Effects of dietary fibre and the provision of a foraging substrate on the welfare of sows in different grouping systems

• Main Author: Stewart, C. L.
• Published: Queen's University Belfast 2008
• Subjects: 636.08
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492327

The aim of this PhD thesis was to investigate the effect of increasing dietary fibre level and the provision of foraging substrates on the welfare of sows housed in dynamic and static groups. To achieve this a review paper was compiled, and three experiments conducted. The aim of the review paper was to assess the effecti,:eness of increasing dietary fibre levels on the welfare of pregnant sows. Previous research found that increasing dietary fibre levels decreased activity levels and the performanc'e of stereotypic behaviour, and increased resting ~ehaviour. However the optimum fibrous ingredient, ,or combination of ingredients, and the optimum dietary inclusion rate for these ingredients remains unclear. The first experimental study assessed the effects of providing sows in large dynamic groups with access to straw in racks. Sows spent almost 10% of their time exploring the straw racks and consequently less time performing general exploratory behaviour. .Increased levels of aggression were observed in the straw treatment, and provision of straw had no effect on sham chewing behaviour. These findings suggest that welfare benefits associated with providing sows in large dynamic groups with access to straw racks are limited. The second experimental study assessed the effect of increasing fibre levels in the concentrate ration (to 15% crude fibre) on the welfare of sows housed in a large dynamic group. This resulted in less stereotypic behaviour and increased time spent resting. It also promoted the use of kennel areas by newly introduced sows to the group, and reduced some aggressive behaviours. Therefore, providing a high fibre diet had a positive effect on the welfare of dry sows housed in a large dynamic group. The third experiment assessed the effect of increasing dietary fibre levels (to 9% crude fibre) and providing straw in racks on the welfare of sows in small static groups. Sows offered the high fibre diet appeared to rest more, and additive benefits, in terms of reductions in stereotypic behaviour, where observed when the high fibre diet was combined with access to straw.