Infectious Diseases of New-World Camelids (NWC)

Llama Medicine

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Infectious Diseases of New-World Camel ids (NWC) Thomas R. Thedford, DVM* and LaRue W. Johnson, DVM, PhDt

Within the new-world camelids (NWC) we have four species, two of which are deemed to be wild (exotic), the guanaco and the vicuna; and the domestic counterparts of these two, the llama and the alpaca, respectively. For the sake of consideration of infectious diseases, of course, all four species would be considered equally susceptible to the diseases mentioned. Furthermore, because NWC are closely related anatomically and physiologically to the old-world camelids, which include the dromedary and bactrian camel, we may have liberty to extrapolate from their infectious disease susceptibility. It would seem appropriate to preface a study of infectious diseases of the NWC with the fact that, in the United States, these animals appear to be basically healthy, especially in regard to infectious diseases. Most health afflictions as we observe them in providing routine veterinary service, fortunately, are management- or environmentrelated. Further demonstrating their relative uniqueness in regard to infectious diseases, there are numerous examples of experimental infection in NWC, yet the same diseases rarely are observed clinically in natural settings. This latter aspect, however, does raise some questions about carrier status.

DISEASES OF CAMELS THAT MAY AFFECT NEW-WORLD CAMELIDS In a series of articles, "The Camel in Health and Disease," edited by Higgins,27 the following infectious disease conditions were reported as occurring in the dromedary camel. These are listed not as evidence *Extension Veterinarian, Food and Fiber Animals, Oklahoma State University, Stillwater, Oklahoma tAssociate Professor, Food Animal Medicine, Colorado State University, Fort Collins, Colorado

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of occurrence in NWC but as possible differential diagnoses, simply because of the similarities of the species. Viral Diseases

Camel Pox. Camel pox is a disease commonly seen in the Middle East and Indian subcontinent. It usually affects young animals and is very similar to contagious ecthyma seen in other small ruminants. The disease is caused by a parapoxvirus. Signs include lymphadenopathy and brown crusty lesions around the mouth, mammary glands, genitals, inguinal, and perianal region, which usually heal in about 3 weeks. Treatment was reported as symptomatic. Rabies. Signs are similar to all other species and only rarely have been reported in camels. Rinderpest. Reported to affect all cloven-hoofed animals but has not been observed in camels even when in close contact with cattle with the disease. Serological evidence also is sketchy. Experimentally, a reaction was seen when live virus was inoculated into camels, but clinical signs were nonexistent. Foot-and-Mouth Disease. Camels react experimentally to infection with the virus, but it is unlikely that they develop clinical signs. They may be involved with transmission of the virus as an asymptomatic carrier, however. lBR, BVD, Parainfluenza 3. Serological evidence indicates infection, but no clinical signs have been reported. Rift Valley Fever (RVF). Camels exhibit illness, mortality, and abortions when infected with this virus. They are suspected of being involved in the transmission ofRVF virus from central Africa northward into Egypt in 1977. Bacterial Diseases

Anthrax. Three forms of this disease occur naturally in camels. They vary in severity, from a protracted form exhibited as superficial swelling of the lymph glands or a diarrhea; to an acute form with fever, trembling, labored breathing, and swelling of the throat, neck, and groin; to the peracute form characterized by sudden death. Brucellosis. It appears that camels may be infected by several of the species of Brucella organisms. They tend to harbor the type common in the area; that is, if they are in contact with cattle, B. abortus is fairly common. On the other hand, if goats are the most common contact animal, B. melitensis infection occurs. Abortion is fairly common; however, attempts at isolating the organism from milk have met with variable success. Tuberculosis. Under most husbandry conditions, camels seem to be relatively resistant to tuberculosis. When housed with cattle, however, an incidence of about 3 per cent was .seen in the Middle East. Lesions usually are seen as discrete miliary lesions of the lungs. Lesions also are seen in the spleen, kidneys, and trachea. The organism is found in the milk. Tuberculosis was considered more of a problem in camels in the United States when they were housed under classical zoological park management.

