Vitamins post-calving: a way to increase cow fertility?
A targeted treatment for post-partum infertility in dairy cowsMarc-André Sirard, Rachel Gervais
After calving, dairy cows are less fertile for up to three months, particularly high-yielding cows. Why is this? It could be that a deficiency of vitamins A and D negatively affects fertilization. Herds rarely go out in the spring to feed on pastures rich in vitamins A and D, a situation which is known to affect fertility. According to past studies, a lack of these two substances can lead to an energy deficiency, and genes that depend on vitamin A are abnormally expressed 60 days post-calving. In this new research, professor Marc-André Sirard’s team will examine if cows are more easily fertilized when they take a vitamin A and D supplement between the 50th and 90th day following calving. Forty-eight cows will undergo blood testing to establish their energy profile upon taking a vitamin supplement and will then be inseminated. A similar vitamin supply has already been studied, but never during this key period in the reproduction cycle. The hypothesis is that the ovaries will sense a seasonal effect and that a targeted supplement of vitamins A and D will reproduce the arrival of fresh pasture (vitamin A) in spring (vitamin D) and influence fertility.