Productive effects of a colostrum-oriented amino acid dietary supply for sows in transition from gestation to lactation

In sows, the synthesis of the colostrum begins several days before farrowing and the different amino acid composition of colostrum compared to milk can justify the hypothesis of different dietary requirements to produce it. The objective of the study was to test the enrichment with threonine (Thr), tryptophan (Trp) and valine in the peripartum diet of sows on the quality of colostrum, health and growth of piglets, and the variations of backfat and lean thickness and the faecal microbiome of sows. Ninety-nine sows were divided into two groups, balanced by parity number and fed: (1) the standard formula used on late gestation to early lactation (CON; 50 sows; (2) CON added with 0.074% L-Thr, 0.034% L-Trp and 0.077% L-valine (TRT; 49 sows). The number of pigs born alive and their average live weight, the number of weaned pigs, their growth and the mortality on d1 did not change with the diet, but the percentage of total dead piglets was reduced when sows were fed TRT (−3.5%, p =.049). Backfat loss of sows in lactation was marginally reduced (p =.097). The IgA content of colostrum increased with TRT, but not protein, fat, lactose or urea. Bacterial richness (Chao1) decreased in faeces of sows at the end of lactation with TRT, but not bacterial diversity. Selenomonas and Bacillus were more abundant in CON and TRT, respectively. Adjusting the amino acid profile of the feed provided in the transition phase between final gestation and early lactation to the colostrum profile could improve the survival of suckled piglets.Highlights The amino acid profile of colostrum differs from that of milk. The pre-weaning mortality can be decreased by feeding sows a diet with an amino acid profile closer to that of colostrum. Raising the dietary ratio of threonine (Thr), tryptophan (Trp) and valine to lysine (Lys) in the peripartum diet of sows improves the IgA content of colostrum.