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Abstract

Objective—To examine the relationship between lameness and milk yield in dairy cows.

Design—Cohort study.

Animals—531 dairy cows.

Procedure—Cows affected with lameness were classified into 1 of 3 groups on the basis of type of diseases or lesions observed, including interdigital phlegmon (foot rot), papillomatous digital dermatitis (foot warts), or claw lesions. Cows not affected with lameness were classified as healthy. From Dairy Herd Improvement Association records, 305-day mature equivalent milk yield data were collected at the end of lactation or when the cow left the herd. Milk yield was compared between cows affected with lameness and healthy cows.

Results—167 (31%) cows were affected with lameness during lactation. Lame cows had claw lesions (60%), papillomatous digital dermatitis (31%), or interdigital phlegmon (9%). Milk yield in lame cows with interdigital phlegmon (mean, 17,122 lb) was significantly less, compared with healthy cows (19,007 lb).

Conclusions and Clinical Relevance—In this herd, interdigital phlegmon was associated with a 10% decrease in milk production. Lame cows with claw lesions or papillomatous digital dermatitis produced less milk than healthy cows, but the difference was not significant. (J Am Vet Med Assoc 2002;220:640–644)

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in Journal of the American Veterinary Medical Association

Abstract

Objective—To examine the relationship between lameness and the duration of the interval from calving to subsequent conception in lactating dairy cows.

Design—Cohort study.

Animals—837 dairy cows.

Procedure—Cows affected with lameness were classified into 1 of 4 groups on the basis of types of disease or lesions observed, including foot rot, papillomatous digital dermatitis, claw lesions, or multiple lesions. Cows not affected with lameness were classified as healthy. Time from calving to conception was compared between lame cows and healthy cows.

Results—254 (30%) cows were affected with lameness during lactation. Most lame cows (59%) had claw lesions. Lame cows with claw lesions were 0.52 times as likely to conceive as healthy cows. Median time to conception was 40 days longer in lame cows with claw lesions, compared with healthy cows. Number of breedings per conception for lame cows with claw lesions was significantly higher than that for healthy cows.

Conclusion and Clinical Relevance—Claw lesions were the most important cause of lameness, impairing reproductive performance in dairy cows, as indicated by a higher incidence of affected cows and a greater time from calving to conception and a higher number of breedings required per conception, comp ared with healthy cows. (J Am Vet Med Assoc 2001; 218:1611–1614)

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in Journal of the American Veterinary Medical Association

Abstract

Objective—To analyze the expression of versican and hyaluronan in melanocytomas and malignant melanomas of dogs, to correlate their expression with expression of the hyaluronan receptor CD44, and to identify enzymes responsible for the synthesis and degradation of hyaluronan in canine dermal fibroblasts and canine melanoma cell lines.

Sample Population—35 biopsy specimens from melanocytic tumors of dogs, canine primary dermal fibroblasts, and 3 canine melanoma cell lines.

Procedures—Versican, hyaluronan, and CD44 were detected in tumor samples by use of histochemical or immunohistochemical methods. Expression of hyaluronan-metabolizing enzymes was analyzed with a reverse transcriptase–PCR assay.

Results—Versican was found only in some hair follicles and around some blood vessels in normal canine skin, whereas hyaluronan was primarily found within the dermis. Hyaluronan was found in connective tissue of the oral mucosa. Versican and, to a lesser extent, hyaluronan were significantly overexpressed in malignant melanomas, compared with expression in melanocytomas. No significant difference was found between malignant tumors from oral or cutaneous origin. The expression of both molecules was correlated, but hyaluronan had a more extensive distribution than versican. Versican and hyaluronan were mainly associated with tumor stroma. Canine fibroblasts and melanoma cell lines expressed hyaluronan synthase 2 and 3 (but not 1) and hyaluronidase 1 and 2.

Conclusions and Clinical Relevance—Versican may be useful as a diagnostic marker for melanocytic tumors in dogs. Knowledge of the enzymes involved in hyaluronan metabolism could reveal new potential therapeutic targets.

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in American Journal of Veterinary Research

Abstract

Objective—To determine effects of 2 doses of caffeine on metabolic variables in neonata pigs with peripartum asphyxia

Animals—180 neonatal pigs

Procedures—Neonatal pigs were assigned to 2 groups (groups P and F) on the basis of results for a vitality scale (passed or failed, respectively). Within each group, there were 3 subgroups of 30 pigs each. Within each group, the 3 subgroups received a placebo that consisted of an empty gelatin capsule, a gelatin capsule that contained 20 mg of caffeine, and a gelatin capsule that contained 35 mg of caffeine, respectively; all capsules were administered orally (0 hours). Blood samples were collected immediately before and 24 hours after capsule administration.

Results—Pigs in groups P and F that received 20 or 35 mg of caffeine had significant increases in triglyceride concentrations. All pigs in groups P and F had a significant decrease in lactate concentrations, although the placebo-treated pigs in group F had larger decreases than did the group F pigs treated with 20 or 35 mg of caffeine. Glucose concentrations increased significantly in group F pigs treated with 20 or 35 mg of caffeine (30% and 50%, respectively), whereas glucose concentrations remained unchanged in group P pigs. In pigs treated with 35 mg of caffeine, the final weight obtained for group F was approximately 8% lower than that obtained for group P

Conclusions and Clinical Relevance—Administering caffeine immediately after birth to neonatal pigs with severe oxygen restriction resulted in significant improvements in metabolic variables. (Am J Vet Res 2010;71:1214-1219)

Full access
in American Journal of Veterinary Research