maximized in its quality. No universally accepted standards exist for the nutritional requirements for all psittacine species during different phases of early life. A few studies have been pursued in smaller species such as the cockatiel, but cost factors involved in studying the larger species makes the establishment of standards unattainable at this time. The categories that should be evaluated before implementing a hand-feeding formula and schedule for the nursery include digestibility; bioavailability; percentages of total protein, carbohydrate, fats, fiber, and vitamin levels; hygiene; and cost. Some very general guidelines that have come to be accepted include protein levels of 18% to 20%, fat levels of 5% to 8%, an ability for the gruel mix to persist in a sustained suspension rather than solids settling out, and a lack of bacterial and fungal pathogens as delivered in the manufacturer's package. Because any hand-feeding diet should be extremely nutritious to sustain a consistent weight gain, it will also be highly supportive of bacterial and mycotic bloom. Formula should be protected during storage and always mixed fresh for each feeding to prevent the introduction of high concentrations of bacteria or fungi into immunoincompetent babies. Saving a few pennies on formula can lead to the loss of valuable offspring or the accumulation of veterinary bills and no definitive solution if this insidious source of reinfection is not investigated or appreciated. Water An often overlooked nutrient that plays a prime role in baby growth is water. Water is the single most vital nutrient consumed and the one most taken for granted. Water quality at the tap cannot be assured. Commercial water companies frequently purchase their water from multiple sources and may rotate or mix these sources on the basis of seasonal availability and a least cost formula. The system by which water is delivered can also have a profound influence on water quality. Pipe materials and seals, storage tanks, stagnation points in pipe design, and chemical additives can all lead to profound effects on growth and gut transit times. Water

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sources, especially natural wells or springs, should be checked for chemical toxins and biologic contaminants. Pseudomonas, Aeromonas, Escherichia coli and algae have all been documented. Ground water pollutants and heavy metals have been demonstrated in defective storage tanks and the use of older pipe materials. Lead pipes or pipes with significant numbers of lead alloy welds are still all too common. Flushing taps for 1 to 2 minutes before use, chlorinating systems regularly, and having in-depth laboratory analysis of your water supply is advisable. 5 • 6 A superior alternative is to use distilled or deionized water in the nursery to avoid entirely any risk of contamination. The various harmful agents may have speciesspecific sensitivity and age-related distribution. The greater the rate of gut absorption, especially evident in very young infants, the greater the expected long-term impact. Calcium

One of the more significant disease problems in pediatric medicine after frank stunting is metabolic bone disease. An intimate link exists between calcium, phosphorus, and vitamin D 3 . A proper dietary balance of calcium to phosphorus should be 1.5 to 2:1 along with the presence of vitamin D 3 to allow for normal skeletal development. Overall availability should also be evaluated because weak bones, especially legs, lead to a variety of deformities and pathologic fractures. Some species, especially African Greys, appear to have a greater need than other species. The cost of prevention is tiny in comparison to the cost of orthopedic bracing surgical correction. A special note should be made in reference to the overuse of vitamin D 3 because visceral gout has become a prominent pediatric and embryonal disease. The popular misconception of "more is better" has been amply demonstrated in the practice of vitamin supplementation and needless nursery mortality. Again, species specifically plays a great role in the clinical manifestation of this disease, as many species will not display signs of gout when fed the same formula as those succumbing to it. Macaws are by far the most sensitive, with conures being a second in comparison to less susceptible species such as Amazons. SANITATION It is proposed that most large psittacines do not gain immunocompetency until 4 to 6 months of age and are entirely dependent on yolk sac-derived maternal antibodies for protection. Sanitation is one of the fundamental keystones of successful pediatric medical management. Exposure to infectious debris is a guarantee for poor growth, constant morbidity, unacceptable mortality, and unnecessary budget expenditures. A disinfectant should be chosen for each area and item in the hatching room, brooder room, nursery, kitchen, and juvenile flights. An ideal type is germicidal and covers concerns for bacteria, fungus, Chlamydia, and viruses, including both enveloped (lipophilic) and nonenveloped (hydrophilic) types. 7 • 10· 17 Prevention should be a matter of routine. The questions of toxicity, causticity, cost, speed of kill, shelf life, and ease of use should also be evaluated in relation to each designated task. Different disinfectants are frequently chosen for floors, brooders, counters, and feed equipment. In general, quarternary ammonium compounds work well for floors, foot baths, and general hardware cleanup. Formalin has been used in egg hatcheries. Gluteraldehydes have great application for cleaning brooders, feed equipment, counters, kitchens, and cages. Oral and eye contact by either direct fluid or fumes should be avoided, even though Environmental Protection Agency tissue damage ratings are very low. This class of compounds is available in a variety of brand names in a multitude of specific preparation formulas, costs, and shelf lives. Chlorine bleach is the most cost-effective disinfectant available, but its use is

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limited by water hardness, dirt load, heat, sunlight, and short use expectancy. Tamed iodophors (i.e. Betadyne) are probably the least cost-effective but have excellent application. Chlorhexidines have excellent uses against fungus, most bacteria, and enveloped viruses. Nonenveloped virus, tuberculosis, and Pseudomonas control may not be adequate with this class. Check the specific label for guidelines. Strict protocol should be followed, and all utensils, brooders, and food preparation areas should be cleaned with each use. Water reservoirs used for humidity production should be drained and disinfected daily if possible. Food cups and especially water crocks are fertile breeding areas for bacteria. Other areas that have been identified as frequent offenders of recurring baby illness (chronic morbidity) include blenders, food processors, rubber "0" rings, refrigerator doors, cutting boards, feeding syringes, incubator water trays, food dispensing ladles, and, most importantly, human hands. Insist on scrupulous personal hygiene by all staff members as a matter of routine. UNABSORBED YOLK SAC Neonates may be presented within a few hours to days of hatching with partially unabsorbed yolk sac. The cause is generally attributed to incomplete growth or development before hatching. Incubator temperatures greater than optimal are most often determined to be responsible, as the chick hatches before the yolk can be entirely used, leaving some of the yolk sac protruding through the umbilicus. The greatest concern is that the yolk, which is a vital source of potent nutrients and rich in maternal antibodies passively received from the hen, is prone to punctures and tearing by either rough objects or sticking to brooder items such as shavings, diapers, or paper. Any tear quickly opens an avenue for potential infection (omphalophlebitis), with liver invasion following as well as immediate death due to hemorrhage. It is critical to address the immediate issues of nutrition, yolk sac protection, and disinfection of the affected sac via the following steps. 1. Fluid balance should be monitored and supported by the oral administration of Normasol or lactated Ringer's solution with 2.5% dextrose, proper brooder heat and humidity levels, and reduction of food solids by 15% until the sac has been entirely absorbed or 3 days, whichever is longer. 2. The area should be gently cleansed with an appropriate aqueous disinfectant · such as Nolvasan or Betadyne solution to remove caked-on debris or amniotic tissues without trauma or leaving any detergent residues. 3. The protruding sac should be lubricated and protected. This is most easily accomplished with a disinfectant/antibiotic ointment and a small nonstick wound dressing such as a l-inch section ofTelfa. The dressing can be changed as it becomes soiled or dried. Once the sac is fully absorbed, the dressing will neatly fall off of the umbilicus. 4. Use a padded cup for the chick within the brooder to avoid contact with any rough or sharp materials that may traumatize the sac.

