Search Results

You are looking at 1 - 3 of 3 items for

  • Author or Editor: Lawrence J. Hutchinson x
  • Refine by Access: Content accessible to me x
Clear All Modify Search

Objective

To determine what effect participation by veterinarians in a dairy production medicine continuing education course would have on herd performance and management practices of client herds.

Design

Cohort study.

Sample Population

56 dairy herds for which health services were provided by veterinarians enrolled in a dairy production medicine continuing education program (treatment herds) and 97 dairy herds for which health services were provided by veterinarians not enrolled in the program (control herds).

Procedure

Management practices were evaluated every year for 4 years (1991 through 1994) by mail questionnaire. Herd performance was evaluated by reviewing Dairy Herd Improvement Association records.

Results

Mean age at first calving for the treatment herds decreased by 2 months over the course of the study. At the end of the study, treatment herds were 3 times more likely to review herd performance with their veterinarian and monitor heifer growth, and 2 times more likely to set goals and conduct adequate estrus detection than were control herds.

Clinical Implications

Effective professional continuing education in production medicine can have a positive impact on health and performance of client herds. (J Am Vet Med Assoc 1996;209:1086-1089)

Free access
in Journal of the American Veterinary Medical Association

Summary

Overall, 74% of the tissue specimens that meat inspectors at a large Pennsylvania packing plant identified as lesions of swine mycobacteriosis yielded Mycobacterium avium on bacteriologie culture. Histopathologic lesions compatible with mycobacteriosis were identified in 83% of the specimens; only 12% of the specimens had acid-fast staining organisms.

Free access
in Journal of the American Veterinary Medical Association

Summary

An elisa containing lipoarabinomannan (lam) antigen was used to detect antibodies in milk and serum for diagnosis of Mycobacterium paratuberculosis infection in dairy cattle. In experiment 1, milk and serum samples were obtained from 25 cows, and subjected to lam elisa testing immediately, and after 1 year of storage at −70 C. Milk samples, with and without a commonly used chemical preservative, were tested. There was no significant difference in lam elisa results between fresh and frozen samples or between preserved and unpreserved milk samples. In experiment 2, milk samples were collected daily from 30 cows over a 14-day period. The day-to-day coefficient of variation was 0.19 for milk lam elisa and was 0.15 for serum lam elisa, with no statistically significant time effect detected. In experiment 3, single milk, serum, and fecal samples were obtained from 764 cows. The fecal samples were cultured for M paratuberculosis to identify infected cows, and the serum and milk samples were subjected to lam elisa testing. Results were compared, using the area under the receiver operating characteristic curves. The milk lam elisa had specificity (± 95% confidence limits) of 87 ± 8.1% when the cutoff was set at 50% sensitivity, and specificity of 83 ± 9.1% when sensitivity was set at 60%. The area under the receiver operating characteristic curve was 0.85 ± 0.03 for the milk elisa and 0.75 ± 0.02 for the serum elisa. In this population of cattle, the milk lam elisa had comparable accuracy to serum lam elisa, although the milk lam elisa was slightly less reproducible (higher coefficient of variation).

Free access
in American Journal of Veterinary Research