Enhancing piglet survival and welfare in different farrowing systems

Abstract

Piglet mortality is an animal welfare problem with great economic importance. This study investigated housing and nutritional strategies to improve sow welfare whilst safeguarding the survival of new-born piglets and their welfare and performance from birth to the post weaning period. The first experiment compared the effect of different space allowances in a loose farrowing pen on sow behaviour and piglet survival. The behaviours of sows which lead to crushing of piglets, the main reason for mortality, differed between the two pen sizes. A second experiment examined the effect of maternal diet supplementation in late gestation and lactation with docosaheaxanoic acid (DHA) on piglet survival and growth in crated or loose farrowing systems. Performance did not differ between systems. DHA supplementation resulted in fewer stillborn piglets, despite prolonged farrowing duration. Sows given DHA had more vital piglets, with reduced latency to stand, to get to the teat and suckle, but also had reduced weaning weight. A detailed study to investigate the mechanisms underlying this finding measured the behavioural and physiological characteristics of new born piglets. The same effects of DHA on the farrowing process and piglet vitality were apparent, but could not be explained by differences in blood lactate, glucose or thermoregulation of piglets in the perinatal period. A final experiment investigated a new approach to try and improve weaning weight, by stimulating foraging behaviour through sequential presentation of creep feeds differing in flavour. This treatment increased creep feed consumption in both crate and loose housing systems, with a beneficial effect on post weaning growth. The thesis demonstrates ways in which piglet survival and growth can be enhanced by appropriate pen design and nutritional strategies in both conventional and alternative farrowing systems.