- Email: [email protected]
Proximal renal tubular dysfunction
A D V A N C E S
forcement are less stressful and potentially better for the welfare of dogs.
TRAINING METHODS AND STRESSRELATED BEHAVIORS IN DOGS Background The primary function of most domestic dogs has changed from utility to companionship. In order to be successful as a desirable companion, dogs need to be socialized and trained to be under their owner’s control. Traditional training methods are based on operant conditioning during which the animal learns that its responses to instructions or other stimuli have consequences called reinforcers. The latter can vary by their nature and occurrence. They can be the appearance or disappearance of appetent or aversive stimuli. There are 4 types of instrumental conditioning procedures: 2 types result in an increase in the rate of responses (positive reinforcement and negative reinforcement) and 2 types result in a decrease in the rate of responses (positive punishment and negative (withdrawal of) punishment.
Objectives To compare the effects of 2 training methods on both the behavioral welfare of the dog and the dog-owner relationship: the first method being based on positive reinforcement (appearance of an appetitive stimulus) and the second method based on negative reinforcement (disappearance of an aversive stimulus).
Procedure Behaviors linked to signs of stress and attentive behaviors toward the owner in 2 dog training schools, which used different methods, were compared. Walking on-leash activity and obeying the “sit” command were studied.
Results
Inclusions Three figures, 3 tables, 46 references.
Editor Annotation Most veterinarians have at least one dog trainer that they recommend to their clients. While positive reinforcement training has become very pervasive, older training methods employing negative reinforcement are still common. This study serves to gather scientific evidence as to which method is more stressful for the dog being trained. The author observed dog training classes in two different dog training schools, one using primarily positive reinforcement and one using primarily negative reinforcement. Information on canine body language signs indicative of stress and fear (e.g., lowered body, yawning, lip licking) as well as likelihood of engaging the owner visually were gathered as the dogs went through class. Dogs in the negative reinforcement class were significantly more likely to disengage from the owners (look away) than dogs which were being trained with positive reinforcement. In addition, dogs trained with positive reinforcement were significantly less likely to display certain stress signals such as lip licking and yawning. This study serves to add to the increasing amount of evidence that positive reinforcement training in general is less stressful for canine patients compared to negative reinforcement training. While operant conditioning can occur under stress, ideally situations where dogs are being taught to acquire new behaviors would promote as little stress as possible to maintain welfare and maximize learning efficiency. (LR) Deldalle S, Gaunet F. Effects of 2 training methods on stress-related behaviors of the dog (Canis familiaris) and on the dog-owner relationship. J Vet Behav 2014;9:58-65.
Dogs from the school using a negative reinforcement-based method demonstrated lowered body postures and signals of stress, whereas dogs from the school using a positive reinforcement-based method showed increased attentiveness toward their owner. However, neither method resulted in avoidance behaviors.
PROXIMAL RENAL TUBULAR DYSFUNCTION
Author Conclusion
Background
Training methods based on positive rein-
Copper-associated hepatitis (CAH) was
PAGE 3
first recognized in Bedlington terriers in 1975. Other affected breeds, including West Highland white terriers, Doberman pinschers, and Dalmatians, have since been identified. More recently, CAH has been reported in Labrador retrievers. Although a specific genetic mutation has only been described in Bedlington terriers, CAH is presumed to be hereditary in other affected breeds. Little is known about mechanisms of copper accumulation in non-Bedlington terrier breeds. Given that sex predisposition, signalment, and clinical course vary among breeds, it is probable that different genetic mutations are involved. Also unknown is whether copper can accumulate in other organs and result in dysfunction in those organs. Specific organ or tissue accumulation could vary depending on the mutation. There are a variety of copper storage disorders in humans. Wilson’s disease is the best-described genetic disorder that results in copper accumulation in the brain, eyes, and kidneys in addition to the liver. Approximately 40 to 50% of human patients present for neurologic disease or signs unrelated to hepatic copper accumulation. The clinical manifestations of copper-associated hepatitis in Labrador retrievers need further description.
