Intensive genetic selection over the last two decades has produced major advances in both litter size and birth weight in swine. However, double-digit preweaning mortality rates have limited maximum reproductive performance.

New research funded by the U.S. Department of Agriculture’s Cooperative State Research, Education and Extension Service (CREES) suggests this problem may be corrected by dietary adjustments during sow gestation.

Limit feeding sows during gestation may curtail excessive weight gain, reduce farrowing difficulties and curb appetite during lactation.

But research from a team of scientists at Texas A&M University and Texas Tech University indicate that sows may not receive adequate nutrients during mid- to late-gestation to support complete growth of fetuses and mammary tissues. These nutrients include arginine, one of the amino acids that are the building blocks for tissue proteins.

With funds from the CREES National Research Initiative, researchers Guoyao Wu, Sung Woo Kim and colleagues discovered that preweaning mortality could be greatly reduced by supplementing sow diets with 0.83% arginine between Days 30 and 114 of gestation.

In recent trials, additional arginine boosted the number and total litter weight of piglets born alive by 2 pigs/litter and 24%, respectively.

This study suggests that a specific dietary intervention can enhance reproductive performance in pigs and potentially provide a significant economic return to pork producers.