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Salmonella. This organism causes enteritis, septicemia, and abortion in camels. It appears as an important disease of young animals and has been transmitted to humans through consumption of contaminated meat. Pasteurellosis. Pasteurella multocida causes a hemorrhagic septicemia-like disease in camels and also may cause abortion. Paratuberculosis (Johne's Disease). Most evidence is serological, with only one clinical case reported, that being a zoo camel in the United States. Signs reported were similar but more severe than those in cattle. Leptospirosis. Only serological evidence exists to suggest this disease affects camels. Clostridial Diseases. The only diseases reported are tetanus and enterotoxemia typ~s C and D. Klebsiella spp. and E. coli have been reported as causes of acute mastitis. Brucella and Streptococcus spp. have been reported as causes of abortion, and Proteus, Serratia, Enterobacter, Klebsiella, E. coli, Enterococci, Bacillus, Corynebacterium spp., Staphylococcus aureus, and Streptococcus pyogenes have been isolated from cases of metritis. Corynebacterium pseudotuberculosis also has been isolated from cases of caseous lymphadenitis. Serological evidence also suggests that Listeria monocytogenes and Chlamydia may cause disease, but clinical evidence is elusive. Cutaneous Fungal Infection. Ringworm in camels most commonly has been found to be caused by Trichophyton spp., but Microsporum occasionally is isolated. REPORTED DISEASES IN LLAMAS AND ALPACAS Of more specific value are those diseases that have been reported as occurring in llamas and alpacas. Much of the information from South America concerns alpacas and has been reported in journals published there. A relatively recent translation of the book by Escobar l l lists a very significant bibliography; the most comprehensive coverage of infectious diseases, however, appears to be the series of articles by Moro.28 Bacterial Diseases Disease in general is relatively rare in the South American camelid. The following diseases have been reported at one time or another by veterinarians. Most experience, however, indicates that management, parasites, reproductive problems, and heat stress are of much more importance than infectious diseases, in general, and bacterial diseases, specifically. Anthrax. A report exists of infection in very young llamas that had been given a calf's dose of the Stern strain of vaccine. 8 Signs included severe depression, inability to stand, tachypnea, and pale mucous membranes. There was no hemorrhagic discharge from the body, nor could bacteremia be detected. At death, the blood clotted

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and the spleens contracted. Because slightly older young llamas had no reaction to the vaccine, it was postulated that an overdose had been given to the younger, lighter-weight llamas, with an elaborated toxin from replication of the spore-like vaccine accounting for observed clinical signs. Naturally occurring cases of anthrax have been observed in alpacas; never at over 2000 meters of elevation, however. 28 Clostridium Peifringens Types C, D, and A. Infection by this organism has been reported several times28.4o.42.43 and has been widely discussed in meetings across the United States. Type C most commonly is seen as sudden death in the nursing cria. Three cases of type C sudden death of nursing crias have been observed by the Colorado State University Veterinary Teaching Hospital (CSU-VTH). Two of the cases involved failure of passive transfer of colostral antibodies, while in the other case the dam had not been immunized. It is prevented best by vaccination of the dam, monitoring colostrum intake, and then immunizing the young llama no later than at 4 to 6 weeks of age. On premises with a history of type C occurrence, routine administration of type C antitoxin is encouraged. Vaccination for enterotoxemia most commonly is done in combination with tetanus and malignant edema. Type A Clostridium perfringens has been reported in Peru, but has not been diagnosed in North American to date. There is no vaccine available for type A enterotoxemia. Exterotoxemia types A and C will be characterized at necropsy by hemorrhagic loops of bowel and hemorrhagic gastritis, particularly of the distal portion of the third compartment. Two cases of type D enterotoxemia in mature llamas have been diagnosed at the CSU-VTH. Typical necropsy lesions were observed to be characterized by pulmonary congestion, petechial and ecchymotic hemorrhage of the lower neck and axillary space musculature, and a pericardial effusion containing a fibrinous clot. Some veterinarians are using eight-way clostridium vaccine available for sheep. It is inexpensive and should be safe. The other clostridial diseases are not common problems, but with the high value of the animals, the vaccine certainly is worthwhile. One case of malignant edema complicating a snake bite caused the death of a Colorado llama. Brucellosis. Brucella melitensis has been reported to affect alpacas where they have been in association with sheep in South America. 2.29 The likelihood of infection in the United States probably is very low, in that the rate of infection of B. abortus currently is very low and, as a general rule, llamas and alpacas are not kept with cattle. Many states require a negative brucellosis test for entry, nonetheless. To date we are unaware of any positive Brucella tests from North American camelids, including a significant number of samples taken from llamas that have aborted. Tuberculosis. Very few cases of tuberculosis have been diagnosed in llamas in the United States. 47 The likelihood of this disease occurring is relatively remote and the species appears to be relatively resistant, but testing is required by several states as an entry requirement. The caudal fold test is used, even though the most sensitive area