Objectives To report clinical features, hepatic and renal histopathologic findings, tissue copper concentrations, and outcome of Labrador retrievers with CAH and proximal renal tubular disease.
Procedure Clinical, clinicopathologic, and light microscopic findings were retrospectively reviewed in 9 Labrador retrievers with renal glucosuria and biopsy-confirmed CAH. Rhodanine staining or atomic emission spectroscopy was performed on all hepatic samples and available renal tissue (4 dogs) to assess copper concentrations.
Results Eight dogs had a history of polyuria and polydipsia, and all dogs had increased serum bilirubin concentrations. Five dogs had hyperchloremic metabolic acidosis. Three dogs with acidemia had paradoxical alkalinuria. Renal tubular vacuolization, degeneration, and regeneration were
PAGE 4
A D V A N C E S
observed on light microscopy. All renal specimens had increased copper concentrations. Four dogs died within 10 days of diagnosis. One dog survived 2 months, and 4 dogs survived more than 1 year. Resolution of renal tubular dysfunction occurred within weeks to months in longterm survivors, including 2 that did not undergo immediate copper chelation.
Author Conclusion Labrador retrievers with CAH can develop clinical and laboratory evidence of renal tubular dysfunction in association with increased renal copper concentrations. Detection of renal glucosuria and increased also alanine aminotransferase (ALT) activity in a Labrador retriever is suggestive of CAH. Successful long-term outcome is possible with appropriate medical therapy.
Inclusions Four figures, 36 references.
Editor Annotation This small study is likely the tip of the iceberg with respect to the potential complication of copper-associated hepatitis in the dog. These researchers have demonstrated that renal disease is occurring with this copper accumulation process. The liver disease has been well established, but renal disease has only been suggested in the past. It is now confirmed in this group of dogs. Whenever copper-associated disease is suspected, renal function also should be evaluated. Some cases of Fanconi syndrome may be related to copper buildup in tubules. The authors suggest that this should be considered in all these cases. Veterinary medicine needs to be vigilant in monitoring the potential of copperassociated liver and renal disease in the dog. Other breeds are likely associated. In addition, copper may be a secondary problem in some primary liver disease processes. This is commonly a secondary problem in biliary obstructive diseases. (LDM) Langlois DK, Smedley RC, Schall WD, et al. Acquired proximal renal tubular dysfunction in 9 Labrador retrievers with copper-associated hepatitis (2006-2012). J Vet Intern Med 2013; 27:491-499.
IMMUNOTHERAPY RECOMMENDATIONS FROM FOUR COMMERCIAL LABORATORIES Background Allergen-specific immunotherapy (ASIT) may be prescribed to aid in the management of canine atopic dermatitis (AD). The formulation of the allergenic extract is customized for each dog based on allergen test results, history, and biology of airborne allergens. An intradermal test (IDT) or serum allergen test (SAT), or both, are performed to demonstrate allergen-specific immunoglobulin type E (IgE) directed against a panel or plant, fungi, mite, insect, and epidermal antigens important in the geographical region. An IDT is usually performed by a clinician using a panel of antigens that they have customized for their location. Within the same geographical region, these panels vary substantially, as do testing methodologies employed by different clinicians. In vitro IgE enzyme-linked immunosorbent assays (ELISAs) are offered by at least 6 commercial laboratories in the United States, operating without independent oversight of their quality control. Each laboratory divides the U.S. into zones and offers allergen-specific IgE tests for a standard panel of antigens for each zone. These laboratories differ in the number and identity of the antigens tested on standardized panels for a given geographical region. An antigen may be included as a mixture of phylogenetically related species by one laboratory, as individual species by a second laboratory, and not at all by a third. Allergens-specific IgE levels are interpreted as positive (abnormal elevation) if the optical density measured in the assay is above a cut-off level established by the laboratory. Positive allergens are candidates for inclusion in ASIT extract mixtures. Some of the antigens to which elevated allergen-specific IgE levels are reported may be excluded from the ASIT prescription if they are judged to have caused a false-positive reaction, are crossreactive with other antigens selected for inclusion, exceed the desired maximal number, or are otherwise deemed to be clinically irrelevant based on the patient’s history. Commercial SAT laboratories
offer technical assistance to guide veterinarians in formulating ASIT prescriptions based on these factors. Overall, the ASIT prescription for an atopic dog is influenced by the following factors: (1) the selection of allergens to be tested; (2) the intralaboratory and interlaboratory reliability of the testing; and (3) post-test interpretation and formulation. Each of these variables may affect the reproducibility of ASIT prescriptions for a given dog. Despite the potential for variability, the factors that may influence the composition of an ASIT prescription have received relatively little attention, and a variety of allergen-selection methods may be evaluated together in a single ASIT study. A rigorous evaluation of the reliability of IDT has not been published. There is often poor agreement between results of IDT and SAT performed concurrently on the same dog. Early studies demonstrated poor reliability of SAT; however, the testing methodologies may have changed since those studies were carried out.
