Effects of dietary supplementation of Enterococcus faecium postbiotics on growth performance and intestinal health of growing male mink

Recent studies have demonstrated that postbiotics possess bioactivities comparable to those of probiotics. Therefore, our experiment aimed to evaluate the effects of postbiotics derived from Enterococcus faecium on the growth performance and intestinal health of growing male minks. A total of 120 growing male minks were randomly assigned to 4 groups, each with 15 replicates of 2 minks. The minks in the 4 groups were fed a basal diet supplemented with 0 (control), 0.05, 0.1, and 0.15% postbiotics derived from E. faecium (PEF), respectively. Compared to the control, PEF improved feed/gain (F/G) during the first 4 weeks and the entire 8 weeks of the study ( p < 0.05); in addition, 0.1% PEF improved average daily gain (ADG) during the first 4 weeks and the entire 8 weeks of the study ( p < 0.05), while 0.15% PEF improved ADG during the first 4 weeks of the study ( p < 0.05). Consequently, 0.1% PEF minks displayed greater body weight (BW) at weeks 4 and 8 ( p < 0.05), and 0.15% PEF minks had greater BW at week 4 ( p < 0.05) than minks in the control. Furthermore, compared to the control, both 0.05 and 0.1% PEF enhanced the apparent digestibility of crude protein (CP) and ether extract (EE) ( p < 0.05) in the initial 4 weeks, while both 0.1 and 0.15% PEF enhanced the apparent digestibility of CP and DM in the final 4 weeks ( p < 0.05). Additionally, trypsin activity was elevated in the 0.1 and 0.15% PEF groups compared to the control ( p < 0.05). In terms of intestinal morphology, PEF increased the villus height and villus/crypt (V/C) in the jejunum ( p < 0.05), and both 0.1 and 0.15% PEF decreased the crypt depth and increased the villus height and V/C in the duodenum ( p < 0.05) compared to the control group. Supplementation with 0.1% PEF increased the SIgA levels but decreased the IL-2, IL-8, and TNF-α levels in the jejunum ( p < 0.05). Compared to the control, E. faecium postbiotics decreased the relative abundances of Serratia and Fusobacterium ( p < 0.05). In conclusion, the results indicate that the growth performance, digestibility, immunity, and intestine development of minks are considerably affected by E. faecium postbiotics. In particular, dietary supplementation with 0.1% E. faecium postbiotics provides greater benefits than supplementation with 0.05 and 0.15%.