FACIAL AND DIGITAL PUNCTURE WOUNDS These juvenile patients may present with a variety of signs, most notably hard, discrete, discolored, chronic nodules of the nonfeathered facial skin in macaws nearing the last periods of hand feeding. Other birds may present with defects in the beak or swellings and lameness of toes or feet. Biopsy reveals evidence of chronic inflammation or infection. This injury is due to bite wounds or claw

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punctures received during uncoordinated sibling movement or those sustained during feeding frenzy associated with the approach of the hand feeder. These wounds warrant some scrutiny because osteomyelitis is a common sequela where bony tissues are entered, as in beaks, wings, and toe regions. Radiographs are of great value both before and after treatment in assessing the actual status of the wounds. These lesions may not be readily apparent until weeks or months after the original injury, and therapy may need to be extended 1 to 2 months or more until all signs of osteomyelitis are vanquished.

GASTROINTESTINAL CONDITIONS Burned Crops A risk factor related to hand feeding infants is thermal trauma. Baby birds take food by reflex and swallow formula rapidly. Gruels should be fed in the 104° to 105° F temperature range. Feeding at less than 100° F usually results in poor acceptance, unless infants are specifically conditioned to receive this temperature early in life. Temperatures .of greater than 108° F contribute to the risk of thermal trauma to the crop. Crop burns are common, frequently affect multiple numbers of infants, and are entirely preventable using a high-quality thermometer, the cost of which is $15.00 or less. Surgical repair is often needed to prevent starvation, and closure should be accomplished in two layers, with the crop being sutured independently of the skin. Successful treatment is dependent on the extent of tissue loss after resolution of the original burn. Enough esophagus and ingluvies must remain so that food may pass unassisted. Even a very tightly closed esophagus can eventually be stretched to allow normal eating if soft foods are given in small amounts. A crop tube may be used for the initial days or weeks following surgery. Antibiotics are routinely recommended to prevent the common bacterial opportunists, and anti-inflammatory drugs may be of great value in acute conditions. After the areas of food temperature, sanitation, nutritional quality, and handfeeding techniques have been addressed, certain alimentary tract problems present themselves as one of the most common entering complaints in a pediatric practice. Sour Crop. This condition is diagnosed with some regularity and is merely a descriptive term for the rancid odor derived from food sitting in the ingluvies. The causative agent may be bacteria, yeast, or improper food items. This term is also overused by laypersons to describe insufficient gut peristalsis, which results in delayed crop emptying. An investigation into the site and the specific agent responsible for this condition should include wet mounts, cytology, cultures, and possibly radiographs and barium series. A majority of cases involve stomach or intestinal pathology originating from diverse sources such as yeasts, bacteria, viruses, improper formula temperatures, physical obstruction (i.e., grit impaction), secondary ileus, and dehydration. It is vital to remember the agent identified is usually a symptom of the true cause, which may stem from improper sanitation practices, violation of closed flock protocol, inappropriate diet, and so on. Vomition. This is a general sign and results when inflammation or physical or physiologic obstruction is present. Nausea can also be responsible and is seen associated with car sickness, otitis interna, encephalitis, and certain medicinal use (i.e., doxycycline or trimethoprim sulfate suspension in lovebirds and baby macaws). The same diagnostic efforts as used for crop stasis apply here. However, the prognostic significance is substantially greater than that for simple regurgitation, which is merely a physiologic sign associated with overfeeding or excessive pressure on the filled crop (i.e., hand pressure during restraint). The cause of vomition should be vigorously pursued if it continues for more than 4 to 8 hours. Diagnostics

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should include the following, as an unresolved case of an infant being unable to accept and process nutrition runs a relatively greater risk of entering the point of no return when compared with an adult bird. These are listed in order of greatest to least level of concern: 1. 2. 3. 4. 5. 6. 7.

Cytology of crop and fecal material. Cultures of mouth, crop, and feces for bacteria and fungi. Gram stain of mouth, crop, and feces. Blood panel. Urinalysis. Radiographs with or without barium series. Exploratory surgery.

Therapeutic efforts are summarized in Table 2.

Diarrhea. This rriay be pathologic or physiologic, and items such as water content of the diet, salt intake, food type, and medications in use should be examined. Disease causes include infectious viral or bacterial enteritis, parasites (especially protozoa, such as Giardia), cold or heat stress, secondary opportunists such as Candida, malnutrition, dehydration, and toxicity, including previous pharmaceutical use. This is usually, but not always, less difficult to correct than decreased peristalsis. All treatments must be modified based on clinical observation and diagnostics. It is critical to distinguish between ingluveitis, proventriculitis, enteritis, inflammation, obstruction, physiologic disturbances, and infectious disease before committing to a long-term protocol. The most common error is not to look deeper than what is visible to the naked eye or to the touch. "Sour crop" is as inappropriate a diagnosis as is "the squirts." The presence of Candida on a crop swab does not preclude the possibility of Pseudomonas. Fecal passage does not dismiss the possibility of a string enteritis. Be certain of your patient and its immediate needs. Differential diagnosis should include (most to least common): 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13.

Malnutrition. Dehydration. Thermal stress (environmental). Inappropriate/irregular feed schedule. Bacterial/mycotic disease. Parasitic disease. Thermal trauma to gastrointestinal tract. Sepsis. Generalized inflammation with loss of lumen patency. Viral disease. Foreign body. Intussception. Torsion/volvulus.

These signs may occur alone or in combination or as a result of each other. Monitor the patient's signs. Red, dry, angry skin with flakiness is due to dehydration and is the rule rather than the exception. Bluish babies are often cold with slow-moving intestines. Babies that do not immediately drop into deep slumber within a few minutes of feeding, but continue to move, cry, flap, or exhibit frantic behavior are indicating ongoing discomfort whether it is due to pain, hunger, cold, heat, or some other source. Be sure to double-check thermometers, hygrometers, food temperature, and fecal passage, even if this means using a new instrument to double-check the current one.