Objectives To evaluate the agreement of diagnostic results and treatment recommendations of 4 serum IgE assays commercially available in the U.S.
Procedure Replicate serum samples from 10 atopic dogs were submitted to each of 4 laboratories for allergen-specific IgE assays. The interlaboratory agreement of standard regional panels and ensuing treatment recommendations were analyzed for agreement. Six comparisons of pairs of laboratories and overall agreement among laboratories were analyzed for ungrouped allergens (as tested) and also with allergens grouped according to reported crossreactivity and taxonomy.
Results The overall chance-corrected agreement of the positive/negative test results for ungrouped and grouped allergens was slight. Subset analysis of the laboratory pair with the highest level of diagnostic agreement found slight agreement for ungrouped plants and fungi, but substantial agreement for ungrouped mites. The overall agreement of the treatment recommendations was slight. Altogether, 85.1% of ungrouped allergen treatment recommendations were unique to one laboratory or another.
forcement are less stressful and potentially better for the welfare of dogs.
TRAINING METHODS AND STRESSRELATED BEHAVIORS IN DOGS Background The primary function of most domestic dogs has changed from utility to companionship. In order to be successful as a desirable companion, dogs need to be socialized and trained to be under their owner’s control. Traditional training methods are based on operant conditioning during which the animal learns that its responses to instructions or other stimuli have consequences called reinforcers. The latter can vary by their nature and occurrence. They can be the appearance or disappearance of appetent or aversive stimuli. There are 4 types of instrumental conditioning procedures: 2 types result in an increase in the rate of responses (positive reinforcement and negative reinforcement) and 2 types result in a decrease in the rate of responses (positive punishment and negative (withdrawal of) punishment.
Objectives To compare the effects of 2 training methods on both the behavioral welfare of the dog and the dog-owner relationship: the first method being based on positive reinforcement (appearance of an appetitive stimulus) and the second method based on negative reinforcement (disappearance of an aversive stimulus).
Procedure Behaviors linked to signs of stress and attentive behaviors toward the owner in 2 dog training schools, which used different methods, were compared. Walking on-leash activity and obeying the “sit” command were studied.
Results
Inclusions Three figures, 3 tables, 46 references.
Editor Annotation Most veterinarians have at least one dog trainer that they recommend to their clients. While positive reinforcement training has become very pervasive, older training methods employing negative reinforcement are still common. This study serves to gather scientific evidence as to which method is more stressful for the dog being trained. The author observed dog training classes in two different dog training schools, one using primarily positive reinforcement and one using primarily negative reinforcement. Information on canine body language signs indicative of stress and fear (e.g., lowered body, yawning, lip licking) as well as likelihood of engaging the owner visually were gathered as the dogs went through class. Dogs in the negative reinforcement class were significantly more likely to disengage from the owners (look away) than dogs which were being trained with positive reinforcement. In addition, dogs trained with positive reinforcement were significantly less likely to display certain stress signals such as lip licking and yawning. This study serves to add to the increasing amount of evidence that positive reinforcement training in general is less stressful for canine patients compared to negative reinforcement training. While operant conditioning can occur under stress, ideally situations where dogs are being taught to acquire new behaviors would promote as little stress as possible to maintain welfare and maximize learning efficiency. (LR) Deldalle S, Gaunet F. Effects of 2 training methods on stress-related behaviors of the dog (Canis familiaris) and on the dog-owner relationship. J Vet Behav 2014;9:58-65.
