Feeding strategies promoting the health and performance of mother and calf: a winning combination for dairy farms

The transition period from -3 to 3 weeks relative to the parturition is challenging for modern dairy cows as several health problems might occur. For instance, an inadequate precalving diet can exacerbate the state of negative energy balance in early lactation and then favor an excessive body reserve mobilization leading to metabolic diseases. Calves are born almost agammaglobulinemic and they rely on colostrum consumption to get immunoglobulin to fight against potential infectious agents. Other colostral bioactive components ensuring calf health remain to be identified. Early lactation and early life problems for cows and calves, respectively, cause severe monetary loss for dairy producers. This project aims to identify nutritional strategies optimizing colostrum quality and cow and calf health during the peri-partum period in commercial dairy herds. Specifically, B vitamins have important roles in several reactions linked to energy and protein metabolism, DNA methylation and cell growth. It has been shown that supplementation of some B vitamins enhance energy metabolism in early lactation. We hypothesize that certain types of precalving rations, without the use of B-vitamin supplements, optimize B-vitamin status of the dam during the peri-partum period and of the colostrum. Intake of this colostrum by the calves would be beneficial by increasing their B-vitamin supply and possibly by improving epigenetic programmation as vitamin B9 has a role in DNA methylation. Calves do not have a functional rumen at birth and rely on B-vitamin supply to fulfill their requirements. Optimizing dam B-vitamin status around parturition through the precalving diet as well as the calf status would decrease cow and calf health problems and then avoid monetary loss. This project would allow evaluating if B vitamins can be considered as colostral bioactive components favoring calf growth and health. Links between B-vitamin maternal status, colostral immunoglobulin concentrations and epigenetic profile would be done. It is essential to assess nutritional factors influencing colostral immunoglobulin concentration to maximize their concentrations. Recommandations would be done on diet type (ex. percentage of corn silage) or nutritive composition (ex. percentages of fiber and starch) to favor in pre-calving rations to optimize Bvitamin statuses of the cow and the calf and B-vitamin and immunoglobulin concentrations of the colostrum.