Effects of feeding crude protein on the reproductive performance of females in the first pregnancy

Three treatments were accomplished (10.0, 13.5, and 17.0% of CP) to evaluate the effect of dietary CP levels on the reproductive performance of 36 females (12 females per treatment) in the first pregnancy. The diets were formulated to contain (or to exceed) all the nutrients to meet the animal requirements, with the exception of CP, according to NRC (1998). Although the protein was diluted with starch, the amino acid proportion was constant in all diet, due to the constant relation of the amounts of corn and soy meal. Gilt weight gain during the gestation, number of born pigs, litter weight, backfat thickness and nut performance during the nursing were evaluated. No significant differences among the averages of weight gain during the gestation, backfat thickness, piglet weight at birth and number of born piglets were observed. In the nursing phase, there was no effect of the groups of females fed different dietary CP levels in the gestation on feed intake, weight loss, backfat thickness loss, daily weight gain of the piglets and litter weight at weaning. No treatment effects on weaning-estrus interval and reproductive and productive performances of females in the first pregnancy were observed.

born alive; female weight gain; feed intake; piglet weight at birth