Effects of Lactobacillus plantarum Postbiotics on Growth Performance, Immune Status, and Intestinal Microflora of Growing Minks

SIMPLE SUMMARY: The wet diet that minks have, due to its high moisture content, is prone to breeding harmful microorganisms in hot weather, resulting in severe diarrhea for minks. It has been proposed that probiotics can inhibit the intestinal colonization of pathogens that cause diarrhea. Probiotics as live microorganisms are beneficial in helping protect from chronic inflammatory bowel disease, improving intestinal flora structure and host immune function. However, it is not very convenient to maintain high viability of bacteria during processing, storage, and transportation of feeds with probiotics. Many studies have shown that inactivated probiotics and their metabolites also provide benefits for host health. These inactivated probiotics and their metabolites, known as postbiotics, have been accepted for their high safety and stability, easy storage and production, and long shelf life. This study proved that Lactobacillus plantarum postbiotics have biological effects on growing minks. ABSTRACT: The present experiment was conducted to investigate the effects of Lactobacillus plantarum postbiotics on growth performance, immune status, and intestinal microflora of growing minks. A total of 80 minks (40 males and 40 females) were divided into four groups, each group contained 20 minks (10 males and 10 females). The minks in the four groups were fed a basal diet supplemented with 0, 0.15%, 0.3%, and 0.45% Lactobacillus plantarum postbiotics (PLP), respectively. After one week of adaptation, the experiment ran for eight weeks. The results showed that Lactobacillus plantarum postbiotics tended to have effects on average daily again (ADG) during the first 4 wk of the study (p < 0.1), and had effects on immune status (p < 0.05). Lactobacillus plantarum postbiotics also affected the abundance of intestinal bacteria at genus level (p < 0.05), but had no effects on α diversity of growing minks (p > 0.05). Compared to the minks in the control group, minks in 0.30% PLP group tended to have greater ADG, and IgA and IgM content in serum as well as SIgA content in jejunal mucosa (p < 0.05), and had less jejunal mucosal TNF-α and IL-8 levels, while minks in 0.45% PLP group had less IL-2 (p < 0.05). Compared to the control, Lactobacillus plantarum postbiotics decreased the relative abundances of Bacteroides_vulgatus and Luteimonas_sp. in male minks, and the relative abundances of Streptococcus_halotolerans in female minks (p < 0.05), respectively. Males grew faster and ate more associated with less F/G than females (p < 0.05). Males also had greater serum IgA and IgG content (p < 0.05), and males had less jejunal mucosal IL-1β, IL-8, IL-2, IL-6, IL-12, IL-10, TNF-α, and IFN-γ levels (p < 0.05). These results suggest that dietary supplementation of 0.3% postbiotics harvested from Lactobacillus plantarum could improve growth performance and immune status, and modulated the intestinal bacteria abundance of growing minks.