Dietary resistant starch modifies the composition and function of caecal microbiota of broilers.

Background: Diet plays an important role in shaping the composition of gut microbiota. Starch is the main source of carbohydrates in diets of broilers. This study investigated the effects of dietary corn starch and resistant starch on composition and function of caecal microbiota of broilers. A total of 320, 1-day-old male Arbor Acres broiler chicks were randomly assigned into five groups including normal corn-soybean (NC) diet, corn starch (CS) diet group, 4%, 8% and 12% resistant starch (RS) diet groups. The caecal contents of 42-day old broilers were sampled and microbiota community was analysed with 16S rRNA gene sequences.
Results: The CS group increased the abundances of Bilophila, Eggerthella, Olsenella and Sellimonas and decreased proportion of Akkermansia, Eisenbergiella, Oscillospira, Ruminococcaceae NK4A214 group and Synergistes in the caecum of birds compared to the NC group. However, the birds from RS groups had higher abundances of Anaerofilum, Bacteroides, Desulfovibrio and Parasutterella and lower abundances of Alistipes, Bilophila, Christensenellaceae R-7 group, Eggerthella and Ruminiclostridium 1 than the CS group. Functional prediction of these changes in microbiota revealed that the CS diet drove caecal microbiota that were more inclined to utilize carbohydrates through glycolysis/gluconeogenesis metabolism, while the 8%RS and 12%RS diets depleted microbial glycolysis/gluconeogenesis and amino acids metabolism.
Conclusion: Dietary CS and RS alter the microbial composition and diversity, and modulate the metabolic pathways of microbial metabolism in caecum of broilers, which may further affect nutrient utilization and hindgut health of the host. © 2019 Society of Chemical Industry.
(© 2019 Society of Chemical Industry.)