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Summary

The diffusing capacity for carbon monoxide (dl co ) and the functional residual capacity (frc) of the lung were measured in 5 healthy Thoroughbreds before and after instillation of autologous blood into their lungs, in an attempt to develop a method to quantitate extravascular blood in the lungs of horses with exercise-induced pulmonary hemorrhage. Mean (± SD) baseline values of dl co and frc were 333.8 ± 61.9 ml/min/mm of Hg and 21.464 ± 4.156 L, respectively. Blood instillation resulted in decreases in dl co and frc. The paradoxic decrease in dl co (we were expecting to find an increase owing to blood in the airspaces, as has been reported in people) appears to be associated with the bronchoscopic procedure and with presence of blood in the airways. We concluded that rebreathing dl co measurements were not effective for detecting blood introduced bronchoscopically into the lungs of horses.

Free access
in American Journal of Veterinary Research

Summary

Chemotactic locomotion and luminol-dependent chemiluminescence of neutrophils, mitogen-induced lymphocyte blastogenesis, serum cortisol concentration, immunoglobulin quantification, and leukocyte counts were determined to evaluate the effect of a single strenuous exercise in horses. Increased serum cortisol concentration (P < 0.01) and an increased neutrophil-to-lymphocyte ratio (P < 0.05) indicated that horses had been stressed. The chemotactic index and peak chemiluminescence production decreased significantly (P < 0.05 and P < 0.01, respectively) 1 day after exercise. Mitogen-induced blastogenesis of lymphocytes and serum immunoglobulin values remained unchanged in response to exercise. Results of this study indicated that a single bout of exercise may transiently impair neutrophil antimicrobial functions and nonspecific defense mechanisms, but not specific immunity in horses.

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in American Journal of Veterinary Research

SUMMARY

A new serotype of calicivirus was isolated from California sea lions (Zalophus californianus) with severe vesicular disease. Neutralizing antibodies were found in 27 of 82 (32.9%) serum samples from California sea lions and in 15 of 146 (10.3%) serum samples from Steller sea lions (Eumetopias jubatus) tested. The seropositive animals were widely dispersed along the margins of the eastern Pacific basin, from the Bering Sea to the Santa Barbara Channel. Seropositive samples were found from as early as 1976 through the present time. This new calicivirus serotype, San Miguel sea lion virus type 13, was inoculated into weaned pigs, resulting in induction of severe vesicular disease, which spread to all pigs, including uninoculated pen contacts. Virus was continually shed by most of the pigs throughout the 2-week duration of the experiment.

Free access
in American Journal of Veterinary Research
in Journal of the American Veterinary Medical Association

Abstract

Objective

To evaluate transabdominal ultrasound-guided amniocentesis for detection of equid herpesvirus 1 (EHV-1)-induced fetal infection in utero.

Animals

4 Welsh Mountain mares.

Procedure

Pregnant mares were inoculated intranasally with EHV-1 during the ninth month of gestation. Amniocentesis was initiated on postinoculation day (PID) 12, and was performed at 2- to 3-day intervals in standing mares under deep sedation. Amniotic fluid samples were tested by virus isolation (VI), polymerase chain reaction (PCR), and immunoperoxidase cytologic examination (IC) for detection of EHV-1.

Results

Exposure to EHV-1 in the ninth month of gestation resulted in nasal shedding of infective virus, establishment of cell-associated viremia, and seroconversion. Equid herpesvirus 1 was detected by VI, PCR, and IC in amniotic fluid collected on PID 14 from 1 mare and on PID 16 and 17 from a second mare. Specimens of amniotic fluid from a third mare were VI negative until PID 18, when collections ceased, although this mare subsequently aborted an EHV-1-infected fetus on PID 28. The fourth mare aborted an EHV-1 infected fetus on PID 14. The 2 mares with VI-positive amniotic fluid were each carrying an EHV-1 infected fetus in utero, confirmed by examination of the uterus, placenta, and fetus, using specific immunohistochemistry and in situ hybridization. Endothelial cells in the endometrium and allantochorion were often virus-infected, with accompanying vascular lesions. The fetus had been infected via the chorionic vasculature in the first and fourth mares, and by inhalation of infected amniotic fluid in the second mare.

Conclusion

Amniocentesis permits specific detection of EHV-1-induced fetal infection in utero.

Clinical Relevance

Amniocentesis may have a clinical role in the specific identification and isolation of mares carrying virus-infected fetuses during EHV-1- induced abortion epizootics. (Am J Vet Res 1997;58:997–1002)

Free access
in American Journal of Veterinary Research

Abstract

Objective—To determine prevalence of a radiographic caudolateral curvilinear osteophyte (CCO) on the femoral neck in various breeds and age groups of dogs and to evaluate its contemporaneous relationship with degenerative joint disease (DJD) and distraction index (DI).

Design—Cross-sectional prevalence study.

