Effects of journey duration and temperature during pre-slaughter transport on behaviour of cull sows in lairage.

This observational field study investigated the effects of journey duration, temperature, and waiting duration before unloading on the behaviour of 562 cull sows during lairage from 23 commercial loads. Each load consisted of sows originating from more than one herd, thus experiencing variable pre-slaughter transport and management. In lairage, sows were mixed in groups of 25, involving animals from all journey durations (min-max: 0.8-8.4 h) and video monitored for 60 min. At first most sows were in upright position (approximately 80-90%), decreasing to 30-40% after 30 min. After 60 min, 42% of the sows had initiated aggression (min-max: 0-43 events/sow), 28% had been subjected to aggressive behaviour (min-max: 0-14 events/sow), and 36% s were observed drinking (min-max: 0-16 events/sow). Several significant interactions were found between journey duration, the average temperature in the vehicle and lairage pen (averages: 4.3-26.2 °C) and waiting duration before unloading (min-max: 3-25 min). For example, after short journeys, sows exposed to higher temperature carried out more aggressive behaviour, while a higher temperature after long journeys was associated with more lying and less drinking. This suggests that the sows prioritised lying behaviour over drinking and establishing a dominance hierarchy. We discuss how the results may be interpreted as behavioural signs of fatigue, but further studies, for example involving quantification of physiological and motivational indicators, are needed to clarify this. Irrespectively, the present findings suggest that a stay in a lairage pen, as part of the pre-slaughter logistic chain, involves challenges for the welfare of the cull sows.

Changes in piglet and litter characteristics across parities in two highly prolific sow hybrids in an outdoor organic herd.

High piglet mortality constitutes a welfare challenge in organic pig production. Litter characteristics were investigated from parities 1-5 of two hyper-prolific hybrids with different selection traits in an organic commercial herd (DanBred vs. Topigs Norsvin [TN70]). TN70 sows had more functional teats than DanBred sows, and their offspring had higher birth weights. Several interactions between hybrid and parity were found. The total born increased with higher parity and was more pronounced for DanBred sows. Litter weight at weaning was higher in parities 1-4 for TN70 compared with DanBred, and within DanBred parities 4 and 5 had higher litter weight at weaning than parity 1. The survival rate was higher for TN70 in parities 1 and 2 compared with DanBred, and for both hybrids, the survival rate was higher in parities 1 and 2 compared with parities 4 and 5. The number of weaned piglets was stable across parities 1-4 but lower in parity 5 for both hybrids. Thus, despite a lower number of total born piglets in TN70, TN70 sows weaned the same number of piglets as DanBred, with a lower mortality rate and a heavier litter at weaning.