Association between hoof lesions and fertility of lactating dairy cows

Lameness is an important welfare issue and a serious challenge in the dairy industry. Prevalence of lameness worldwide range from 8 to 55% and is influenced by genetics, housing type, and herd management. Lame cows have reduced fertility and hoof lesions (HL) are responsible for over 90% of lameness. Hoof lesions can be non-infectious such as sole ulcer, toe ulcer, white line disease, sole hemorrhage, or infectious digital dermatitis and foot rot. Association between HL and fertility is scarce. Furthermore, information about the association between stage of HL development and fertility in dairy cows is limited. Our objective was to evaluate the association between HL and ovarian cyclicity, and pregnancy in dairy cows. Our hypotheses were that cows with pre-existing HL during early lactation have delayed resumption of ovulation post-partum, longer interval to first service and to pregnancy, and smaller pregnancy hazard. Also, cows that develop new HL have longer interval to pregnancy and smaller pregnancy hazard.