The effects of a growth-altering pre-pubertal feeding regimen on mammary development and parity-one lactation potential in swine

Abstract

Two-hundred and fifty-four crossbred gilts were allotted to ‘moderate’ or ‘control’ growth regimens from 9 to 25 weeks of age. The moderate regimen used dietary fiber to achieve alternating phases of moderate and maximum growth during four distinct pre-pubertal periods. High-fiber diets, containing 35% ground sunflower hulls, were fed during periods one and three (3 and 5 weeks, respectively) to slow growth. During periods two and four, low-fiber corn–soybean meal (CSBM)-based diets were fed for 3 and 5 weeks, respectively, to maximize growth. Control gilts were fed CSBM-based diets in all periods to maximize growth. Ad-libitum access to feed was allowed at all times with both regimens. After 25 weeks of age, both treatment groups were managed similarly. Analysis of mammary tissue collected on day 110 of gestation revealed that moderate gilts had less ( P=0.03) parenchymal tissue, and tended to have less ( P=0.09) total DNA than control gilts. However, during lactation moderate females consumed more feed ( P=0.02) and tended ( P=0.07) to wean heavier litters. Altering gilt growth before puberty enhanced sow lactation performance despite decreasing pre-lactation mammary development.