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Table 2. Therapeutic Efforts Heat Active support controlled to ideal levels: l-2 days of age 2-5 days of age Newborns Early down feathers Early pin feathers to juvenile

98° F 96° F 92-94° F 9~92° F 86--88° F

Rehydration IV, oral routes; subcutaneous route: 2%% dextrose in Normasol is considered optimal, and oral route is considered only slightly less affective than IV. Subcutaneous absorption may be impaired if the peripheral vascular network has been compromised by dehydration, shock, chill, or toxicity. It is imperative to regulate brooder relative humidity to prevent iatrogenic dehydration Improve gut peristalsis Reglan, 5 mg/kg twice a day subcutaneously or intramuscularly Gastrointestinal tract protectant Sucralfate (Carafate): Tablets crushed and mixed with dextrose as suspension Small animal dose, 50 mg/kg PO twice a day Antimycotics Nystatin, 100,000 IU/300 gPO birth weight twice a day Ketoconazole, 30 mg/kg PO twice a day Gentian violet, oral or vent wash, feed additive poultry dose Antibiotics Oral aminoglycosides for gut lumen pathogens should be limited to twice a day use for 3 days only to avoid gut sterilization Oral suspensions: trimethoprim sulfate, chloramphenicol, and ciprofloxacin are good general broad-spectrum choices. Chloramphenicol may be less desirable owing to its bacteriostatic action Parenteral antibiotics: piperacillin, cefotaxime, cefotur, enrofloxacin, and netromycin all are excellent first-line selections Final selection of bacterial therapeutics should be designated by culture sensitivity results Analgesics Flunixine (Banamine), l mg/kg once a day for 3 days maximum Butorphanol (Torbutrol), l mL/20 lb twice a day; significant reduction of patient mortality and recovery time have been noted Vitamin supplementation Vitamin A, E, B, C, and K use may not only be beneficial but mandatory in cases in which malnutrition or specific disease etiologies are involved. Be particularly cautious of potential bleed out in those babies with coagulation deficiencies (i.e., polyomavirus or vitamin K deficiencies), as intramuscular administration may lead to a crisis. Subcutaneous route may be advisable when questions arise as well as for general use when frequent injections are anticipated for an infant patient to avoid the additional stress of severe myositis with a reduced skeletal muscle mass of the diseased infant/ juvenile Diet manipulation Reduce fat and protein feed levels to increase rate of digestion/crop empty. Be cautious not to endanger the patient with malnutrition Increase level of short-chain carbohydrates-available as human pediatric supplement or in sport electrolyte mixes (i.e., Eclipse) for ready metabolism Elemental amino acid solutions (AA Solution) or electrolyte/amino acid solutions (FreAmine, Abbott Laboratories Abbott Park, IL) Table continued on following page

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Table 2. Therapeutic Efforts (Continued). Decrease gruel viscosity with pancreatic enzymes (Prozyme, Pancreazyme) added to food before meal. Be certain to predigest formula after being mixed to normal consistency, as decreased viscosity can delude hand feeder into believing that more concentrate is needed, leading to the serious risk of creating a hyperosmotic gruel. Be cautious not to aggravate the existing problem Crop support Soft, resilient cloth material such as stockinette, T-shirt cloth, Vetwrap, or infant tube sock tops may all be used to support and lift crops to assist in their emptying. Gentle continuous pressure should be applied so that the crop and its contents are held dorsal to the thoracic inlet, where food emptying may be maximally assisted by passive gravity flow. Insufficient tension allows flaccid or pendulous crops to assume a position below the inlet without the "crop bra" and prevent normal food drainage, whereas excessive bra tension leads to regurgitation. Soiled crop bras must be changed frequently. Rapid growth rates must also be attended to, as decreased wing clearance necessitates a refitting every few days. The crop bra may be slipped over the torso with wing slits or tied as a bib above and below the wings

GIZZARD IMPACTION The introduction of small rocks or gravel particles enhances the grinding action of the ventriculus in the natural habitat. The amount of grit or gravel present is very small because the holding capacity of the gizzard of a large goose or turkey is only approximately a tablespoon or less. Therefore, fowl and ground birds such as wild Galliformes rarely stop to pick up new grit. It is common to have new clients ask about the types and quantities of grit that are necessary for keeping their pet psittacine healthy. It is important to point out to pet bird owners that despite the fact that wild birds and fowl ingest grit routinely, it is an unnecessary item for caged birds and in many circumstances highly undesirable. Much controversy surrounds these statements because of the persistence of a traditional practice and the lack of contact that the average bird owner has with the medical complications that can arise when grit is misused or abused by birds or their owners. The foods that should be offered on a proper dietary program are sufficiently soft enough to be easily ground and digested by the ventriculus. Vegetables, fruits, grains, dairy products, cooked eggs, and lean cooked meats are all excellent supplements for the traditional seed mixes. These five food groups require no more grit than they would in human digestion. Since grit is not needed, obviously no type is the best. However, there are a myriad of choices that range from a variety of gravel mixes in assorted particle sizes and colors to oyster shell or limestone granules. These may come in the natural colors or be colored green or blue. Some of these colored additives may incorporate some additional vitamins or minerals. These latter two categories are technically not grit but are really two forms of calcium carbonate. They are readily absorbed by the body after exposure to the low pH of the stomach acid and do not persist as solids in the gizzard. A question of potential toxicity has been raised in regards to oyster shell in recent years. Oysters are farmed and harvested on the shallow continental shelves off the coast. These shallow waters have become heavily polluted over several decades when they lie near dense human populations due to industrial and urban runoff. Since oysters and other mollusks incorporate minerals to form their shells, it is possible for the pollutants to become trapped within the mineral layers as they are laid down. Some loads of oyster shell, particularly the black or dark gray variety,

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have been incriminated as having high levels of lead, among other heavy metals. The question is often posed by clients as to how much grit does a bird need. Again, none is probably the best response. It is important that bird owners understand the physiologic processing of grit by avian systems. The actual amount of grit used in wild avian gizzards is very tiny. The volume of a budgie's or a cockatiel's ventriculus is V4 to Vz mL. Since grit is an enhancer to the processing of the food that fills this second stomach, the amount of grit that can properly accompany it is very small indeed. It is also well documented that grit remains in the ventriculus for long periods of time. Birds that are explored surgically or examined at necropsy even 6 months after having grit removed from their diet will still have grit persisting there. The actual amount of grit that is actively used by a budgie is just enough to cover a small fingernail three to four times each year. Several specific conditions are of great concern for pet birds, however. The first involves the ingestion of grit as a mineral substitute. Birds fed the traditional diet of only dried seeds without access to the important food groups such as fruits, vegetables, dairy products, and meats or eggs can develop serious malnutrition. This is all too common, and these birds may be driven to consume anything available to satisfy the "mineral craving" associated with certain forms of malnutrition. This is classically seen in Third World children who are observed to eat mineral-laden dirt when surviving on a nutritionally deficient diet. These birds do not stop eating excessive amounts of grit until the original problem is corrected. The second condition involves a less understood phenomenon in which the presence of stomach or intestinal diseases, such as infections or diarrheas, leads the affected bird to gorge itself on volumes of grit for reasons not yet understood. These unfortunate birds are then confronted with two serious problems, one of which is the original disease process and the second one being the physical obstruction that occurs. The only solutions are either through surgical removal or the use of repeated flushings through a gastric tube. Neither option is highly desirable in the affected patient. The final concern with grit ingestion on a free choice basis is that pet birds demonstrate a high level of curiosity in exploring their environments, especially juveniles. The consumption of inordinately large volumes of grit, walnut shell, and so on may be the result of environmental exploration, curiosity, or boredom. The same is seen with puppies and kenneled dogs. Taste appreciation or enjoyment does not appear to be a motivating factor. A certain incidence of pica is seen in some pediatric cases, especially those hand-fed birds that are not given the degree of attention they desire or are demonstrating other signs of social stress, neglect, or similar maladaption. Plastic toys and wood and metal objects may be ingested and discovered by the clinician in addition to grit as part of this psychosis and is most often observed in young hand-fed cockatoos. Increased awareness of gizzard and proventricular particle matter impaction has been brought to light through the greater use of radiologic examination of those patients that present with gastrointestinal signs of anorexia, malaise, vomition, melena, or hematorrhea. Many times the possibility of stomach impaction is dismissed on initial history and examination owing to no impending shock, known ingestion of particle matter, and a chronic duration of several days to months. Xray studies and upper gastrointestinal barium series are of great value in determining the status of gastric patency. It is suspected that avian species do not react with the same signs or schedule of clinical manifestations as are seen in mammals. Birds that present with these conditions appear to be relatively undisturbed by the internal events ongoing in comparison to small mammal patients. Tolerance of conditions that would be fatal in cats and dogs appears to be endured until the final stages of the process are reached.

