RESUMO
Commercial gestation housing systems for sows generally fail to cater fully for their needs in terms of comfort or the ability to perform highly motivated behaviours, which can lead to chronic stress and an impairment to welfare. We compared a typical gestation system (CONTROL) with an IMPROVED one as regards oral stereotypies, aggressive behaviour, skin lesions, locomotion, and tear staining. Sows were mixed into 12 stable groups (six groups per treatment, 20 sows per group), 29 days post-service in pens with free-access, full-length individual feeding/lying stalls. CONTROL pens had fully slatted concrete floors, with two blocks of wood and two chains suspended in the group area. IMPROVED pens were the same but with rubber mats and a length of manila rope in each feeding stall, and straw provided in three racks in the group area. Direct observations of oral stereotypical (30 instantaneous scans per sow per day) and aggressive (all-occurrence sampling, 3 h per sow per day) behaviours were conducted 72 h post-mixing, in mid and late gestation. Skin lesions were counted 24 h and three weeks post-mixing, and in late gestation. Sows' locomotion (locomotory ability) was scored using a visual analogue scale in mid and late gestation. Right and left eye tear staining was scored in late gestation. Indications of better welfare in IMPROVED sows included performance of fewer oral stereotypies in mid and late gestation, and lower tear stain scores. These sows performed more aggression in late gestation, which was associated with access to enrichment, but skin lesion counts were not affected. Thus, the changes made in the IMPROVED treatment benefitted aspects of sow welfare.
RESUMO
Prenatal stress is the mechanism through which poor welfare of pregnant sows has detrimental effects on the health and resilience of their piglets. We compared two gestation housing systems (IMPROVED versus [conventional] CONTROL) in terms of sow stress and welfare indicators and sought to determine whether potential benefits to the sows would translate into improved offspring health. Sows were mixed into 12 stable groups (six groups per treatment, 20 sows per group) 29 days post-service in pens with free-access, full-length individual feeding/lying-stalls. CONTROL pens had fully slatted concrete floors, with two blocks of wood and two chains suspended in the group area. IMPROVED pens were the same but with rubber mats and manila rope in each stall, and straw provided in three racks in the group area. Saliva was collected from each sow on day 80 of pregnancy and analysed for haptoglobin. Hair cortisol was measured in late gestation. Sows' right and left eyes were scored for tear staining in mid lactation and at weaning. Numbers of piglets born alive, dead, mummified, and total born were recorded. Piglets were weighed and scored for vitality and intra-uterine growth restriction (IUGR) at birth. Presence of diarrhoea in farrowing pens was scored every second day throughout the suckling period. IMPROVED sows had lower haptoglobin levels and tear-stain scores during lactation. IMPROVED sows produced fewer mummified piglets, and these had significantly lower IUGR scores, and scored lower for diarrhoea than piglets of CONTROL sows. Hence, improving sow welfare during gestation improved the health and performance of their offspring.