Animals—25,968 dogs, including 3,729 German Shepherd Dogs, 4,545 Golden Retrievers, 6,277 Labrador Retrievers, and 1,191 Rottweilers.

Procedure—Data from the University of Pennsylvania Hip Improvement Program database were analyzed, including ventrodorsal hip-extended, compression, and distraction radiographs. The CCO and radiographic signs of DJD were considered independent events and were interpreted as either present or absent. Statistical methods were used to evaluate the CCO as a possible risk factor for DJD and assess its association with DI, as measured by use of distraction radiography.

Results—When all breeds were pooled, DJD was detected in 8.6% of dogs, and the CCO was detected in 21.6% of dogs. Among dogs with a CCO, 25.1% had radiographic evidence of DJD. Among dogs without a CCO, only 4% had DJD. Dogs with a CCO were 7.9 times as likely to have DJD as were those without a CCO. Additionally, DI, weight, and age were significant risk factors for the CCO.

Conclusion and Clinical Relevance—Results confirm the contemporaneous association between the CCO and DJD and that passive hip laxity, as measured by use of the DI, is associated with both the CCO and DJD. (J Am Vet Med Assoc 2002;220:472–476)

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine duration of administration, complications, and frequency of aortic thromboembolism associated with administration of low molecular weight heparin (dalteparin) in cats.

Design—Retrospective study.

Animals—57 cats treated with dalteparin.

Procedure—Data were recorded from the medical records of cats treated with dalteparin, and owners were contacted by telephone for information regarding ease of administration and possible adverse effects.

Results—Dalteparin was easily administered by owners. Median dose was 99 U/kg (45 U/lb) once or twice daily. Bleeding complications were infrequent. Of 43 cats with cardiomyopathy that received owner-administered dalteparin for a median follow-up time of 172 days, 8 cats developed documented or possible arterial thromboembolism.

Conclusions and Clinical Relevance—Dalteparin was easily administered by owners and was well tolerated by cats. Whether dalteparin administration can reduce the frequency or severity of arterial thromboembolism is not yet known. (J Am Vet Med Assoc 2004;225:1237–1241)

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To evaluate hip joint laxity in 10 breeds of dogs via 2 radiographic techniques.

Animals—500 clinically normal dogs.

Design—Prospective study.

Procedure—Radiographs obtained via routine hip joint evaluations performed in sedated dogs of 10 popular breeds were randomly selected from a database. Measurements of distraction index (DI) and hipextended index (HEI) on 1 hip joint radiograph randomly chosen from each dog were made.

Results—Mean age of dogs was 20.7 months. Mean HEI was 0.17 (range, 0.0 to 0.72) and mean DI was 0.44 (range, 0.07 to 0.96). Borzois had uniformly tight hip joints as judged by use of both methods and were considered the gold standard by which hip joint laxity was judged (all Borzois had DI ≤ 0.32). Overall, DI was significantly greater than HEI. Within each breed, mean DI was always greater than mean HEI. Significant differences were detected among breeds for HEI; however, compared with DI, the magnitude of differences among breeds was less.

Conclusions and Clinical Relevance—Distraction radiography detected the greatest range and magnitude of passive hip laxity in the 10 breeds of dogs. The difference in values between breeds known to have high prevalence of canine hip dysplasia and those in Borzois was greater for DI than for HEI. Breeds must be evaluated individually because of inherent differences in hip joint laxity. ( J Am Vet Med Assoc 2004; 224:542–546)

Full access
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE To estimate costs associated with prevention and treatment of bovine respiratory disease (BRD) in preweaned calves on US beef cow–calf operations.

DESIGN Cross-sectional survey.

SAMPLE 43 beef cow–calf producers whose operations had a history of BRD in preweaned calves.

PROCEDURES Mail and electronic surveys were developed and administered to producers in Nebraska, North Dakota, and South Dakota to obtain information regarding costs of BRD prevention and treatment. Descriptive statistics were generated. Mixed linear regression models were used to assess factors associated with the costs of vaccines, medicine, and labor and percentage time spent on prevention and treatment of BRD in cows, replacement heifers, and preweaned calves.

RESULTS 7 mail and 36 electronic surveys were completed. Median annual costs for BRD vaccines were $2.25, $4.00, and $6.25/animal, and median annual labor costs for vaccination were $4.58, $3.00, and $5.00/animal for cows, heifers, and preweaned calves, respectively. Median annual costs for medicine and labor to treat preweaned calves for BRD were $11.00 and $15.00/ affected calf, respectively. Adjusted mean annual BRD vaccine cost for preweaned calves ($7.67/animal) was significantly greater than that for cows ($3.18/animal) and heifers ($4.48/animal).

CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that labor costs associated with BRD vaccination and treatment were similar to or exceeded the cost of vaccines and medicine, and most of those labor costs were associated with gathering and sorting cattle. Therefore, costs associated with labor as well as medicine and vaccines should be considered during the development of BRD prevention and treatment plans.

Full access
in Journal of the American Veterinary Medical Association