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I have witnessed approximately 30 gizzard impactions over the past year in psittacine patients. The only alternative that appears to have any degree of success in relieving this fatal condition is a controlled gastric lavage using a soft French rubber catheter with open tip and saline. The traditional approach of ventriculotomy is described in the literature as being a relatively routine procedure for this diagnosis. My experience and that of my colleagues is that the patients are often far progressed with particulate impaction and the mortality during or immediately after surgery is approximately 80%. I believe this alarmingly high rate of failure is due to the advanced state of compromise and associated systemic toxicity coupled with the inferior support systems devised for avian surgical patients at this writing in comparison to the bird that has recently swallowed a single foreign object that requires retrieval. I would encourage those veterinarians attempting to relieve gastric impactions to consider the use of a recently developed technique for gastric lavage as an initial attempt to avoid surgery in an expedient manner, as follows: The patient is masked and tracheally intubated with a snug fit to avoid fluid inhalation. The patient' is placed in dorsal recumbency and the head placed below the thoracic inlet. A relatively firm fitting French rubber catheter that has been cut to allow maximum discharge diameter for fluid flow and particle recovery is introduced down the esophagus and guided into the proximal proventriculus by blind guidance. Care must be taken to prevent excessive expansion of the thoracic esophagus and pressure on the vagal nerve during passage by relatively oversized tubes. Once the tube is situated within the proventriculus, contact with the foreign bodies may be felt by contact resonance with some experience. A catheter tip syringe filled with warmed saline previously attached and flushed through the catheter before entry is then gently used in an alternating flush and retrieval action to dislodge delicately and recover the tightly compressed particles. Great care must be taken to avoid overfilling the proventriculus and possibly rupturing weakened walls or forcing any significant volumes of fluid into the oropharynx. The syringe may need to be emptied frequently to dispose of accumulated rock, walnut shell, and so on to prevent reintroduction on subsequent flushes. Be sure to note any appearance of blood in the fluid or attached to particles. Any significant amounts of blood may indicate excessive trauma to the proventriculus or esophagus by the tube or foreign bodies trapped alongside of it. Some hemorrhage is nearly always unavoidable. The foreign bodies are saved and evaluated for recovered volume every few flushes to determine if sufficient amounts have been removed. Comparison of the recovered volume and that seen in the x-ray films allows the surgeon to determine if enough has been removed. Remember that the x-ray film is demonstrating a three-dimensional volume and may be difficult to compare directly with that in the recovery container. By the same note, substantial volumes may occupy the proventriculus alone. I have removed over 15 mL of gravel from a Buffon's proventriculus before recovering the material trapped in the gizzard that was actually responsible for the clinical condition. It is neither easy nor necessarily desirable to recover 100% of the material because a limited number of gizzard particles are not considered pathologic. The surgeon should attempt to advance the tube down to and it is hoped, into the gizzard at some point to recover the more significant particles from the ventriculus where the reduced organ volume may tend to resist recovery as easily as from the proventriculus. It is common to note a through-and-through enema effect with the presence of saline at the vent during the procedure. This procedure may not be curative, but does offer an excellent alternative to surgery for those patients not able to withstand the stress of abdominal surgery, thereby allowing for additional time to support and evaluate the patient for future surgery. It must be stated in clear terms that at least some to severe trauma may be sustained by the patient during this procedure and the use of gastric lavage is

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reserved for those patients that warrant its use. Sufficient success with this procedure over ventriculotomy during the past 2 years justifies its use as a viable option. In all cases, the use of rigid instrumentation from the oral cavity to the gizzard should be avoided because of the relative lack of resistance that the thoracic esophagus and proventriculus offer to stainless steel. Iatrogenic puncture of the upper gastrointestinal tract is often not felt by the surgeon. In those patients with long cervical spines, such as large-breed macaws and cockatoos, it is extremely beneficial to initiate the procedure with a ingluveotomy to reduce the distance necessary to reach the gizzard impaction site. In these cases, it is important to hold the crop in place with stay sutures and to pack off the crop with absorbent sponges to prevent backwelling into the oral cavity. Check around the tube frequently to look for dislodged particles that should be removed manually. Needless to say, this condition is as underappreciated as it is underdiagnosed. Unfortunately,,neither of these two deficiencies can be corrected in sufficient time once a patient is presented with this all too common problem, and, therefore, the process of upper gastrointestinal barium examination, gastric lavage, and ventriculotomy must be pursued as needed to save these critical pediatric cases. Perhaps the greater lesson is in prevention, and it is recommended to evaluate stringently clients' choices of substrates in the brooder, weaning box, and fledging areas. Toys should be selected carefully, and access to inviting types offoreign bodies, such as rubber objects, plastics, styrofoam, foam rubber, walnut shell, aquarium gravel, grit, corncob litter, and tinsel, should be eliminated. PANCREATITIS This condition has been associated with two different causes. The first category is viral, and the two leading agents are herpesvirus (Pacheco's virus) and adenoviruses, which are poorly understood in their scope and importance at this time in regard to psittacine pediatrics. The second category is more similar to that of classic small animal internal medicine and involves the spontaneous reaction to high lipid dietary intake. The patients are often those that have been pushed by hand-feeding programs promoting growth for size. It is not uncommon to find evidence of heavy use of heavy fat concentrate supplements in the diet regimen, such as Nutrical or STAT. Clients often report very mild degrees of lethargy and gasping several days before death. Histopathology reveals evidence of acute, necrotizing pancreatitis with severe edema and little functional tissue being present. LEG CONDITIONS Leg deformities arise owing to a wide scope of origins. These range from dietary factors (calcium deficiency), genetic defects, congenital defects (slipped tendon), poor surface choices (linoleum or shallow nest box shavings), and parental trauma, to developmental malpositioning in the egg. 1· 5 • 9 • 14• 20· 22 · 23 Some of these conditions may be simply corrected by changing the bedding or diet and require no active corrective devices. 5 · 22 Many of these patients require physical therapy in the form of manipulation, splints, or surgery. Many of even the most serious axial deformities can be corrected through braces and splinting soon after hatching up through a few weeks of age. Additional age and size development require more vigorous orthopedic restraint and longer correction periods. Some conditions have no known cure at this writing. However, as a general rule, the younger the age that correction is initiated, the less severe and prolonged the