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for testing is unknown. Current research suggests another site to be more effective for the intradermal t~st and that an enzyme-linked immunosorbent assay may be very applicable. 48 Research and clinical observations in South American literature confirm South American camelid susceptibility to the various strains (M. tuberculosis, M. bovis, M. avium, and M. microti) of Mycobacterium. 5 ,9,30 Cases have been reported worldwide, especially in ZOOS.23,36 Unreliable testing continues to cause frustrations, however. A case of M. avium infection in an aged llama was diagnosed at the CSU-VTH during a necropsy following its untimely death by a malicious shooting. No other animals in the herd were detected as reactors in a subsequent routine caudal fold tuberculin test. Another Colorado llama was detected as a reactor during routine interstate shipment testing procedures. Follow-up comparison cervical tests deemed the animal positive. The animal was destroyed and at necropsy no gross lesions were detected. In addition, no proof of the tuberculosis diagnosis could be demonstrated following extensive histopathological and culture efforts. Leptospirosis. Although the potential for clinical manifestations by Leptospira spp. in the NWC is every bit as great as in most other species, reports have been rare to date. Serological evidence of infection in alpacas would indicate approximately a 3 per cent incidence. 24 Classical signs of hemolytic anemia were observed in a 3-month-old guanaco that died. Following a complete necropsy and histopathology, it was concluded that this baby died of leptospirosis. 19 While investigating a herd problem of abortion in Oregon, significant rising titers were demonstrated in a number of the dams involved. The problem apparently was contained by subsequent vaccination of the reproductive herd. 21 Alpaca Fever. A bacterial septicemia occurring in South America caused by Streptococcus zooepidemicus causes a rapidly fatal condition of NWC.6,28 Stress often is the predisposing factor to onset, with transport, shearing, and processing for any reason potential stressors. Clinically, the disease is characterized by elevated body temperatures (greater than 104 OF), anorexia, weight loss, ascites, and relatively rapid death. This condition has not been proven to occur in the United States; however, descriptions of some gross necropsies have been consistent with the disease. It would appear that high-dose penicillin (10,000 U twice daily) is the therapy of choice. Prevention can be facilitated by minimizing stressful situations; no absolute control measures have been found in South America, however. Johne's Disease. Suspected cases of Johne's disease caused by Mycobacterium paratuberculosis have been reported in both the United States and United Kingdom. 1,4 As with other species, the difficulty in making a definitive diagnosis is discouraging. At the CSU-VTH we have investigated two clinically suggestive cases extensively, but neither was confirmed. One did demonstrate colonic granulomatous enteritis; no acid-fast organisms were detected however. Chronic weight loss and loose feces in otherwise apparently healthy camelids should be considered as clinical Johne's disease suspects. Lumpy Jaw. In their native South America, the NWC seem to

