TY - JOUR
T1 - Neospora caninum serostatus and milk production of Holstein cattle
AU - Hobson, Jamie C.
AU - Duffield, Todd F.
AU - Kelton, David
AU - Lissemore, Kerry
AU - Hietala, Sharon K.
AU - Leslie, Ken E.
AU - McEwen, Beverly
AU - Cramer, Gerard
AU - Peregrine, Andrew S.
PY - 2002/10/15
Y1 - 2002/10/15
N2 - Objective - To determine whether Neospora canmum serostatus was associated with milk production among Holstein cattle in Ontario. Design - Case-control study and cross-sectional observational study. Animals - 3,702 Holstein cows in 83 herds (case-control study) and 3,162 Holstein cows in 57 herds. Procedure - Herds in the case-control study were grouped on the basis of N caninum abortion status. Herds in the observational study were considered representative of Ontario dairy herds. The N caninum serostatus of individual cows was determined with a kinetic ELISA. Milk production was modeled to compare seropositive with seronegative animals while controlling for parity, days since parturition, and herd clustering. Results - In the case-control study, 305-day milk production of seropositive cows was significantly less than milk production of seronegative cows in herds with abortions attributable to N caninum infection and in herds with abortions attributable to pathogens other than N caninum, but not in herds without abortion problems. In the observational study, 305-day milk production for seropositive cows was not significantly different from milk production of seronegative cows. Conclusions and Clinical Relevance - Results suggest that the association between N caninum serostatus and milk production in Ontario Holstein dairy cattle may depend on abortion status of the herd. In herds with abortion problems, regardless of cause, N caninum-seropositive cattle produced less milk, whereas in herds without abortion problems, N can/num-seropositive cattle produced the same amount of milk as seronegative cattle.
AB - Objective - To determine whether Neospora canmum serostatus was associated with milk production among Holstein cattle in Ontario. Design - Case-control study and cross-sectional observational study. Animals - 3,702 Holstein cows in 83 herds (case-control study) and 3,162 Holstein cows in 57 herds. Procedure - Herds in the case-control study were grouped on the basis of N caninum abortion status. Herds in the observational study were considered representative of Ontario dairy herds. The N caninum serostatus of individual cows was determined with a kinetic ELISA. Milk production was modeled to compare seropositive with seronegative animals while controlling for parity, days since parturition, and herd clustering. Results - In the case-control study, 305-day milk production of seropositive cows was significantly less than milk production of seronegative cows in herds with abortions attributable to N caninum infection and in herds with abortions attributable to pathogens other than N caninum, but not in herds without abortion problems. In the observational study, 305-day milk production for seropositive cows was not significantly different from milk production of seronegative cows. Conclusions and Clinical Relevance - Results suggest that the association between N caninum serostatus and milk production in Ontario Holstein dairy cattle may depend on abortion status of the herd. In herds with abortion problems, regardless of cause, N caninum-seropositive cattle produced less milk, whereas in herds without abortion problems, N can/num-seropositive cattle produced the same amount of milk as seronegative cattle.
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U2 - 10.2460/javma.2002.221.1160
DO - 10.2460/javma.2002.221.1160
M3 - Article
C2 - 12387387
AN - SCOPUS:0037107652
SN - 0003-1488
VL - 221
SP - 1160
EP - 1164
JO - Journal of the American Veterinary Medical Association
JF - Journal of the American Veterinary Medical Association
IS - 8
ER -