Effect of varying energy levels fed during gestation on reproduction
and calf performance were studied in three trials involving 266 first calf
heifers. Reducing energy during mid-gestation did not adversely affect
the performance of the heifers when they were fed properly for at least 50 days before calving. Heifers on restricted levels of energy during
mid-gestation and then elevated tended to have both higher first-service
conception rates and total conception rates. Restricting energy throughout
the gestation period reduced reproductive performance, causing lighter
calves at birth and weaning emphasizing the importance of energy in the
diet of first calf heifers.
