Sows’ pre- and post-crate opening behaviour in farrowing pens with different opening times

Abstract

The aim of the present study was to investigate the sows’ behaviour in farrowing pens with a short-term fixation of five days around birth and the influence of the reproductive outcome. It was hypothesised that opening the farrowing crate in the evening may result in calmer sows due to less disturbance by stockpersons and thereby fewer dangerous posture changes of the sow and fewer piglet losses. The study focused on the pre- and post-crate opening behaviour of the sows expressed in lying down and rolling behaviour. Farrowing crates were opened three days post partum in the morning at 06.00 am (AM: n = 16) or in the evening at 06.00 pm (PM: n = 16). A further division was undertaken for sows with low (LR: n = 16) and high (HR: n = 16) rolling behaviour in the post-opening period. Video sequences of 72 h, divided into 24 h before and 48 h after the farrowing crate was opened were recorded continuously (to observe behaviour) and analysed using two event sampling methods: The frequencies of the lying down and rolling behaviour of the sows were documented as point events while the sows’ time budget (standing, sitting, lying) and the piglets’ positions during the sows’ lying down and rolling were documented as state events. The results show that rolling behaviour was performed less when the crate was opened in the evening compared to opening the crate in the morning (p = 0.08). Crushed piglets during lactation did not differ significantly between the groups but this tended to occur less frequently for PM grouped sows in the post-opening period. HR sows performed rolling more than twice as often as LR sows (p < 0.05) and showed significantly more frequent rolling from belly to side (p < 0.05). Furthermore, no significant difference was found for crushed piglets during lactation and both LR sows and HR sows crushed a similar number of piglets in the post-opening period. In both groups (AM, PM respectively LR, HR) the piglets’ positions were in the nest in more than 50% of the rolling events. In conclusion, crate opening in the evening resulted in less rolling movements, sows in the PM group tended to crush fewer piglets in the post-opening period compared to sows in the AM group. Opening the crate in the evening seems to be better, with the advantage that the animals are calmer and show less postural change due to an undisturbed environment after opening.