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develop a high incidence of osteomyelitis caused by Actinomyces spp. 3,10 The principal route of infection, no doubt, is from contaminated feedstuffs penetrating the oral mucosa. Early detection is imperative to afford a cure through drainage, as well as sodium iodide and penicillin therapy. The incidence of this problem in the United States appears to be quite low. We have, in addition, observed intermandibular swellings caused by Actinobacillus lignieresii. Tetanus. It appears that the incidence of clinical tetanus in the NWC is relatively low in the United States, given that only one confirmed case has been reported (Fowler ME, personal communication, 1988). Cases are described with greater frequency in South America, however.28,49 Clinical signs to be observed are similar to those in other domestic species, with a history of surgery or a wound generally revealed. Because of the value of NWC in the United States, incorporation of a sound tetanus vaccination schedule into a herd health program is to be recommended. Colibacillosis. Fortunately, the incidence of neonatal diarrhea caused by E. coli is very low. Neonatal diarrhea is a relatively rare complaint, with nutritional factors being the more common explanation. Efforts have been made in South America to characterize enteropathogenic E. coli.41 Listeriosis. Reports that llamas are susceptible to infection by Listeria monocytogenes gives some cause for concern. 13,26,28,46 Although current feeding practices usually do not have llamas eating spoiled forages (especially corn silage), the potential exists for llamas to consume infected feeds. Clinical signs referable to the central nervous system apparently are identical to other affected species-namely, a head tilt and tendency toward circling. Mastitis. Incidence of clinical mastitis in the NWC appears to be relatively rare; however, systemic illness and loss of one or more of the four-quartered mammary glands is described by colleagues (Fowler ME, personal communication, 1988).20 One might speculate that the vast majority of cases go undetected, based on the relatively high incidence of hard quarters indicative of chronic mastitis. To date, we are unaware of any reports dealing with the routine use of the California Mastitis Test (CMT); one might speculate it to be of value, however, especially in attending the dam and offspring that do not appear to be doing well just after birthing. Diagnosis and treatment generally will follow the same principles as for other species; however, intramammary infusion should be approached with caution because the multiple orifices (two to four per teat) are small and could be damaged easily. Culture and sensitivity results likely will dictate the most effective parenteral therapy. Mastitis caused by E. coli strains have proven to be the most significant, with many cases being characterized by severe toxemia in the dam, often proving to be fatal (Fowler ME, personal communication, 1988). Although local therapy of hot packiilg and massage are indicated, most llama dams are not very cooperative. Pinkeye. It appears that the overall incidence of keratoconjunctivitis (pinkeye) in llamas is low, and the vast majority of cases would

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appear to have a foreign body (dust, plant material) as the basic root of origin. Reports of truly infectious pinkeye are rare; in one such case, however, the isolated organisms were found to be Staphylococcus aureus and Moraxella liquefacians. 7 On two occasions, we have observed multiple animal pinkeye, but the predisposing factor of dust following a wind storm was believed to be the primary cause. Local medication with nonsteroidal triple antibiotic ointments, along with parenteral tetracycline (LA-200) at 9 mg per lb body weight generally has proven effective, providing any foreign body has been removed. Dennatophilosis. The opportunist Dermatophilus congolensis has produced severe cases of wool rot in llamas in those parts of the country where conditions are right and incidence occurs in other domestic species. Heavy wool cover over the back in high moisture climates predisposes llamas to this complaint. Lesions of moist crusting, particularly over the dorsum of the back, are highly suggestive, but confirmation generally is made by impression smears of Giemsa-stained scabs to demonstrate the large chained organisms. Treatment is facilitated by local attention to lesions, reduction of wool covering, and systemic penicillin. Protection from prolonged exposure to moist conditions will help reduce incidence. Foot Rot. Although the padded foot of the llama is impressively resistant to infection, if subjected to predisposing moist conditions for prolonged periods of time, it appears to be invaded by numerous organisms, including Bacteroides fragilis, Fusobacterium necrophorum, and Actinomyces spp. Local debridement and bandaging with an astringent powder (Domeboro, Myles, Inc., West Haven, CT) have proven very beneficial. A specially designed boot also has helped, along with systemic penicillin (20,000 U per lb body weight once daily). Abscesses. Facial swellings often eventuate into localized abscesses, which usually are full of liquid pus, but on occasion are caseated. It would appear that most have their origin from oral foreign body penetration, variably involve teeth, and if left alone usually will produce an inviting location for subsequent surgical lancing, drainage, and packing for 24 hours with 7 per cent iodine-soaked gauze. Organisms isolated (Streptococcus equi, Corynebacterium spp., and Actinomyces pyogenes) generally are regarded as penicillin-sensitive, making parenteral therapy choices easy. Sanitation in the feeding area is to be scrutinized, as well as attention given to excessive quantities of sharp plant material (foxtails/cheat grass) in the available forage. Necrotic Stomatitis. Oral injuries have been observed to be complicated with infection by Fusobacterium necrophorum. Oral surgery or known oral injuries likely should be accompanied by systemic penicillin therapy. Salmonellosis. Although there is no reason to suspect that the NWC shouldn't be susceptible to Salmonella infections, we are unaware of any primary cases presented with clinical signs of explosive watery diarrhea and variable amounts of hemorrhage. Unfortunately, it is the case that in many university teaching hospitals, postsurgicalf stress salmonella cases do occur in the various large animal species,