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therapy that is usually required. Tiny infants may not be amenable because of their size or fragility for many procedures. Calcium and yitamin deficient diets should be corrected. Leg damage may or may not require additional therapy. Radiographs are often helpful in identifying what future problems may be expected. Valgus (lateral deviation) and varus (medial deviation) of the hips, knees, hocks, and metatarsal are also evident and the degree of correction appropriate for the deformity can be determined. Mild leg deformities of the hips, femur, or tibiotarsal bones can be treated using deep retaining cups padded with tissue paper or absorbent toweling, which allow the leg growth to be directed in a vertical fashion. Toweling must be changed frequently, and care must be taken to restrain infants passively agailpt self-trauma. Leg hobbles fashioned from masking tape, cloth, and bandages may be fastened between the metatarsal bones, hocks, or tarsometatarsal regions. Avoid taping hobbles directly to the legs because the rapid growth rate will rapidly lead to vascular impediment. ,Again, a deep cup should be used to prevent babies from laying face down and causing excessive stress on the coxofemoral joints, which will lead to more severe growth deformities later that are not correctable if not recognized in time. More severe leg defects require fixed braces or casts to encourage a redirection of bone growth. Plastic bowls and cups may be cut down so that a base and two side bars remain. The legs are heavily padded with cast padding or cotton. The padded leg is then lightly wrapped in roll gauze. The leg is next strapped or taped to the upright plastic bar for support. It is important to use a restraint device that has a comfortable natural distance between the legs so that new deformities are not created in the femurs. It is also important to avoid any pressure points on the legs, as pressure necrosis will occur in a few hours in the infant's delicate tissues. Support must be given to the chest and abdomen as well to prevent pressure points at the tops of the leg wraps. Lack of ventral support of the chest allows for food to be regurgitated as the baby's head is lowered in an attempt to balance itself. Foam rubber pads work well and may be stacked to the appropriate height to prevent the baby from sagging down into the leg wraps. The duration of application varies, but 5 to 15 days is generally sufficient for most cases. Alternative arrangements include the use of aluminum rod stands, which form a halo over the baby's thighs and pelvis and extend in front and behind to provide a stable base. The baby is strapped to the frame in the same fashion as for the plastic leg stands. This set-up is especially suited for large psittacine babies such as macaws. A second alternative is to open cross cuts into sheets or blocks of foam rubber and to insert the feet and legs of the patient through them. The depth of the form brace is dictated by level and severity of the defect. The cross cuts should be wide enough to allow for good vascular flow and several days of growth. In all cases, attention should be paid to the position of the feet. Marked deviation from the anterior toe position requires the feet being taped back into a normal position. The toes must be checked at least once daily because the lack of space under the tape created by skeletal enlargement will cause rapid necrosis. The most severe deformities may require surgical intervention during or after the rapid growth phase. Several options exist under different circumstances. Healed leg fractures, especially folding fractures, may be rebroken under an anesthesia that provides good muscular relaxation (i.e., isoflurane). The newly fractured and reduced leg should be fixed in a softly padded cast or splint for healing. More chronic or solidly healed fractures may require invasive surgery to reduce irregular bone architecture. Wedge osteotomies can be accomplished with highspeed drills, diamond enamel dental disks, and metal hobby cutting wheels (Dremel). Great care must be taken to avoid causing soft tissue damage, especially

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to the vessels and nerves in the local region. At times it is necessary to dissect out the affected bony lesion bluntly so that the cutting tools can operate without risk of soft tissue trauma. Most psittacine legs are amenable to this procedure even if the alignment is not completely perfect because most patients' leg strength is sufficient to compensate for any lack of alignment later on. The bones should be set using intramedullary or Kirschner pins in combination with Robert Jones casts, fixed splint stands, or Kirschner-Ehmer apparatus. Healing is rapid under good conditions and is often complete in as few as 12 to 14 days. Watch for pressure sores when leg size outgrows casts and splints. Knee Trauma Correction One of the most frustrating leg conditions to correct in avian patients is the repair of luxated knees, secondary to loss of cruciate or collateral ligaments. Traditional attempts to provide for joint stability through wraps, splints, and casting have all met with abject failure. A technique recently developed in our clinic appears to have tremendous potential on a low-risk, low-cost basis. Essentially the joint is held in rigid fixation through the use of a K-E apparatus employing very thin K wires or, in the case of very small patients such as young cockatiels or lovebirds, small gauge hypodermic needles (23 to 27 gauge). The procedure was developed in a response to breeders and pet owners in possession of valuable species in whom life without pain and normal ambulation was not possible relying on all prior techniques and whose diminutive size prevented the use of conventional small animal cruciate repair protocols. This technique had been previously used in mature raptors in which functional leg use was mandatory for re-release into the wild following luxation of the knee. The pins are placed through the diaphysis of the femur and the tibiotarsal bones in an anteroposterior direction, perpendicular to the axis of the leg and parallel to each other. At least two pins are placed proximally and distally to the. knee joint; however, three pins in each bone are desirable. The architecture of the leg and the abundant skin around the femur frequently prevent more than two pins from being placed in the femur. It is also difficult to establish pins that are perfectly parallel when performing the procedure in a closed manner as is recommended. Generally a finger grip and careful progress allow for a near midline shaft positioning of the pins. The femoral pins should be placed first, as the pins of the tibiotarsus inhibit good hand access if they are placed ahead of them. Once the pins are established, the K wires are cut to a length that allows for adequate bracket installment but prevents any excess length from catching on cage furniture. The leg is then positioned into a slightly flexed position of a natural stance before applying the bars. K-E bars may be formed using dental acrylics, hoof acrylic, or other epoxy-like materials. It is much preferable to use a nonexothermic material to prevent the risk of thermal trauma to bony tissues, but cold water gauze wraps have been used on setting hoof acrylic with success. Be cautious not to leave rough edges or excessive volumes of synthetic bar material that may lacerate skin or cause pressure necrosis. Some pressure necrosis may be unavoidable because the leg is not in a completely natural position during the surgical position, and the weight of the viscera may cause increased abdominal contact in an upright position. Any significant increase in body mass following additional body growth may alter the relative degree of contact as well. Applying a small amount of ointment to the bar apparatus or covering it with padding may be indicated. Substantial bruising may occur in the postoperative period and anti-inflammatories such as flunixin are used before surgery. Severe musculoskeletal discomfort is usually noted for 3 to 5 days postoperatively but soon diminishes with good weight bearing and ambulation thereafter. I would highly recommend resisting the temptation to use a medial to lateral

