Reproductive parameters were evaluated in 5,480 Holstein herds involving
335,673 cows to determine the reported negative genetic effect of production on
reproduction. While higher producing herds had a slight decline in days to first
bred, this effect was offset by a similar increase in services per conception. The
greatest effect was seen in the percent of cows open and the average days open.
It was concluded that managers of higher producing herds are more aware of the
need to get cows bred back after calving and implement the necessary practices to
minimize the percent of cows not yet serviced and the average days open. The
negative genetic relationship between production and reproduction may be
overcome with sound management practices.