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especially the horse. In spite of significant numbers of surgical and stressed llama cases that apparently have gone through the various veterinary hospitals around the country, however, we are unaware of salmonella cases resulting. Furthermore, in spite of significant numbers of papers originating in South America, no specific mention is made of salmonella cases. Based on the apparent lack of reports to the contrary, we can assume that the NWC are relatively resistant to salmonellosis. Fungal Diseases

Ringworm. The overall incidence of dermatomycosis in North America appears low, but the NWC are susceptible to dermatophytes of the Trichophyton and Microsporum genera. In our experience, T. verrucosum has been the most common isolate reported, with lesions closely resembling those that we characteristically associate with cattle. Transmission of llama dermatophytes to other species, including humans, is to be given serious consideration. Treatment generally is facilitated by sunlight, but is accelerated by removal of organic debris followed by topical application of 7 per cent iodine or captan (1 oz per gal) on a biweekly basis. Coccidioidomycosis (Valley Fever). New-world camelids living in the endemic areas of the southwestern United States are reported to be highly susceptible to "Valley Fever." A wide variety of clinical presentations are possible, depending on organs affected, and include respiratory signs, neurological manifestions, or possibly only a dermatological presentation. 15,35 The causative organism, Coccidioides immitis, is a soil saprophyte found in arid desert regions of the southwestern United States, Mexico, and several South American countries, including Venezuela, Paraguay, Argentina, and Bolivia. Inhalation of arthrospores is the most common route of infection. Although this is considered an infectious disease, it is not contagious from one animal to another or from infected animals to humans. Serologic testing will indicate exposure, but only animals showing clinical signs along with seroconversion should be regarded as having the disease. Necropsy of affected individuals, of course, will vary with organs affected, but gross lesions will appear similar to the granulomas of mycobacterium, while the histopathologic lesion is characterized by pyogranulomas with numerous spherules characteristic of the yeast-like fungal infection that is present. The disseminated form that seems to be most common in NWC may have virtually every organ in the body involved with singular granulomas, or several may coalesce into large irregularly shaped masses. The dermal form no doubt could serve as a differential diagnosis for several skin presentations, including dermatophilosis, ringworm, and zinc-responsive dermatosis. Classical dermal coccidioidomycosis will be characterized by nodular lesions 1 to 3 cm in diameter or by extensive raised plaques. Distribution of lesions has been variable, with the perineum, face, and limbs being the most common sites. Considering the nationwide movement of NWC, as well as impor-

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tation, coccidioidomycosis must be a considered diagnosis for any chronically ill animal, especially if the clinical presentation includes signs referable to the respiratory or nervous systems. There appears to be no successful treatment recommendation at this time. CryptococcoSiS 14 and aspergillosis (Smith J, personal communication, 1988)37 have been reported to occur in llamas. As with many species, animals having chronic disease involving prolonged antibiotic therapy and immunosuppressive courses of steroids unfortunately are prone to developing infections of these fungal or yeast agents. Feeding spoiled forages (hay and especially silage) definitely would increase the possibility of infection. Viral Diseases

