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Abstract

Objective—To determine whether use of serologic evaluation of a sentinel sample of calves or cows for antibodies against bovine viral diarrhea virus (BVDV) would accurately predict whether an animal persistently infected with BVDV could be detected in beef herds.

Sample Population—27 cow-calf herds in which the status of persistently infected calves was not known and 11 herds known to have persistently infected calves.

Procedure—Detection of persistently infected calves was determined through immunohistochemical testing of tissue obtained at necropsy of all calves that died during calving season and skin (ear notch) specimens obtained from all young stock in the fall of 2002. Serum samples were collected from 30 springborn calves and 10 mature cows.

Results—Optimum serologic test performance at time of weaning was detected when 10 calves were evaluated. At least 3 of 10 randomly selected calves were likely to have a titer > 1:1,000 against BVDV type I or II in 53% of herds in which a persistently infected calf was detected during that year (sensitivity, 53%). However, at least 3 of 10 randomly selected calves were also likely to have a titer > 1:1,000 in 20% of herds that did not have a persistently infected calf detected during that year (specificity, 80%).

Conclusions and Clinical Relevance—Despite the use of a number of various cutoff values and sample sizes, serologic evaluation of a small number of calves or cows could not be used to accurately predict the presence of persistently infected cattle in a herd. (Am J Vet Res 2005;66:825–834)

Full access
in American Journal of Veterinary Research

Objective

To assess the value of CBC as a preoperative test in healthy horses undergoing cryptorchidectomy.

Design

Retrospective study.

Animals

117 horses.

Procedure

Medical records were reviewed to identify horses that had had cryptorchidectomy. Of the 117 horses identified, 102 were found that did not have a known medical condition believed to adversely affect surgery. Preoperative CBC was assessed in terms of abnormalities detected and effects of these abnormalities on development of complications during and after surgery and patient management.

Results

Of 102 CBC performed, 55 contained abnormalities. Mild neutrophilia was detected in 40 horses. Of the remaining 15 horses with abnormal CBC, 8 had abnormalities that were considered potentially important. Changes in patient management and development of surgical complications were not associated with these 8 horses. Surgical complications were defined as intraoperative changes in blood pressure, excessive blood loss, development of postanesthetic myopathies, and postoperative wound or respiratory tract infections. Surgical complications developed in 17 horses. Of these, 6 horses had an abnormal CBC that was indicative of mild neutrophilia. Positive and negative predictive values of preoperative CBC on development of perioperative complications were 0.11 and 0.77, respectively.

Clinical Implications

On the basis of findings in our study, determination of preoperative CBC does not predict development of complications during or after surgery and does not alter patient management. (J Am Vet Med Assoc 1997;211:887–888)

Free access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine risk factors associated with Cryptococcus gattii infection in dogs and cats residing on Vancouver Island in British Columbia, Canada.

Design—Matched case-control study.

Animals—20 dogs and 29 cats with C gattii infection and matched controls.

Procedure—Dogs and cats with a confirmed or probable diagnosis of cryptococcosis resulting from infection with C gattii were enrolled by veterinarians, and owners completed a questionnaire designed to obtain information pertaining to potential risk factors for the disease. Owners of matched control animals were also interviewed. Odds ratios and 95% confidence intervals or paired t tests were calculated to determine significant associations.

Results—Animals were enrolled during 2 noncontiguous periods in August 2001 to February 2002 (8 dogs and 9 cats enrolled) and May to December 2003 (12 dogs and 20 cats enrolled). Risk factors significantly associated with development of cryptococcosis included residing within 10 km of a logging site or other area of commercial soil disturbance, above-average level of activity of the animal, travelling of the animal on Vancouver Island, hunting by the animal, and owners hiking or visiting a botanic garden.

Conclusions and Clinical Relevance—Results indicated that dogs and cats that were active or that lived near a site of commercial environmental disturbance had a significantly increased risk of developing C gattii infection. Veterinarians should communicate these risks to owners in context because cryptococcosis was an uncommon disease in this population.

Full access
in Journal of the American Veterinary Medical Association

Objective

To compare sensitivity for diagnosing Tritrichomonas foetus infection in bulls using 2 sampling tools and to calculate negative predictive values for infection.

Design

Randomized clinical trial.

