Effects of postbiotics substitute for acidifiers on growth performance,nutrient apparent digestibility,fecal microorganism,and immune indexes of weaned piglets

WU Fei; WU Zhiwei; LIU Hu; HAN Jie; XU Xuexin; WANG Lu

doi:10.13557/j.cnki.issn1002-2813.2025.07.006

Abstract：The experiment aims to investigate the effects of dietary postbiotics levels substituted for acidifiers on the growth performance,nutrient apparent digestibility,fecal microorganism,and immune indexes of weaned piglets.A total of 192 weaned piglets of the three-way hybrid with a weight of(7.64±0.58)kg at 28 days of age were selected and randomly divided into four groups,with six replicates in each group and eight pigs in each replicate.The control group was fed a basal diet without antibiotics,the acidifier group was fed a basal diet supplemented with 0.50%benzoic acid,the postbiotics low concentration group was fed with a basal diet supplemented with 0.25%postbiotics,the postbiotics high concentration group was fed with a basal diet supplemented with 0.50%postbiotics.The pre-test lasted for seven days and the formal test lasted for 28 days.The results showed that compared with the control group,the average daily gain in the postbiotics high concentration group was significantly increased(P<0.05),the ratio of feed to gain and diarrhea rate were significantly decreased(P<0.05),and the diarrhea rate in the postbiotics high concentration group was significantly lower than that in the acidifier group(P<0.05).Compared with control group,the apparent digestibility of dry matter,crude protein,crude fat,crude fiber,calcium,and phosphorus in postbiotics high concentration group were significantly increased(P<0.05).Compared with acidifier group,the apparent digestibility of dry matter,crude fat,crude fiber,and calcium in postbiotics high concentration group were significantly increased(P<0.05).Compared with the control group,the ratio of Lactobacillus to Escherichia coli in postbiotics group was significantly increased(P<0.05),and the number of Escherichia coli was significantly decreased(P<0.05).Compared with acidifier group,the number of Escherichia coli in postbiotics group was significantly decreased(P<0.05),and the ratio of Lactobacillus to Escherichia coli was significantly increased(P<0.05).Compared with control group,the concentrations of immunoglobulin and inflammatory factors in postbiotics group were significantly decreased(P<0.05).Compared with acidifier group,the concentrations of immunoglobulin G,immunoglobulin M,interleukin-6 and tumor necrosis factor-α in postbiotics group were significantly decreased(P<0.05).The study indicates that the addition of postbiotics to antibiotic-free diets can enhance the growth performance of weaned piglets,improve nutrient apparent digestibility and fecal microbiota composition,while reducing immunoglobulin and pro-inflammatory cytokine levels,supplementing 0.25%postbiotics achieves comparable feeding effects to 0.50%benzoic acid.