The effect of lameness on the fertility of dairy cattle in a seasonally breeding pasture-based system.
The effect of lameness on the fertility of dairy cattle is well recognized. But, the effect of lameness on the fertility of seasonally breeding cattle in pasture-based systems is less well characterized. This prospective cohort study of 463 cows on 1 farm in the lower North Island of New Zealand was designed to assess the effect of clinical lameness, as identified by farm staff, on the hazard of conception after the planned start-of-mating date. A Cox proportional hazards model with time-varying covariates was used. After controlling for the effect of parity, breed, body weight at calving, and calving-to-planned start of mating interval, the daily hazard of conception for cows identified as lame was 0.78 (95% confidence interval: 0.68-0.86) compared with non-lame cows. Lame cows took 12 d longer to get pregnant compared with their non-lame counterparts.
Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand.
J I
JI
Alawneh
R A
RA
Laven
M A
MA
Stevenson
D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000473:pathology*; D015331:Cohort Studies; D003612:Dairying; D005260:Female; D005298:Fertility / Q000502:physiology*; D007246:Infertility / Q000150:complications / Q000662:veterinary*; D007794:Lameness, Animal / Q000150:complications* / Q000473:pathology; D011247:Pregnancy; D016016:Proportional Hazards Models