Effects of bile acid and cholesterol in diets contained fiber on intestinal morphology and broiler chicken performance

Two experiments were conducted to investigate interactions of wheat bran, barley bran, or soybean hulls with sodium deoxycholate and cholesterol in broiler chickens. A completely randomize design was used with a 4×2 factorial arrangement and 256 one-day old broiler chickens (Ross 308) with 8 experimental diets in 4 replicates of 8 birds per replicate for each experiment. Factors for first experiment were included dietary fibers (wheat bran, barley bran, or soybean hulls (3% for each fiber) and control), and bile acid (0.0 and 0.15%). Factors for second experiment were included dietary fibers (similar to first experiment) and cholesterol (0.0 and 0.15%). The results of the first experiment showed that the inclusion of bile acid in diet was significantly decrease feed intake and body weight gain (P<0.05). Treatments contained wheat bran and barley bran led to increases in feed conversion ratio (P<0.05). On the other hand, feed conversion ratio was improved by inclusion of bile acid in diets contained wheat bran and barley bran rather corresponded diets (P<0.05). The inclusion of bile acid led to decreases in villi index (P<0.05). On the other hand, the inclusion of barley bran in diet resulted in increases in villous surface area and villi index (P<0.05). Only the addition of bile acid in diet contained soybean hulls led to decreases in villous surface area rather corresponded diets (P<0.05). The results of the second experiment showed that the inclusion of cholesterol in diets led to decreases in body weight gain (P<0.05). The effect of fiber and interaction showed that all experimental diets rather control caused a decreases in body weight gain (P<0.05). Meanwhile interaction showed that all experimental diets was increased feed conversion ratio rather control (P<0.05). The diet contained soybean hulls led to the highest crypt depth and the lowest vilii index (P<0.05). The lowest villous height was related to diets contained soybean hulls + cholesterol (P<0.05). The results of current study have shown that fiber type had different effects on intestinal morphology. The inclusion of soybean hulls in diet had more antinutritional effects rather other tested fibers. The inclusion of bile acid and cholesterol in diets could not decrease antinutritional effects of soybean hulls on intestinal morphology. Although the inclusion of bile acid in diets cased some modulation in performance but the inclusion of cholesterol in diets did not show such ability.