PSXI-36 Evaluation of fecal microbiota of dogs fed extruded diets containing white and red sorghum as primary carbohydrate source

Abstract

Abstract Sorghum (Sorghum bicolor) is a cereal grain consisting of either white, yellow, red, brown or black endosperms. In human and pet nutrition, sorghum has gained increased attention as a gluten-free and non-GMO whole-grain option. However, a paucity of information exists about the effect of this cereal grain on the GI microbiome and host health. Therefore, the aim of this study was to evaluate the effects of extruded diets containing corn (CON), white sorghum (WHS) or red sorghum (RES) as the main carbohydrate source on fecal microbiota and metabolites in dogs. Animal care protocol used in this study was approved by the Institutional Care and Use Committee at the University of Illinois. Three diets containing either 30% of CON, WHS, or RES were formulated to meet or exceed the AAFCO (2018) nutrient profile for adult dogs. Nine adult female beagles were randomly assigned to one of the 3 dietary treatments using a replicated 3x3 Latin square design. Each experiment period consisted of 14d (10d of diet adaption and 4d of fecal collection). Fresh fecal samples were collected and allocated for microbial analysis. Illumina 16S rRNA sequencing from V4 region was completed using MiSeq and analyzed using QIIME 2. Linear models were used to evaluate the main effect of treatment. Over 1.8 million sequences were generated. Samples were rarified to 42,160 reads for analysis of diversity and species richness. Beta-diversity did not differ among dogs fed CON, WHS, or RES diets (q- and p-values > 0.05). Similarly, microbial richness was also not affected by treatment. Overall, fecal metabolite concentrations were similar among treatments and did not have a strong correlated with microbial taxa. Our findings indicate that extruded diets using sorghum as a substitute for corn as the main dietary carbohydrate result in similar fecal metabolite profile and microbiota in adult dogs.