Dogs from the school using a negative reinforcement-based method demonstrated lowered body postures and signals of stress, whereas dogs from the school using a positive reinforcement-based method showed increased attentiveness toward their owner. However, neither method resulted in avoidance behaviors.
PROXIMAL RENAL TUBULAR DYSFUNCTION
Author Conclusion
Background
Training methods based on positive rein-
Copper-associated hepatitis (CAH) was
PAGE 3
first recognized in Bedlington terriers in 1975. Other affected breeds, including West Highland white terriers, Doberman pinschers, and Dalmatians, have since been identified. More recently, CAH has been reported in Labrador retrievers. Although a specific genetic mutation has only been described in Bedlington terriers, CAH is presumed to be hereditary in other affected breeds. Little is known about mechanisms of copper accumulation in non-Bedlington terrier breeds. Given that sex predisposition, signalment, and clinical course vary among breeds, it is probable that different genetic mutations are involved. Also unknown is whether copper can accumulate in other organs and result in dysfunction in those organs. Specific organ or tissue accumulation could vary depending on the mutation. There are a variety of copper storage disorders in humans. Wilson’s disease is the best-described genetic disorder that results in copper accumulation in the brain, eyes, and kidneys in addition to the liver. Approximately 40 to 50% of human patients present for neurologic disease or signs unrelated to hepatic copper accumulation. The clinical manifestations of copper-associated hepatitis in Labrador retrievers need further description.
Objectives To report clinical features, hepatic and renal histopathologic findings, tissue copper concentrations, and outcome of Labrador retrievers with CAH and proximal renal tubular disease.
Procedure Clinical, clinicopathologic, and light microscopic findings were retrospectively reviewed in 9 Labrador retrievers with renal glucosuria and biopsy-confirmed CAH. Rhodanine staining or atomic emission spectroscopy was performed on all hepatic samples and available renal tissue (4 dogs) to assess copper concentrations.
Results Eight dogs had a history of polyuria and polydipsia, and all dogs had increased serum bilirubin concentrations. Five dogs had hyperchloremic metabolic acidosis. Three dogs with acidemia had paradoxical alkalinuria. Renal tubular vacuolization, degeneration, and regeneration were
PAGE 4
A D V A N C E S
observed on light microscopy. All renal specimens had increased copper concentrations. Four dogs died within 10 days of diagnosis. One dog survived 2 months, and 4 dogs survived more than 1 year. Resolution of renal tubular dysfunction occurred within weeks to months in longterm survivors, including 2 that did not undergo immediate copper chelation.
Author Conclusion Labrador retrievers with CAH can develop clinical and laboratory evidence of renal tubular dysfunction in association with increased renal copper concentrations. Detection of renal glucosuria and increased also alanine aminotransferase (ALT) activity in a Labrador retriever is suggestive of CAH. Successful long-term outcome is possible with appropriate medical therapy.
Inclusions Four figures, 36 references.
