The addition of encapsulated Bacillus subtilis, Enterococcus faecium, and Lactobacillus plantarum postbiotics, either alone or with inulin, improves slaughter weight, gut function, and microbiota in broilers.

Abstract

BACKGROUND: Postbiotics have emerged as innovative feed additives that can replace antibiotics and probiotics. Postbiotics derived from distinct probiotic species may exhibit varying mechanisms of action due to differences in their composition. Moreover, the combined effects of encapsulated postbiotics and inulin on gut function, microbiota composition, and nutrient digestibility in broilers have not been comprehensively investigated. Therefore, this study investigated the effects of supplementing a basal diet with different encapsulated postbiotics, either alone or in combination with inulin, on slaughter and digestive organ weights, small intestinal morphology, cecal microbiota and short-chain fatty acid concentrations, as well as nutrient digestibility in broilers. A total of 588 one-day-old male broiler chicks (Ross 308) with similar initial body weights were randomly assigned to seven dietary treatments. Each treatment included six replicates, with 14 birds per replicate. The experimental diets consisted of a basal diet (C), the basal diet supplemented with 0.3% encapsulated postbiotics derived from Bacillus subtilis (EBS), Enterococcus faecium (EEF), or Lactobacillus plantarum (ELP); and combinations of these encapsulated postbiotics with 1% inulin: EBSI (EBS&#x2009;+&#x2009;inulin), EEFI (EEF&#x2009;+&#x2009;inulin), and ELPI (ELP&#x2009;+&#x2009;inulin), fed for six weeks. RESULTS: Encapsulated various postbiotics and inulin, increased slaughter weight, feed intake and the relative weights of the duodenum and jejunum&#x2009;+&#x2009;ileum compared with the C (P&#x2009;<&#x2009;0.05). In contrast, the relative weights of the proventriculus, gizzard, colon, and cecum were unchanged (P&#x2009;>&#x2009;0.05). Villus height, villus width, crypt depth and villus height/crypt depth in the duodenum, jejunum, and ileum improved with encapsulated postbiotics (P&#x2009;<&#x2009;0.05). Cecal Lactobacillus spp. and acetic, butyric, and propionic acid concentrations increased, while Escherichia coli levels reduced (P&#x2009;<&#x2009;0.05). No significant differences in organic matter, protein, or fat digestibility were found (P&#x2009;>&#x2009;0.05). Moreover, although no significant difference was observed between the groups with and without inulin supplementation, an improvement was noted (P&#x2009;>&#x2009;0.05).&#xa0; CONCLUSIONS: Encapsulated different postbiotics (particularly those derived from Bacillus subtilis and Lactobacillus plantarum), either alone or combined with inulin, positively impacted broiler slaughter weight, gut function, and microbiota. These results support the theory that they could be used as potential feed additives in broiler chickens.