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approach, even though the initial surgical procedure is physically more convenient for the surgeon, as· the pins cannot be placed at a distance as proximal in the femur as when an anteroposterior position is used. Also, stability and patient comfort may both be substantially reduced in heavier birds if a lateral approach is used. The recommended healing time is 30 to 40 days in juveniles to adults for large species (i.e., macaws and cockatoos) at this time and approximately 21 days in small species (cockatiels and rosellas). Pin removal is in the classic style using sterile procedures. Again, marked patient discomfort is noted for 3 to 5 days after this segment of the care protocol and the use of flunixine (Banamine) is once again recommended to promote weight bearing and recovery. The procedure appears to have mixed tolerance in regard to acceptance by untamed aviary birds, but some can be temporarily tranquilized until acceptance occurs. The majority of birds, both pets and breeders, can be allowed to resume perching and caged activities within 5 days or so following the repair procedure but should be frequently observed and prevented from jumping from heights over 6 to 8 inches at first.

CONSTRICTED TOE SYNDROME This phenomenon is not yet understood in its etiology but has been commonly recognized for decades as a pediatric and juvenile condition with a species predominance in macaws, African Greys (especially congas), Eclectus, and to a lesser extent, cockatoos. The physical appearance involves a rapid and progressive swelling of the distal portion of the toes, especially the outer digits. The rear digits appear to be more frequently affected than the anterior ones, although not to an overwhelming extent. The initial phases of damage include a rapid swelling of the affected toe, occasionally with fluid-filled vesicles being visible on the dorsal aspects. A constrictive band of fibrous tissue quickly forms at the anterior aspect of the damaged area and becomes increasingly deeper. Subsequently the toe experiences an avascular crisis and resolution flows over the ensuing weeks as the tissues desiccate and shrink. The final stage involves the loss of the affected areas at the point of construction with a pink area of scar tissue over the shortened digit bone. The original cause is suspected to be one of several causes or a combination thereof. Excessively dry brooder environments appear to be associated with a high incidence of this problem. It is theorized that any puncture or laceration in the digits of these babies allows for leakage of fluid at an abnormally high rate due to the adverse affect that low-humidity environments has on rain forest species not adapted to such conditions. The body may then attempt to minimize the damage process by laying down fibrosis at the level of the original injury site. As the fibrin matures and as a result of the physical characteristics of the cylindrical toe tissues, the formation of a constrictive toe band may be inevitable. It is interesting to note several observations, such as that the rear toes bear a relatively greater percentage of weight than the forward toes, that the outer toes are likewise more used, that most babies are raised under less than optimal humidity conditions, that desert climates report a higher incidence than coastal and tropical climatic regions, and that a similar restrictive band type lesion is reported in the small intestine of large psittacines (another circular organ). The statistical prevalence of the species reported may be due to their body size and weight or possibly a result of statistical prejudice due to their popularity and monetary value as potential pet stock sales. A second suggestion is a similar condition reported in the journal of Pediatric Medicine by the American Medical Association termed amniotic band syndrome,

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wherein children from birth to 12 years old were affected by a constrictive band of fibrous ti~sue involving an appendage. The cause is a remnant of the amnion, and the condition is treated by plastic surgery to relieve and reposition the tissue band present. Successful treatment is primarily dependent on early intervention, whether it is through surgical incision and pressure wraps, massage, dimethyl sulfoxide soaks, or warm soaks, and is usually futile once the tissues of the distal toe are debilitated. All of these efforts have proved successful in the early stages of the acute portion of the disease process. I do not believe that surgical incision of the band is always necessary as long as the condition is watched for and treated immediately by more conservative means. Later efforts often require the opposite approach. Prevention requires an evaluation of the aviculturist's management program and nursery protocol. Brooder humidity, sanitation, brooder substrate quality, and baby hydratiop should all be closely reviewed for prevention. I prefer using low volume, forced air brooders with either adequate humidity production or nursery room humidifiers in addition to bar towels (terry cloth) or reusable diapers to provide an absorbent foot base without overdrying to bottoms of baby feet. Clients who have changed to this more appropriate environment report almost universal disappearance of this perplexing phenomenon. Be aware that this is not a fatal disease but does represent a substantial source of financial loss to the breeder as well as being an indicator of management problems within the production unit.

NECK DEFORMITIES Improper head positioning is seen secondarily to an inability to hold the head up due to weak musculature or congenital defects in the cervical spine. The relatively large head size of infants makes these conditions somewhat frequent, and the head may be twisted to one side or held inverted on the shoulder or back. Some of these babies demonstrate defects from birth, which may be the result of egg malpositioning, but the assumption that genetic defects are involved should be delayed until proof is available. 14• 20 • 23 Other infants do not begin to express neck defects until after several weeks of age, and the reasons for the differences in onset remain unclear. Therapy consists of early and direct correction. As in other bony tissue defects, early correction provides for rapid and low-tech recovery due to the very rapid growth rate, which lends itself to the passive encouragement of bone remodeling. Some babies can be cured by regular physical therapy by having the neck turned to the forward position for 10 to 15 minutes, four or five times daily. Others require more constant reinforcement, especially when the head is unable to be lifted voluntarily. In these cases, the use of soft collars and neck braces has been unsuccessful because of the resulting pressures on the crop that prevent adequate food intake. To achieve enough rigidity with a neck brace, the crop cannot be filled. An excellent and simple technique is to use a plastic container with square or slightly rounded corners. The infant's head is taped into the corner with padding under the chin and contact areas to prevent pressure sores while the body remains unencumbered. The container should be deep enough to allow the baby to rest comfortably in a vertical position with absorbent bedding underneath. The weight of the body passively stretches the cervical region so that natural growth allows for a return to the normal position and equilateral muscle development without impingement on the crop. The baby is only untaped for feeding and cleaning until the correction is complete. It may be beneficial to employ hypoallergenic tape for those babies with sensitive skin.

