Reproduction is an economically important complex composite trait in sheep. Genetic improvement of composite traits can occur by selection for individual components traits, some combination of individual component traits, or by direct selection for the composite trait. This review discusses the responses of selecting directly for litter weight weaned compared to selection responses for one of i...

Body condition was scored at lambing (BCSL) on 101 mature (4 to 7 yr old) Polypay ewes and related to colostral immunoglobulin G (IgG) concentration and lamb performance. Colostrum samples were collected from each ewe within 12 h of lambing and litters of more than two lambs were reduced to two within 2 h of lambing. Colostral IgG concentrations decreased rapidly with time (b = -3.28; R2 = .213...

Methods: Primiparous (n=181) and multiparous (n=759) sows of Large White and Landrace breeding on a commercial swine farm were assigned at the time of parturition to be either split weaned (n=628) or to serve as controls (n=312). Sows were split weaned by removing the heaviest piglets at 21 days of lactation, leaving five to seven piglets with the sow until full weaning 5, 6, or 7 days later. C...