Animals

30 Bos taurus bulls naturally or experimentally infected with T foetus.

Procedure

Preputial scrapings were obtained once/wk for 6 weeks using an artificial insemination pipette and a metal brush; which tool was used first for each bull was randomly determined. Samples were collected first from the left side of the prepuce and then from the right side and placed in commercially available transport media. χ2 Values and confidence limits were adjusted for effect of clustering of results by bull.

Results

Significant differences in sensitivity of results were not found between samples collected using the brush or pipette. Using the pipette, sensitivity was estimated to be 91.6% (95% confidence interval, 84.3 to 95.7%); negative predictive values ranged from 41 to 99% for prevalence of infection of 90 to 5%, respectively. Sensitivity was 88.8% for first sample obtained and 96.1% for second sample obtained.

Conclusions and Clinical Relevance

Collection of preputial scrapings with an artificial insemination pipette or a metal brush and use of a commercially available culture system can provide a sensitive diagnostic test for T foetus infection in bulls. Calculated negative predictive values indicated that 1 or 2 tests would suffice in most clinical situations. For bulls from herds in which T foetus is endemic, 2 to 4 tests/bull may be required to ensure that each bull is not infected. (J Am Vet Med Assoc 1999;215:231–235)

Free access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To compare pathologic changes of the horizontal ear canal associated with chronic severe otitis externa between Cocker Spaniels and dogs of other breeds.

Design—Retrospective study.

Animals—80 dogs with severe otitis externa that required total ear canal ablation with lateral bulla osteotomy.

Procedure—Medical records were reviewed for breed, sex, and age at time of surgery. Histologic specimens from the horizontal ear canal were evaluated by a single examiner for overall tissue response pattern and scored for sebaceous gland hyperplasia, ceruminous gland hyperplasia, ceruminous gland ectasia, fibrosis, pigment-laden macrophages, and osseous metaplasia.

Results—48 of 80 (60%) dogs were Cocker Spaniels. Thirty-five of 48 (72.9%) Cocker Spaniels had a predominately ceruminous tissue response pattern; only 9 of 32 (28.1%) dogs of other breeds had the same pattern. Other breeds most commonly had a pattern dominated by fibrosis (n = 13 [40.6%]); fibrosis was the predominant pattern in only 4 of 48 (8.3%) Cocker Spaniels. Discriminant analysis and K-means clustering of 4 histopathologic criteria correctly classified 75% of the dogs as Cocker Spaniels or all other breeds.

Conclusions and Clinical Relevance—Cocker Spaniels are at increased risk for chronic severe otitis externa requiring total ear canal ablation with lateral bulla osteotomy, indicating that earlier and more aggressive management of the primary otitis externa and secondary inflammation is warranted in this breed. Cocker Spaniels with chronic severe otitis externa have distinct differences in pathologic characteristics of the horizontal ear canal, compared with other breeds. (J Am Vet Med Assoc 2002;221: 1000–1006)

Full access
in Journal of the American Veterinary Medical Association

SUMMARY

Alterations in serum lipid and lipoprotein concentrations in ponies with experimentally induced liver disease were investigated. Hepatocellular damage was induced, using a nonlethal dose of carbon tetrachloride. In a separate group of ponies, obstructive jaundice was induced by surgical ligation of the common bile duct. Over a 6-day period, blood samples were obtained from ponies after treatment with carbon tetrachloride and for 12 days in ponies subjected to surgery. Serum cholesterol and triglyceride concentrations were unaffected in both groups of ponies, except for significantly (P < 0.01) high triglyceride concentration in ponies of the ligated group during the second postsurgical week. This increase was most likely attributable to anorexia observed during that period. Hyperbilirubinemia was observed early in ponies of the ligated group; most of the bilirubin was of the conjugated type. Using electrophoretic and ultracentrifugal methods, serum lipoprotein alterations were detected only in ponies of the ligated group. Increases of very low-density and low-density lipoprotein cholesterol concentrations and decrease in high-density lipoprotein cholesterol concentration were found. Although no changes were seen in total serum cholesterol concentration, a redistribution of lipoprotein cholesterol was observed in ponies of the ligated group. Similar alterations in lipoprotein distribution have been found in dogs, rats, and human beings with obstructive jaundice and cholestasis. The association between serum lecithin:cholesterol acyl transferase activities and these lipoprotein alterations remains to be elucidated.