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BEAK DEFORMITIES The two categories seen in pediatrics include acquired and congenital. Nearly all of the beak defects acquired in the nursery or nest are trauma related, especially as a result of bites or nail punctures by parents, siblings, or large species of infants. Congenital defects include improper beak formation, developmental defects due to vitamin deficiency/toxicity, improper temperature during incubation, or toxicity from biologic (Aspergillus) or chemical sources. The trauma cases may be repaired with surgical materials such as methylmethacrylate glues (Vet Bond or Nexaband), dental acrylics, or stainless steel mesh. Care must be taken not to entrap infectious material or damage the germinal layers of the cere or the vascular layer below the keratin. A loss of premaxillary bone also prevents a regeneration of the vascular layer overlying it and its accompanying keratin coat. This has been well demonstrated by the inability to regenerate the upper beak when it is avulsed by a parent or cage bully. Replacement by prosthesis is also difficult at best with the technology currently available for cases of complete beak avulsion. The two predominant congenital beak defects seen in infants are mandibular prognathism and scissors beak. Both may be corrected through the application of prosthetic devices. Scissors beak may be corrected using a general anesthetic and grinding the overgrown mandibular beak at an angle that forces the upper beak back to the midline. A ramp consisting of stainless steel mesh material coated with epoxy or cyanomethacrylate adhesive is built lateral to the upper beak on the affected side. The base is wired to the lower jaw with stainless steel wire, and the framework is coated with dental acrylic for a smooth, graduated prosthesis that forces the upper beak into a normal position when the beak is closed. Correction times are shorter when the baby is younger and require 5 days to 4 weeks. Cockatoos and macaws are the most commonly affected species, but any species may be affected. Mandibular prognathism involves the inability of the upper beak to clear the lower beak and thus the tip grows down into the mouth, with tongue damage frequently resulting. The incapacity of the bird to self-feed properly renders it a permanent patient, unless corrected through prosthetic devices. Correction involves encasing the upper beak in a dental cement prosthesis after reshaping it so that the upper beak is forced up and out over the lower beak. This stretches the joint of the upper beak, and eventually the beak occludes naturally with new beak growth. Once the upper beak has reached beyond the lower beak, the correction is permanent and the prosthesis can be removed. The duration of the prosthesis application varies with age but generally averages 2 to 4 weeks in infants. I would highly recommend reviewing the Association of Avian Veterinarians Annual Conference Proceedings for 1989 through 1991 for a more extensive coverage of these protocols.

LACK OF PROPER EYE APERTURE FORMATION This is seen with the greatest frequency in cockatiels and may vary in its severity from a total lack of separation of the lids (cryptophthalmos) to a slight narrowing of the normal lid separation (ankyloblepharon). 3 The most significant aspect of this congenital defect is that it is resistant to therapy; the proposed etiology is that it is due to the lack of formation of palpebral muscle formation, thereby preventing the palpebrae from retracting in a normal fashion. Therapy has been attempted using ophthalmic ointments, surgical separation, electrocautery, corticosteroids, retention sutures, and chemical cautery (silver

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nitrate). No successful therapy has been discovered as of this writing, and the end results of those tried to date. are either a recurrence of the original condition or a complete los£ of the lids, leading to an eventual loss of the orb through desiccation. It is recommended that all patients be evaluated for their ability to function ~s is. Those with limited vision should be allowed to adapt to their handicap and those few who do not adapt as a result of a lack of vision may be recommended for euthanasia. It is not recommended to breed the parents again until further evidence defines what genetic involvement may exist. FLEDGING TRAUMA Several injuries are presented to clinicians during the fledging period or shortly thereafter due to hard impact landings as a result of weak pectorals, incompletely feathered wings, severely trimmed wings soon after fledging, or inappropriate trimming of retraces. The injuries may be minor and easily diagnosed such as strains, sprained legs, bruised wing tips, or concussions. Other injuries are unfortunately misdiagnosed and furthermore are not addressed in their prevention as a result of the lack of understanding by owners. In particular, the three injuries seen repeatedly in the same clutch are split chests, tail avulsion, and central nervous system trauma. Split Chests This injury is seen in very young birds that are making their first attempts to fly or are inherently heavy bodied and require additional wing strength to sustain uplift on their short wing spreads. In particular, cockatiels, African Greys, and large-sized Amazon Parrot babies are most commonly involved. These lesions may be fresh and actively hemorrhaging or chronic and heavily crusted before discovery by the owner. Many times the original injury may be compounded by multiple reinjury to the same area. Treatment consists of evaluating the extent of the injury, stemming any active hemorrhage, debriding old crusts, and closing the wound surgically. Chronic injuries that have been repeatedly retraumatized may require efforts to clean the area and close it. I recommend subcuticular closure patterns whenever possible to avoid selfinduced dehiscence at home. Nexaband or an equivalent surgical adhesive may be used in small wounds. It is imperative that dismissal instructions include cage rest, movement restricted to hand-controlled out-of-cage visits, and sufficient time to allow tissue healing as well as improved flight strength to avoid a second occurrence. Any patient sustaining injuries due to excessive wing clipping or trimming of the tail should have some or all of the affected flight feathers pulled to allow for replacement of these vital tissues. Tail Avulsion These patients are presented as a result of weak or short wings not being able to sustain flight, and the resulting tail landing leads to the tail being forcibly ripped back and off of the pygostyle. The resulting injury has the appearance of a darkringed oval defect posterior to the vent with a protruding red mass most often misdiagnosed as a "prolapse." The exposed tissue is in fact the coccygeal muscles controlling the tail movements and covering the pygostyle. The injury may be hours or weeks old. Treatment consists of cleaning and debriding any necrotic tissue in preparation for closure of the wound. The defect may be closed with any strong nonabsorbable suture after flushing the exposed tissues. It is recommended to infuse the exposed tissues with an antibiotic before closure to prevent secondary infection.

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Once again, it is vital that these patients be kept under strict confinement or hand control until such a time as their flight muscles strengthen or new primary feathers regrow to sustain loft, or a repeat of this condition is likely. Central Nervous Syndrome These patients are depressed and lethargic or may be very bright and alert while simultaneously being paretic or paralytic in both legs. The diagnosis of central nervous system trauma may be concluded based on a combination of case signalment and physical examination. The important signs to evaluate include the presence of subcutaneous hemorrhage over eyes, ceres, or cranium and non-weight bearing legs. Lack .of pupillary light response is not necessarily, in fact rarely, associated with this disease. The patient's prognosis is dependent on the presence or absence of deep pedal pain reflex. A positive response to intense toe pinching places the patient in the 95% category for return of full function. A lack of positive reflex reaction to deep pedal pain within 72 h~urs places the patient in a grave prognostic category. The status of cloacal tone and use is also helpful in not only establishing the patient's status, but also its progress. It may be necessary to assist the patient manually to void urinary and intestinal waste products to avoid sustaining a toxic condition. Treatment is typical in the use of anti-inflammatories at doses based on the initial presenting signs as well as artificial alimentation, fluid therapy, vitamins, and vent expression as needed. Therapy may need to be continued for several days to weeks in more severe cases and is encouraged as long as the lack of deep pedal reflex persists. Owners may be taught to care for invalid patients who demonstrate vigor and self-feeding when prolonged care is indicated, especially when voiding of the cloaca must be assisted.

OTITIS EXTERNA This rarely addressed issue occurs with some rarity, but is significant on its detection in the individual patient. The condition is usually detected in its early stages by the aviculturist during hand feeding or by the veterinarian during the purchase examination. More chronic cases are generally brought to the attention of the owner by the constant wetness of one ear area or by the associated sour odor that may accompany it. The statistical incidence of otitis externa has not been reported and is assumed to be low, probably owing to the anatomically open nature of the external auditory canal of avians. Diagnosis involves physical examination, scoping of the affected ear (most usually under sedation or brief gas anesthesia), cytology, and culture for yeasts and bacterial agents. Common organisms seen in these cases include Candida and gram-negative bacteria, especially E. coli and Pseudomonas. Treatment consists of standard antiinfectives, but may require prolonged use in some cases. Reculture is recommended in all cases.

