Straw vs. peat as nest-building material - The impact on farrowing duration and piglet mortality in loose-housed sows

Abstract

Provision of nest-building material pre-partum is required by farm animal legislation in Norway, but as some farmers have problems with straw in the slurry system, alternative and finer-grained substrates could be of interest. The aim of the present study was to examine the effects of providing different nest-building materials before farrowing (peat and long-stemmed straw) on farrowing duration and piglet mortality. Sows of Norsvin Landrace x Swedish Yorkshire were loose-housed in individual farrowing pens with their litter throughout the entire lactation period, and provided with peat (n=18), long-stemmed straw (n=17), or controls (n=18), fromtwodaysbeforeexpectedfarrowing untilfarrowing. Parityrangedfrom1to 9(mean ± SE:2.9 ± 2.0),of which 16 were gilts. The farrowing was video recorded, and the farrowing duration registered from first to last piglet born. Dead piglets were subjected to a post mortem. Sows provided with long-stemmed straw pre-partum had shorter farrowing duration compared to sows provided with peat or controls (P < 0.001). The percentage of stillborn piglets was also lowest among sows in the straw group compared to the other two groups (P < 0.001). Sows of parity ≥4 had longer farrowing duration than gilts and sows of parity 2–3( P < 0.001). Farrowing duration (P < 0.001) and the percentage of stillbornpigletsincreased(P<0.001)withanincreasingnumberoftotalbornpiglets.Moreover,increasedlitter size resulted in a higher pre-weaning mortality (P=0.016). The present study shows that provision of nest-building material before farrowing is important for the birth process of the sow as it reduces farrowing duration and percentage of stillborn piglets compared to controls without relevant substrate. Although peat gave better results than the control treatment, our results suggest that long-stemmed straw is a more appropriate nest-building material.