Functional effects of Arginine supplementation during gestation and lactation on the productive performance of sow and litter

This thesis reports one meta-analysis and two experimental studies that may contribute to understanding how dietary Arginine (Arg) supplementation during gestation, transition, and lactation, can impact the productive performance of sows and piglets. The meta-analysis showed that dietary Arg should be increased during gestation to maximize the productive performance in terms of placental efficiency, backfat thickness loss, and number of total born and born alive. The second study was set up based on the results of the meta-analysis. Dietary SID Arg:Lys was 216% during different periods of gestation (early, late or all). The results showed a reduction in both the rate of stillbirth and low birth weight piglets if Arg was increased in early gestation, while it reduced the stillbirth rate and increased the percentage of high birth weight piglets in late gestation. However, the increase in dietary Arg through all gestation increased the percentage of low vitality piglets and consequently the percentage of crushed piglets. No differences were observed for the proximal composition of colostrum, except for a significant reduction in the concentration of IgG in all the groups fed a higher dose of Arg. The increase in Arg also modified the metabolome characterization of feces, urine, and colostrum, but no differences for the fecal microbiota were observed. In the third study dietary SID Arg:Lys was 120% during transition and lactation of sows. No differences in farrowing duration, litter characteristics at birth and weaning, colostrum and milk composition, and blood urea nitrogen concentration were observed. According to these results, a higher dose of Arg may be needed to observe significant effects. Overall, the results of these studies underline the role of Arg and its involvement in the metabolic pathways. Furthermore, more studies are needed to evaluate the effects during transition and lactation of sows.