Foot-and-Mouth Disease. As with the old-world camelid, this disease has been reported as an experimentally induced disease, and the species are relatively resistant to infection by the virus. Llamas and alpacas more likely are involved in transmission of the virus rather than a severe clinical disease presentation. 12,22,25,34 Contagious Ecthyma. This has been reported as a clinical disease in llamas and alpacas (Thompson T, personal communication, 1986).18,33,38,39 Signs and severity are similar to that seen in other small ruminants, with potential for transmission within the species. Public health concerns apply to "sore mouth" infections of NWC. Rabies. As in all other mammals, this disease may occur when the animal is bitten by an infected animal. 16,31 Signs would be similar to those seen in other species. In some areas where incidence of rabies is high, some veterinarians are recommending use of the killed vaccine in llamas and alpacas. Equine Herpes 1. As reported by Rebhun and coworkers,44 alpacas and llamas were housed in an exotic animal farm when they became infected. Signs included blindness and neurologic signs, from nystagmus to head tilt to paralysis. Other clinical signs were dilated, nonresponsive pupils; elevated body temperature; and various neurological signs; with permanent ocular damage. A virus indistinguishable from equine herpesvirus I was isolated from the affected animals. All affected animals were euthanized. Subsequent to this case, only a few sporadic reports have been made of acquired blindness associated with elevated serological titers to equine herpesvirus I (Graham D, personal communication, 1987). The actual impact of these observations in the NWC in North America remains to be fully appreciated. Although there is a vaccine used in the equine population to protect against this infection, the indications and efficacy of available vaccines for the NWC remain unknown. If vaccines are to be used in the face of theoretical high risk, the product surely must be a killed-virus type repeated often to attain immunity. Blue Tongue. In contrast to sheep, where clinical disease is important and quite apparent, blue tongue infection in the NWC would appear to behave fllore like that observed in cattle, being predominantly asymptomatic but creating a significant serological titer. Be-

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cause the serological titer suggests the possibility of the animal being a carrier of the orbivirus, many states and foreign countries permit only blue tongue seronegative individuals to qualify for entrance. Reduction of seropositive individuals no doubt will be achieved by minimizing exposure to the Culicoides spp. vector. Reduction of breeding grounds for the vector, as well as use of insecticides or repellants, will have a positive impact on the problem. Other Viral Agents. Experimental disease has been produced using vesicular stomatitis virus, but naturally occurring cases are not described. 17,28 An outbreak of vesicular stomatitis in teaching animals at the CSU-VTH caused severe lesions in cattle; however, two llamas cohabitating the same corral and using the same feeding and watering facilities failed to develop clinical signs and did not seroconvert. Neonatal diarrhea fortunately has been a low-incidence problem in NWC. Although it would be deemed a likely possibility that a rotavirus could contribute to the clinical picture, no reports of isolation are evident in the literature. Neonatal diarrhea causing mortality in llamas has been presumed to be caused by a coronavirus, based on histopathological microscopic lesions (Patterson K: Personal communication, 1988). From alpaca serological surveys conducted in Peru, it appears that rotavirus seroconversion does occur; however, no information pertaining to coronavirus was presented. 45 Antibodies to parainfluenza 3, bovine respiratory syncytial virus, bovine herpes I, border disease virus, and influenza A virus were detected in the same study; no clinical disease has been reported, however. Of further interest is the fact that no serological evidence of ovine progressive pneumonia or bovine leukemia virus was detected in the same study. This serological information would not necessarily prove or disprove susceptibility of NWC to these various agents; however, it may provide an explanation when positive serologies are detected. Chlamydiosis is discussed in the article on reproduction. SUMMARY

Although there are notable infectious conditions that are capable of producing clinical disease in the NWC, overall, these species are quite healthy. Of the bacterial diseases, enterotoxemia caused by Clostridium perfringens types C and D would be deemed the most significant in North America, while type A also would be regarded as important in South America. Other important bacterial infections of potential concern are tuberculosis, Johne's disease, anthrax, malignant edema, actinomycosis, tetanus, and the South American condition referred to as alpaca fever, which, to date, has not been observed in North America. Fungal infections include classical ringworm, principally caused by Trichophyton spp., and the cases of coccidioidomycosis that are associated with the arid desert lands of the southwestern United States.

