Optimal voluntary waiting period for highly productive cows in herds of more than 3000 milking heads

Abstract

The study showed that fertility at the first artificial insemination (AI) is 9% higher if the voluntary waiting period (VWP) is 80 days compared to 60 days. However, in the second IO, the level of fertilization in both cases remains the same and is 44%.Thus, the period of voluntary waiting for 80 days of milking provides 80% of the pregnant in our herd on the 150th day of milking, which is an excellent indicator.