Environmental enrichment for primiparous and multiparous pregnant sows and its effect on cortisol and behavior at farrowing and production parameters at weaning

The study evaluated the effect of environmental enrichment (EE) during gestation of primiparous and multiparous sows on the concentrations of cortisol, behavior at farrowing, and production parameters of sows and their piglets. Primiparous (n = 20) and multiparous (n = 20) sows were included. Half of the sows received EE from Week 6 to Week 14 of gestation, while the remaining sows received no EE. The concentrations of hair cortisol on Weeks 6 and 15 of gestation, the behavior of the sows before, during, and after parturition, and some production parameters of the sows and their piglets at birth and weaning were compared among groups. Cortisol increased from Week 6 through Week 15 in all the sows and it was greater in those with no EE. Before, during, and after parturition the primiparous sows that received EE showed behavioral patterns suggestive of better dealing with stress and pain, in comparison mainly with primiparous sows that received no EE. The number of piglets born alive, the total of piglets born, and the weight at birth by litter were similar (P > 0.05) in all groups. The weight at weaning by litter was greater (P < 0.05) for piglets of primiparous sows with EE and less (P < 0.05) for piglets of primiparous sows with no EE. In conclusion, providing sows, particularly gilts, with EE during gestation reduced their stress and pain during parturition, and improved the weight gain in their piglets.