Free access
in American Journal of Veterinary Research

Abstract

Objective—To determine the sensitivity of a real-time PCR assay for the detection of Tritrichomonas foetus in protozoal cultures of preputial scraping samples pooled from up to 25 bulls and to determine the specificity of that assay for detection of T foetus in cultures for individual animals.

Design—Cross-sectional study.

Animals—188 bulls and 150 steers.

Procedures—Preputial scraping samples were collected, placed in a culture kit, and incubated at 37°C for 7 days. Cultures for individual animals were tested for T foetus by means of a real-time PCR assay. Pools of protozoal cultures were made by including fixed aliquots of samples with known positive and negative results in ratios of 1:2, 1:3, 1:5, 1:10, 1:15, 1:20, and 1:25. Specificities of the real-time PCR assay and culture for detection of T foetus in samples obtained from individual animals and sensitivity of real-time PCR assay for each evaluated pool ratio were determined.

Results—Specificity estimates for culture and the real-time PCR assay for detection of T foetus in preputial scraping samples for individual animals were not significantly different (98.8% and 100%, respectively). Sensitivities of the real-time PCR assay for the various pooled samples with known positive and negative T foetus results were not significantly different; overall sensitivity of the assay was 94%.

Conclusions and Clinical Relevance—Results indicated the evaluated real-time PCR assay had high specificity and good sensitivity for the detection of T foetus in pooled protozoal cultures of preputial scraping samples obtained from up to 25 animals.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To describe the degree of and variability in the level of client compliance and identify determinants of client compliance with short-term administration of antimicrobial medications to dogs.

Design—Prospective study.

Sample Population—90 owners of dogs prescribed antimicrobials.

Procedure—Eligible clients were invited to participate when antimicrobial medications were dispensed. Data were collected during a follow-up appointment by use of a client questionnaire, residual pill count, and return of an electronic medication monitoring device. Attending veterinarians also completed a questionnaire that asked them to predict client compliance. Methods of assessing compliance were compared with nonparametric tests. Generalized estimating equations were used to investigate potential determinants of compliance.

Results—Median compliance rates of 97% of prescribed container openings, 91% of days when the correct number of doses were given, and 64% of doses given on time as assessed by the electronic medication monitoring devices were significantly lower than the median compliance rates of 100% for client self-report of missing doses and pill count. Veterinarians were unable to predict client compliance. The dosage regimen significantly determined compliance. Clients giving antimicrobials once or twice daily were 9 times more likely to be 100% compliant, compared with 3 times daily dosing.

Conclusions and Clinical Relevance—The combination of reported missed doses and pill counts was a significant predictor of compliance as measured by electronic monitoring. Electronic monitoring caps provided useful information only when they were used appropriately. Asking clients about missed doses and performing pill counts are the most practical assessments of compliance in practice. (J Am Vet Med Assoc 2005;226:567–574)

Full access
in Journal of the American Veterinary Medical Association

Summary

Desoxycorticosterone pivalate was administered im to juvenile Beagles at 0, 2.2, 6.6, or 11 mg/kg of body weight daily over a consecutive 3-day period every 28 days (equivalent to a cumulative monthly dosage of 0, 6.6, 19.8, or 33 mg/kg) for 6 months. Polyuria, polydipsia, and decreases in serum potassium and bun concentrations were detected while the dogs were being treated. Transient increases in serum sodium concentrations also were detected. The treated males had significant decreases in body weight gain, resulting in an 18% decrease in body weight in the 11-mg/kg dosage group, compared with the controls. The weights of the adrenal glands, epididymides, and testes also were lower in the treated males. Organ weights for the 2.2, 6.6, and 11-mg/kg dosage groups were: 86, 79, and 69%, respectively, of the controls (adrenal glands); 80, 70, and 68%, respectively, of the controls (epididymides); and, 79, 75, and 67%, respectively, of the controls (testes). When normalized to body weight, these decreases in organ weight were still dosage-dependent, but the differences were less remarkable. In contrast, the relative weight (to body weight) of the kidneys (males and females) and of the thyroid and parathyroid glands (males) were higher dosage-dependently. All of the treatment-related effects, other than organ and body weight changes, appeared to be reversible following the cessation of treatment. On the basis of these results, it was concluded that treatment with desoxycorticosterone pivalate could be tolerated, even when given at dosages 15-fold the therapeutic dosage of 2.2 mg/kg every 25 days.

Free access
in American Journal of Veterinary Research