Peri-partum posture and behaviour of gilts and the location of their piglets in lines selected for components of efficient lean growth

Abstract

The proportions of time that gilts expressed defined posture and behaviour traits and the locations of their piglets were determined from video recordings of observations made at 5 min intervals in the period extending from 2 hr pre-farrowing to 2 hr post-farrowing. The 137 gilts studied were from four pairs of Large White lines which had responded to divergent (high and low) selection for either daily food intake (DFI), lean food conversion efficiency (LFC), lean growth rate on ad libitum feeding (LGA) or lean growth rate on restricted feeding (LGS).
Almost all the significant (P<.05) changes occurred in the LGS pair of lines. In the pre-farrowing period, relative to the low LGS gilts, high LGS gilts spent more time lying on their sides (0.92 v. 0.69), and less time in the upright postures of standing, sitting or lying on their bellies (0.08 v. 0.33) and engaging in nesting behaviour (0.02 v. 0.10). During farrowing high LGS gilts again lay on their sides more often than low LGS gilts (0.96 v. 0.80) and were upright less often (0.04 v. 0.20). High LGS gilts changed posture less often than low LGS gilts (0.05 v. 0.31) but were more alert (0.79 v. 0.61). High LGS piglets were seen less at their mother's head, back and vulva or at the creep than low LGS piglets (0.06 v. 0.15). There were no differences between lines post-farrowing, almost all gilts lying on their sides with their piglets at the udder. Divergent selection for components of efficient lean growth rate on ad libitum feeding was not associated with changes in gilt behaviour and posture or in piglet location but selection for high lean growth on restricted feeding appeared to reduce the gilt’s physical activity around farrowing with possible benefits for her welfare and that of her piglets.