Effect of infection with bovine leukemia virus on milk production in Michigan dairy cows.
J Dairy Sci
; 99(3): 2043-2052, 2016 Mar.
Article
em En
| MEDLINE
| ID: mdl-26723124
ABSTRACT
The objective of this study was to determine the association between individual cow-level milk production and bovine leukemia virus (BLV) infection as measured by milk BLV-ELISA. Dairy Herd Improvement technicians collected milk samples from 10 cows from each of first, second, third, and 4+ parity cows in 105 Holstein herds with ≥ 120 milking cows. Milk samples were tested for the presence of anti-BLV antibodies by ELISA. Additional data regarding the cows and the herds were collected by farm survey and Dairy Herd Improvement records. A set of mixed-effect models using all cows and only 2+ parity cows were used to investigate the association between BLV ELISA-corrected optical density and 305-d mature equivalents of individual cows. The BLV milk positivity was associated with decreased 305-d mature-equivalent yields, especially among the older cows. Additionally, increasing milk ELISA-corrected optical density was associated with increasing loss of milk production at the cow level. In summary, our results provide evidence that BLV infection is associated with decreased milk production in Michigan dairy cows.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Lactação
/
Leucose Enzoótica Bovina
/
Vírus da Leucemia Bovina
/
Leite
Limite:
Animals
/
Pregnancy
País/Região como assunto:
America do norte
Idioma:
En
Revista:
J Dairy Sci
Ano de publicação:
2016
Tipo de documento:
Article