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Most notable of naturally occurring viral infections in the NWC would be rabies, ecthyma, and a recently described blindness neuropathy that has been associated with the equine herpesvirus I. NWC can be infected experimentally with agents causing hoof-and-mouth disease and vesicular stomatitis, but naturally occurring cases do not seem to occur. Serological evidence of exposure to many viral agents, including blue tongue, parainfluenza 3, bovine respiratory syncytial virus, bovine herpesvirus I, bovine viral diarrhea, influenza A, and rotavirus, has been demonstrated; however, no clinical disease associated with these agents, as yet, is apparent.

REFERENCES 1. Appleby EC, Head KW: A case of suspected Johne's disease in a llama. J Comp Pathol 64:52-53, 1954 2. Acosta M, Ludena H, Barreto H, et al: Brucellosis in alpacas. Rev Inv Pec, IVITA Univ Nac San Marcos, Lima, Peru 1(1):37 -49, 1972 3. Aguilar MF: Necrosis de las mandibulas en alpacas. Ganaderia (Lima) 4(0):77 -79, 1952 4. Anonymous: Johne's disease suspected in a llama. J Am Vet Med Assoc 128:354, 1956 5. Barsallo J, Samame H, Castagnino D, et al: Tuberculosis in animals from Mycobacterium tuberculosis. Res VI Cong Nac Ciencias Vet, Piura, Peru, 1980, p 76 6. Bautista D: Enfermedad 0 fiebre de las alpacas; nota preliminar sobre las investigaciones realizadas en el Departamento de Puno. Lanares y Lanas. 6(25}:6-7, 1955 7. Brightman AH, McLaughlin SA, Brumley V: Keratoconjunctivitis in a llama (Staphylococcus aureus, Moraxella lique/acians). VM/SAC 76(12):1776-1777, 1981 8. Cartwright ME, McChesney AE, Jones RL: Vaccination-related anthrax in three llamas. J Am Vet Med Assoc 191(6):715-716, 1987 9. Castagnino D, Singer N, Hernandez J: Experimental tuberculosis in alpacas. Tercer Bol Ext IVITA, Univ Nac San Marcos, Lima, Peru, 1968, pp 75-77 10. Cuba CA: Osteomielitis del maxilar in alpacas. UNMSM Facultad de Medicina Vet Revista 4(1-4),1949 11. Escobar RC: Animal breeding and production of American camelids. Talleres Gra..ficos d Abril Editores and Impressores. Av General Vivanco 739, Pueblo Libre, Lima, Peru, 1984, pp 304-320 12. Espinoza AM: A serological and biochemical study of new field isolates of foot-andmouth disease virus type A in Peru, 1975-1981. Vet MicrobioI8:555-562, 1983 13. Fernandez Baca S: Alpaca raising in the high Andes. Wild Anim Rev 14:1-8, 1975 14. Fowler ME: Llama medicine and surgery. In Proceedings of the 60th Western Veterinarian Conference, 1987, pp 334-342 15. Fowler ME: Medicine and surgery of South American camelids. Ames, lA, The Iowa State University Press, 1989, in press 16. Franco E: Brote de rabia en alpacas de una hacienda de Departmento de Puno, Peru (IVITA), Boletin Extraordinario 3:59-60, 1968 17. Gomez D: Tests on the sensitivity of camelids to vesicular stomatitis. Anales Ii Cong Nac Med Vet y Zoot, Lima, Peru, 1964, pp 403-406 18. Hartung J: Contagious ecthyma of sheep: Cases in man, dog, alpaca, and camel. Lippengrand des schafes. Tierarzthche Praxis 8(4):435-438, 1980 19. Hodgin C, Schillhorn van Veen TW, Fayer R, et al: Leptospirosis and coccidial infection in a guanaco. J Am Vet Med Assoc 185(11}:1442-1444, 1984 20. Kress pJ, Torrey S: Mastitis in llamas: Diagnosis, treatment, prevention. Llama World 1(3}:21, 1983 21. Long P: In Fowler ME (ed): Llama Medicine Workshop Proceedings, 1984, pp 65-66 22. Lubroth J, Yedloutschnig RJ: Foot-and-mouth disease studies in the llama (Llama

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(LaRue W. Johnson, DVM) Colorado State University Veterinary Teaching Hospital College of Veterinary Medicine and Biomedical Sciences 300 W. Drake Road Fort Collins, CO 80523