A note on sows' behaviour towards humans during lactation in farrowing pens with short-term fixation and its effects on piglet mortality

Abstract

The objective of this study was to determine a relationship between sows’ aggressive behaviour towards humans in farrowing pens with space to move freely and its reproductive outcome. A total of 215 crossbred (Large White x Landrace) sows were included in the research. All sows were housed in farrowing pens with movable crates whereby the crate was closed for five days around farrowing. To measure the sows’ behaviour towards a stockperson, the reaction on being separated from her piglets when handled were scored in week 1 and week 4 of lactation in a separation test. Each sow was scored between 1 (not aggressive) and 5 (extremely aggressive). In addition, reproductive performance was documented as piglets born alive, their birth and weaning weight, piglet losses and piglet losses due to crushing. The majority of the sows showed no aggressive behaviour (scores 1 and 2) in both tests (86.7%). However, sows reacted significant more aggressively in week 1 (16.7%) than in week 4 (10.0%; p < 0.05). The sows’ aggression towards the stockperson had a significant influence on piglet losses. Regardless of whether the sows were aggressive only in week 1 or week 4 or at both times, the aggressive sows (scores 3 to 5) lost significantly more piglets than the sows classified as non-aggressive (scores 1 and 2) (20.1% ± 2.83 vs. 14.1% ± 0.89; p < 0.05). Furthermore, aggressive sows tended to crush more piglets compared to non-aggressive sows (8.91% ± 1.98 vs. 5.59% ± 0.63; p = 0.08). These results indicate that aggressive behaviour of sows towards humans cannot be considered equivalent to good maternal behaviour of sows.