Maria Villagrasa & Nuria Garcia
A negative energy balance of dairy cows at the beginning of the lactation delays the onset of normal ovarian activity. The energy deficit also alters the hormonal status, the number of estrus cycles is reduced, oocyte quality decreases and embryonic mortality increases. These factors reduce the efficiency of artificial insemination and the success of reproduction.
One strategy to alleviate the negative energy balance is to reduce the energy in milk by supplementing to reduce milk fat synthesis, which could reduce the mobilization of body fat to promote earlier ovulation and better gestation rates.