Long-term performance and behavior of sows fed high levels of non-starch polysaccharides

The main objective of this thesis was to investigate the long-term effects of feeding sows high levels of dietary fermentable non-starch polysaccharides CNSP) (i.e., NSP from sugar beet pulp) restrictedly or ad libitum during gestation or ad libitum during lactation on behavior, reproductive performance, and development in body weight and backfat thickness. During gestation, sows were group-housed. Feeding gestating sows a high level of dietary fermentable NSP restrictedly reduced the frequency of total non-feeding oral activities in gestation compared with a starch diet. Feeding sows a high level of dietary fermentable NSP during lactation reduced the frequency of total non-feeding oral activities during subsequent gestation compared with a starch diet. Body weight and backfat gains during gestation were lower in sows fed a high level of dietary fermentable NSP restrictedly during gestation over three successive parities than in sows fed a starch diet restrictedly. These results indicate an overestimation of the energy value of fermentable NSP. Body weight and backfat losses during lactation were less in sows fed a high level of dietary fermentable NSP during gestation than in sows fed a starch diet. Sows fed a high level of dietary fermentable NSP during lactation lost more backfat during lactation than sows fed a starch diet. The number of live born piglets was 0.5 piglet higher in sows fed a high level of dietary fermentable NSP from weaning until mating and during subsequent gestation than in sows fed a starch diet. It may be that this effect can be attributed to feeding sows a high level of dietary fermentable NSP from weaning until mating. Lactation diet did not affect the number of live born piglets in the following parity. Gestating sows that were fed a high level of dietary fermentable NSP ad libitum during three successive parities ate 1.3 kg/d more during gestation than sows that were fed a starch diet restrictedly (4.2 versus 2.9 kg/d), resulting in higher body weight and backfat gains during gestation and greater losses in body weight and backfat during lactation. Feed intake during lactation was similar in sows that were fed restrictedly or ad libitum during gestation. Reproductive performance was not affected by feeding gestating sows a high level of dietary fermentable NSP ad libitum. Ad libitum fed sows spent 90 min/d eating whereas restrictedly fed sows spent 24 min/d eating. An increase in time spent eating is associated with a reduction in feeding motivation and in stereotypic behaviors. In conclusion, feeding gestating sows a high level of dietary fermentable NSP reduces the level of stereotypic behavior in gestation compared to a starch diet. Feeding sows a diet with a high level of fermentable NSP during lactation has an additional reducing effect on the development of stereotypic behavior in subsequent gestation. Reproductive performance is not negatively affected by feeding gestating sows a diet with a high level of fermentable NSP (i.e. NSP from sugar beet puIp) restrictediy or ad libitum during three successive parities compared to feeding gestating sows a starch diet restrictedly.