Association between exposure to Neospora caninum and milk production in dairy cows.
OBJECTIVE
To determine association between exposure to Neospora caninum and milk production in dairy cows.


METHODS
Prospective observational study.


METHODS
565 Holstein cows.


METHODS
Cows were classified as seropositive or seronegative to N. caninum within 7 days after calving by use of a kinetic ELISA. Milk production was compared between seropositive and seronegative cows.


RESULTS
On the basis of 305-day mature equivalent milk production data, seropositive cows produced less milk (2.8 lb/cow per day) than did seronegative cows. In addition, analysis of results throughout the first 300 days of lactation revealed that after adjusting for effects of lactation number, calving season, clinical mastitis, and lameness, milk weight of seropositive cows was 2.5 lb/cow per day less than that of seronegative cows.


CONCLUSIONS
Exposure to N. caninum was associated with a 3 to 4% decrease in milk production. A decrease in milk production of 800 lb/cow for a typical 305-day lactation represents a loss of $128/cow.
Hernandez
J
J
Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville 32610-0136, USA.
Risco
C
C
Donovan
A
A
D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood*; D002417:Cattle / Q000502:physiology*; D002418:Cattle Diseases / Q000191:economics / Q000503:physiopathology*; D003048:Coccidiosis / Q000191:economics / Q000503:physiopathology / Q000662:veterinary*; D003612:Dairying; D005260:Female; D007774:Lactation; D007775:Lactation Disorders / Q000191:economics / Q000209:etiology / Q000662:veterinary; D008892:Milk / Q000378:metabolism*; D018688:Neospora / Q000276:immunology; D011446:Prospective Studies; D012098:Reproduction
D000913:Antibodies, Protozoan