Effects of Lysine Intake During Middle to Late Gestation (Day 30 to 110) on Reproductive Performance, Colostrum Composition, Blood Metabolites and Hormones of Multiparous Sows (Report‪)‬

INTRODUCTION The nutrient supply for mature sows during gestation must satisfy their requirements for maintenance as well as for the development and growth of fetal tissue (NRC, 1998). Maternal nutrition plays a critical role in fetal growth and development as well as postnatal performance and health (Wu et al., 2004; Cerisuelo et al., 2009). In late gestation, fetal growth is at a very rapid rate (Trottier and Johnston, 2001) and mammary development also occurs in preparation for the upcoming lactation. Adequate maternal gain during gestation prevents excessive body weight loss after lactation and delayed returns to estrus (Trottier and Johnston, 2001). However, excessive maternal fat gain during gestation should be avoided because it decreases voluntary feed intake during lactation (Revell et al., 1998). Thus, the objective when feeding gestating sows is to obtain optimal fetal growth while maintaining appropriate maternal protein and fat gain (Ji et al., 2005).