Growth performance, nutrient utilization, gut integrity, short-chain fatty acids, and gene expression in...

Stimbiotic (STB) supplementation and precise inclusion of dietary fiber (DF) can increase the number of fiber-fermenting microorganisms, enhance growth performance, and increase the cecal concentration of short-chain fatty acids (SCFA), potentially improving overall gut health. 1200 male byproduct-breeder day-old chicks were allocated to six treatments in a randomized complete block design. The treatments were: 1) 0 g/kg wheat bran (WB), no STB, no challenge (NCH); 2) 0 g/kg WB, 0.1 g/kg STB, no challenge (NCH- STB); 3) 0 g/kg WB, no STB, with challenge (CH); 4) 50 g/kg WB, no STB, with challenge (CH-WB) 5) 0 g/kg WB, 0.1 g/kg STB and with challenge (CH-STB); 6) 50 g/kg WB, 0.1 g/kg STB plus the challenge (CH-WB-STB). On d13, birds were inoculated with a solution containing E. tenella, E. maxima, and E. acervulina. Data were analyzed by one-way ANOVA, and Tukey HSD was used to separate the means. During the starter phase, weight gain (WG) was greater (P < 0.05), and FCR was lower (P < 0.05) in the WB compared with the control and STB groups. Birds in NCH and NCH-STB treatments had higher (P < 0.05) WG during the acute, whole challenge, grower, and overall phases. Dry matter digestibility (DMD) was higher (P < 0.05) for NCH-STB and CH-STB, and nitrogen (N) digestibility was higher in the CH-WB and CH-WB-STB than in the NCH-STB group. GLUT-1 and CAT-1 were increased (P < 0.05) in the CH-WB than in NCH-STB group. 4EBP1 was increased (P < 0.05) in CH, CH-WB-STB than NCH and NCH-STB groups, and FBXO9 was higher in CH, CH-WB, CH-WB-STB than NCH group. On d42, CH-WB and CH-WB-STB had lower levels (P < 0.05) of isobutyrate and isovalerate than NCH-STB group. In conclusion, neither STB nor WB inclusion influenced growth performance and SCFA profile in Eimeria-challenged birds. Wheat-bran inclusion decreased ceca branched-chain fatty acids (BCFA), which suggests a lower protein fermentation in the ceca, likely as a result of modification of the ceca microbiota.