PEDIATRIC AIDS Table 3 lists the items routinely used for pediatric cases and dispensed to aviculturists for the care of babies at home in the nursery. Many can be purchased over-the-counter by owners. 1• ._9 • 21

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Table 3. Pediatric Aids ENVIRONMENTAL

Thermometers Hygrometer Sponges Diapers/bar towels Chlorhexadines Tamed iodophors Gluteraldehydes Quarternary ammoniums Bleach Formaldehyde and potassium permangenate crystals

USE

Incubators, nursery, brooders, formula preparation Brooder/incubator humidity Humidity production for brooders Excellent brooder substrate Brooder/incubator humidity, cups, nursery disinfection around infants Hand scrub, food bowls Nursery/brooder disinfectant, baby scales, kitchen equipment, feeding equipment, foot pans Floors, tables, foot pans Assorted use away from birds, especially in kitchen and food preparation areas Incubator disinfection

NUTRITIONAL SUPPORT

Lactated Ringers solution with 2'12% dextrose Pedialyte (has 2V2% dextrose) Eclipse Digestive enzyme powder Amino acid solution

Lactobacillus acidophilus powder Stat Corn syrup (white) Rice cereal flakes Neocalglucagon syrup D-Ca-Fos Powder Catheter tip syringes Crop bra material French rubber catheter (large gauge) Stainless steel gauge needles MATERIAL SUPPLIES

Tissue glue Telfa pads Culturettes Iodine solution Iodine ointment Nystatin suspension Gentamicin or amikacin oral solution Chloramphenicol/trimethoprim sulfa, ciprofloxacin Flunixine (Banamine) Metochlopramide (Reglan) Butorphanol (Torbutrol)

USE

Rehydration formula Commercial children's rehydration formula Short-chain carbohydrate source Predigestion aid for gut stasis patients Purified protein source requiring no digestive effort Assists in disease recovery if fed routinely as part of formula High fat/carbohydrate concentrate Sterile sugar source for energy supplementation Easily digested source of carbohydrates Calcium-vitamin D 3 supplementation Calcium-vitamin D 3 supplementation Feed delivery For pendulous crop support Crop suction and food delivery Feeding compromised or wild patients, crop vacuuming USE

Wound sealant Protects unabsorbed yolk sac Sample collection before drug use Navel swabbing Coating retained yolk sacs Anti-yeast therapy Upper gut antibiotic, nonabsorbed First-line antibiotic (after swabs are taken) Anti-inflammatory/analgesic Gut stasis therapy Analgesia

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SUMMARY These few subjects are only a small fragment of the scope of pediatric medicine but are critical in their impact. The depth of material needed to cover the subject adequately should fill a textbook. If, however, aviculturists could master these seven areas, the numbers of babies requiring medical or surgical therapy would decrease dramatically. The entire purpose of preventive medical management is actually the elimination of medicine as it is practiced today. That goal, as desirable as it is, is quite some time off, and education remains the key to improving the quality of the lives and future of our patients. Attention to detail and the comprehension of normal physiology of these nondomestic (and generally tropical zone origin) birds will lead to great inroads in understanding the true underlying cause of pediatric problems; improved patient recovery rates; and a better appreciation of the nebulous but critical relationships among potential pathogens, infection, disease, perforinance, and productivity. Given our truly limited technical position, the veterinarian who learns to use the environment for the patient's health is light years ahead of what you can purchase for the purpose of actively forcing the direction of a complex situation. REFERENCES l. Abramson J: Macaw husbandry. AFA Watchbird Cites Issues, 1989, pp 19-21 2. Burton J, Frazer B: Animal Microbiology, vol II. Blackwell Scientific, Cambridge, MA, 1977 3. Buyukmihci NC, Murphy CJ, Paul-Murphy J, eta!: Eyelid malformation in four cockatiels. JAm Vet Med Assoc 196:1490-1492, 1990 4. Clipsham R: A look at the future of aviculture and avian medical management. AF A Watchbird 15:50-54, 1988 5. Clipsham R: Introduction to avicultural medicine. In Proceedings of Association of Avian Veterinarians, 1989, pp 223-238 6. Clipsham R: Preventive aviary medical management. In Proceedings American Federation of Aviculture Veterinary Seminar, 1989, pp 15-28 7. Clipsham R: Preventive health care for aviculture: Disinfection and sanitation. AFA Watchbird 15:16--22, 1988 8. Clipsham R, Thompson DR: Avicultural management consultation for the distant aviculturist, part II. AFA Watchbird, 16:12-14, 1989 9. Ellis J, Goodek H: Husbandry and management of electus roratus. AFA Watchbird 12:43, 1986 10. Gaskin JM: Considerations in the diagnosis and control of psittacine viral infections. In Proceedings of Association of Avian Veterinarians, Oahu, Hawaii, 1987, pp 1-14 11. Harrison GJ, Harrison LR (eds): Clinical Avian Medicine and Surgery. Philadelphia, WB Saunders, 1986 12. Hoffman K: Tool use by aviculturists: The artificial incubator. AFA Watchbird 13:16-21, 1987 13. Hofstad MS, Calnek BW, Reid WM, et a!: Diseases of Poultry, ed 8. Ames, Iowa State University Press, 1984, pp 1-37 14. Jordan R: Parrott Incubation Procedures. Ontario, Silvio Mattachione and Co, 1989 15. Joyner KL: Psittacine pediatric diagnostics. In Avian/Exotic Animal Medicine Symposium, School of Veterinary Medicine, University of California, Davis, 1990, pp 22-45 16. Klea JA: In Proceedings of the Avian Pediatric Seminar, Concord, California, 1990, pp 79-88 17. Kowalski, Mailman: Is your disinfection practice effective? JAm Anim Hosp Assoc 1973 18. Marshall T: Aviculture and the theory of co-evaluation. AFA Watchbird 17:52-53, 1990 19. Mohanty S, Dutta S: Veterinary Virology. Philadelphia, Lea & Febiger, 1981 20. Olson GH: Problems associated with incubation and hatching. In Proceedings Association of Avian Veterinarians, 1989, pp 262-267 21. Petrak ML: Diseases of Cage and Aviary Birds. Philadelphia, Lea & Febiger, 1982

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22. Ring L: Aviary design and management. In Proceedings Association of Avian Veterinarians 1989, pp 250-257 23. Takeshita K: Relationship of egg position during storage and incubation on early embryonic growth and hatching of broiler eggs. Thesis, Master of Science, Auburn University, Auburn, AL, 1980, pp 1-72

Address reprint requests to Robert Clipsham, DVM California Exotics Clinic 5734 East Los Angeles Avenue Simi Valley, CA 93063