Editor Annotation This small study is likely the tip of the iceberg with respect to the potential complication of copper-associated hepatitis in the dog. These researchers have demonstrated that renal disease is occurring with this copper accumulation process. The liver disease has been well established, but renal disease has only been suggested in the past. It is now confirmed in this group of dogs. Whenever copper-associated disease is suspected, renal function also should be evaluated. Some cases of Fanconi syndrome may be related to copper buildup in tubules. The authors suggest that this should be considered in all these cases. Veterinary medicine needs to be vigilant in monitoring the potential of copperassociated liver and renal disease in the dog. Other breeds are likely associated. In addition, copper may be a secondary problem in some primary liver disease processes. This is commonly a secondary problem in biliary obstructive diseases. (LDM) Langlois DK, Smedley RC, Schall WD, et al. Acquired proximal renal tubular dysfunction in 9 Labrador retrievers with copper-associated hepatitis (2006-2012). J Vet Intern Med 2013; 27:491-499.
IMMUNOTHERAPY RECOMMENDATIONS FROM FOUR COMMERCIAL LABORATORIES Background Allergen-specific immunotherapy (ASIT) may be prescribed to aid in the management of canine atopic dermatitis (AD). The formulation of the allergenic extract is customized for each dog based on allergen test results, history, and biology of airborne allergens. An intradermal test (IDT) or serum allergen test (SAT), or both, are performed to demonstrate allergen-specific immunoglobulin type E (IgE) directed against a panel or plant, fungi, mite, insect, and epidermal antigens important in the geographical region. An IDT is usually performed by a clinician using a panel of antigens that they have customized for their location. Within the same geographical region, these panels vary substantially, as do testing methodologies employed by different clinicians. In vitro IgE enzyme-linked immunosorbent assays (ELISAs) are offered by at least 6 commercial laboratories in the United States, operating without independent oversight of their quality control. Each laboratory divides the U.S. into zones and offers allergen-specific IgE tests for a standard panel of antigens for each zone. These laboratories differ in the number and identity of the antigens tested on standardized panels for a given geographical region. An antigen may be included as a mixture of phylogenetically related species by one laboratory, as individual species by a second laboratory, and not at all by a third. Allergens-specific IgE levels are interpreted as positive (abnormal elevation) if the optical density measured in the assay is above a cut-off level established by the laboratory. Positive allergens are candidates for inclusion in ASIT extract mixtures. Some of the antigens to which elevated allergen-specific IgE levels are reported may be excluded from the ASIT prescription if they are judged to have caused a false-positive reaction, are crossreactive with other antigens selected for inclusion, exceed the desired maximal number, or are otherwise deemed to be clinically irrelevant based on the patient’s history. Commercial SAT laboratories
offer technical assistance to guide veterinarians in formulating ASIT prescriptions based on these factors. Overall, the ASIT prescription for an atopic dog is influenced by the following factors: (1) the selection of allergens to be tested; (2) the intralaboratory and interlaboratory reliability of the testing; and (3) post-test interpretation and formulation. Each of these variables may affect the reproducibility of ASIT prescriptions for a given dog. Despite the potential for variability, the factors that may influence the composition of an ASIT prescription have received relatively little attention, and a variety of allergen-selection methods may be evaluated together in a single ASIT study. A rigorous evaluation of the reliability of IDT has not been published. There is often poor agreement between results of IDT and SAT performed concurrently on the same dog. Early studies demonstrated poor reliability of SAT; however, the testing methodologies may have changed since those studies were carried out.
Objectives To evaluate the agreement of diagnostic results and treatment recommendations of 4 serum IgE assays commercially available in the U.S.
Procedure Replicate serum samples from 10 atopic dogs were submitted to each of 4 laboratories for allergen-specific IgE assays. The interlaboratory agreement of standard regional panels and ensuing treatment recommendations were analyzed for agreement. Six comparisons of pairs of laboratories and overall agreement among laboratories were analyzed for ungrouped allergens (as tested) and also with allergens grouped according to reported crossreactivity and taxonomy.
Results The overall chance-corrected agreement of the positive/negative test results for ungrouped and grouped allergens was slight. Subset analysis of the laboratory pair with the highest level of diagnostic agreement found slight agreement for ungrouped plants and fungi, but substantial agreement for ungrouped mites. The overall agreement of the treatment recommendations was slight. Altogether, 85.1% of ungrouped allergen treatment recommendations were unique to one laboratory or another.