Bacillus subtilisandEnterococcus faeciumco-fermented feed regulates lactating sow's performance, immune status and gut microbiota

Fermented feed (FF) is widely applied to improve swine performance. However, the understandings of the effects of FF on the immune status and gut microbiota of lactating sows and whether probiotics are the effective composition of FF are still limited. The present study aimed to investigate the performance, immune status and gut microbiota of lactating sows fed with a basal diet supplemented withBacillus subtilisandEnterococcus faeciumco-fermented feed (FF), with the probiotic combination (PRO) ofB. subtilisandE. faeciumand control diet (CON) as controls. Compared with the CON group, FF group remarkably improved the average daily feed intake of sows and the weight gain of piglets, while significantly decreased the backfat loss, constipation rate of sows and diarrhoea incidence of piglets. The yield and quality of milk of sows in FF group were improved. Besides, faecal acetate and butyrate were promoted in FF group. Additionally, FF increased the level of IgG, IgM and IL-10 and decreased the concentration of TNF-alpha in serum. Furthermore, FF reduced the abundance ofEnterobacteriaceaeand increased the level ofLactobacillusandSucciniclasticum, which were remarkably associated with growth performance and serum immune parameters. Accordingly, microbial metabolic functions including DNA repair and recombination proteins, glycolysis and gluconeogenesis, mismatch repair andd-alanine metabolism were significantly upregulated, while amino acid metabolism was downregulated in FF group. Overall, the beneficial effects of FF were superior to PRO treatment. Altogether, administration of FF during lactation improved the performance and immune status, and modulated gut microbiota of sows. Probiotics are not the only one effective compound of FF.

Automated summary

The study found that increasing the probiotic content in the feed of lactating sows (FF group) can significantly improve the average daily feed intake of sows and the weight gain of piglets, while significantly reducing the backfat loss, constipation rate of sows, and diarrhea incidence of piglets. Additionally, the milk yield and quality of sows in the FF group were improved, and faecal acetate and butyrate were promoted as well.