Nutrition and Reproduction in Dairy Cattle

Nutrition has an important impact on the reproductive performance of dairy cattle. Energy is the major nutrient required by adult cattle, and inadequate energy intake has a detrimental impact on reproductive activity of the female bovine. Cows under negative energy balance have extended periods of anovulation. Postpartum anestrus, as well as infertility, is magnified by losses of body condition during the early postpartum period. Resumption of ovulatory cycles is associated with energy balance, but it seems to be mediated by a rise in plasma insulin-like growth factor-I (IGF-I), which is linked to nutritional status and concentrations of insulin in blood. Feeding diets that promote higher plasma glucose and insulin may improve the metabolic and endocrine status of cows. Feeding behavior of dairy cows during the transition period, particularly a decline in feed intake prior to calving, is associated with risk of postpartum uterine disease, such as metritis. Because metritis has a profound negative effect on risk of pregnancy in dairy cows, providing adequate bunk space and environment to maximize feed intake is expected to minimize the risk of uterine diseases and improve fertility. Addition of supplemental fat to the diet improves energy intake, modulates prostaglandin F2α (PGF2α) secretion by the uterus, affects ovarian dynamics, enhances luteal function, and improves fertility. More specifically, some fatty acids (FA) might impact fertilization rate and embryo quality in dairy cows. Although gossypol intake seems to not affect lactation performance of dairy cows, it may affect fertility when the resulting plasma gossypol concentrations are excessive.