Reproductive Performance and Progeny Development in Swine as Influenced by Feed Intake During Pregnancy

Abstract

First-litter gilts (nearly equal numbers of purebred Hampshires, purebred Yorkshires and crossbreds) were used to study effects of gestation-diet intake on reproductive performance and progeny development. From breeding to farrowing, gilts were fed 0.9, 1.4, 1.9, 2.4 or 3.0 kg/day of a diet which was designed to be adequate to superadequate in all nutrients when fed at 1.9 kg. All gilts received this diet ad libitum during a 3-week lactation period. Farrowing percentage (number farrowing as a percentage of those mated) was less for gilts fed 0.9 kg/day than for those fed more, and was less for purebreds than for crossbreds. Gestation-diet intake did not affect the number of pigs farrowed (total or live) or weaned, but crossbreds farrowed and weaned more pigs than purebreds. Birth weight and weaning weight of offspring increased as gestation-diet intake increased; birth weight plateauing at 1.9 kg and weaning weight plateauing at 2.4 kg. As gestation-diet intake increased, weight gain of gilts increased quadratically during gestation but decreased linearly during lactation. Birth weight per pig decreased 43 g for each additional pig in the litter.