Effect of rubber slat mats on the behaviour and welfare of group housed pregnant sows
Publication Type: |
Journal Article |
Year of Publication: |
2014 |
Authors: |
Julia Adriana Calderón Díaz, Laura Ann Boyle |
Publication/Journal: |
Applied Animal Behaviour Science |
Keywords: |
postural behaviour, rubber mats, sows, spatial behaviour, welfare |
ISBN: |
0168-1591 |
Abstract:
This study evaluated the effect of flooring, lameness, body and limb lesion scores on postural and spatial behaviour of gestating sows. Sixty-four sows were kept in groups of four in pens with four solid concrete floored feeding stalls and a concrete fully slatted group area from 4 weeks after service. The slats were either left uncovered (CON; n = 8 groups) or 10 mm thick rubber slat mats were affixed (RUB; n = 8 groups). Lameness (0 = normal to 5 = severe), limb (environmentally induced lesions, e.g. callus, wounds, swellings; scored according to severity—0 = normal to 6 = severe) and body (aggression induced lesions; scored according to severity—0 = normal to 5 = severe) lesions were scored on days 1, 8, 25, 50 and 75 relative to entering the experiment. Additionally video recordings were made of the groups for 24 h on the same days which were sampled instantaneously every 10 min. An index of the proportion of time spent in (1) different postures (standing, ventral [VL] and lateral lying [LL] and total lying [VL + LL]); (2) locations (stalls or group area), (3) posture by location and (4) number of postural changes was calculated. Sows were categorized as non-lame (score ≤1) or lame (score ≥2). Median scores were calculated for body and limb lesions and were classified as ≤median or >median. Lameness, limb and body lesions were analysed using logistic binomial regression. Behavioural variables were tested for normality and analysed using mixed model equations. Flooring did not affect lameness, body lesion scores, time spent in each posture or the index of postural changes (P > 0.05). RUB sows spent more time in the group area (76.3 vs. 53.3 ± 5.8%; P < 0.01) and lay more there (80.0 vs. 62.4 ± 5.3%; P < 0.05) compared with CON sows. Sows with scores >median for wounds on the limbs spent more time LL (41.2 vs. 48.3 ± 3.6%; P < 0.05) and less time VL (36.3 vs. 29.9 ± 2.9%; P < 0.05). On the other hand, sows with body lesion scores >median spent more time VL (29.9 vs. 36.3 ± 2.9%; P < 0.05). Lame sows stood less and lay more (P < 0.05) in the feeding stalls. When sows had access to rubber flooring they spent more time in the covered area and lay more there compared with sows in pens where the concrete slats were bare. This reflects the preference of group housed sows for a comfortable surface for lying during pregnancy. Other sow factors such as body and limb lesions and lameness status are also related with lying behaviour.