Effects of montmorillonite on the growth performance, immunity, intestinal morphology and caecal microflora of broilers.

Context: Montmorillonite (MMT), as a potential antibiotic alternative, has rarely been reported in broiler chickens. Aims: The present study was conducted to determine the effects of dietary MMT supplementation on the growth performance, immunity, intestinal microflora and morphological features of broilers. Methods: One-day-old male broilers (Arbor Acres; n = 240) were randomly assigned to the following four groups before a 42-day feeding trial: (i) basal diet with no supplementation (control group); (ii) basal diet supplemented with 0.1% MMT; (iii) basal diet supplemented with 0.2% MMT; and (iv) basal diet supplemented with 0.3% MMT. Key results: The results demonstrated that supplementation with 0.1% and 0.2% MMT markedly improved the average daily gain of broilers compared with the control group. Moreover, supplementation with 0.1% MMT remarkably decreased the total viable count of Escherichia coli in the caecum of broilers. Compared with the control group, 0.1% MMT supplementation significantly elevated the concentrations of secretory immunoglobulin A and systemic immunoglobulin G in the jejunal mucosa of broilers (P < 0.05). Furthermore, MMT supplementation was associated with a greater villus height (VH) and a higher ratio of VH to crypt depth (CD) in the intestinal mucosa of broilers (P < 0.05). However, in the duodenal and jejunal mucosa, dietary supplementation with MMT exhibited no significant (P > 0.05) impact on the CD values of broilers compared with the control group. Conclusions: This study showed that supplementation with 0.1% MMT could enhance broiler growth, increase the small intestinal VH and the VH:CD ratio, promote the intestinal-mucosa development, affect microflora population and improve immune function in the intestinal tract of broilers. Implications: Supplementation with MMT could alter morphological changes in the intestinal villi, regulate microbial population and improve immune function in the intestinal tract, thus contributing to broiler growth. Our results indicated that MMT may serve as a natural beneficial feed additive for poultry gut health. Montmorillonite (MMT) is likely to be a potential substitute antibiotic; however, it has been less reported in broiler chickens. In this paper, we studied the effects of MMT on the growth performance, immunity, intestinal morphology and caecal microflora of broilers. We found that supplementation with MMT could enhance broiler growth, modulate microbial population and improve immune function in the intestinal tract, which may serve as a new beneficial feed additive in poultry diets. [ABSTRACT FROM AUTHOR]