Health and performance of young dairy calves vaccinated with a modified-live Mannheimia haemolytica and Pasteurella multocida vaccine.
OBJECTIVE
To evaluate the health and performance of young dairy calves vaccinated with a commercial Mannheimia haemolytica and Pasteurella multocida vaccine.


METHODS
Randomized clinical trial.


METHODS
358 Holstein dairy calves between 14 and 20 days of age on 8 farms.


METHODS
Calves were randomly assigned to a control or vaccinated group. The vaccine used was a commercial modified-live M. haemolytica and P. multocida vaccine that was administered on days 0 and 14. Calf weight was measured on day 0 and monthly for 3 months. Farmers were asked to record any treatment given to the calves and the reason for treatment during the 4 months of the study. Blood was collected from all calves on days 0 and 28, and titers of antibodies to M. haemolytica were determined by means of direct bacterial agglutination.


RESULTS
Mean daily gain was not significantly different between vaccinated and control calves. Vaccinated calves had a significantly greater increase in antibody titers (5.3-fold increase), compared with control calves (3.6-fold increase). There was no significant difference between vaccinated and control calves for any of the treatment outcomes (number and duration of treatments and age at first and last treatments).


CONCLUSIONS
Results suggest that the M. haemolytica and P. multocida vaccine, given twice 2 weeks apart, was effective in increasing titers of antibodies against M. haemolytica in young dairy calves but did not improve calf performance or health.
Aubry
P
P
Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
Warnick
L D
LD
Guard
C L
CL
Hill
B W
BW
Witt
M F
MF
D000818:Animals; D000831:Animals, Newborn; D000907:Antibodies, Bacterial / Q000097:blood; D001428:Bacterial Vaccines / Q000008:administration & dosage; D002417:Cattle; D005260:Female; D016978:Mannheimia haemolytica / Q000276:immunology*; D016979:Pasteurella multocida / Q000276:immunology*; D012766:Pasteurellosis, Pneumonic / Q000276:immunology / Q000517:prevention & control*; D016896:Treatment Outcome; D014611:Vaccination / Q000662:veterinary; D015430:Weight Gain
D000907:Antibodies, Bacterial; D001428:Bacterial Vaccines