In vitro bile acid-binding capacity of dietary fibre sources and their effects with bile acid on broiler chicken performance and lipid digestibility.

A 4 × 2 factorial experiment was conducted to study the effect of feeding diets-containing dietary fibre (DF) sources and a source of bile acid (BA) on growth performance and lipid metabolism. In addition, in vitro BA-binding capacity of fibre sources was investigated. A total of 256 one-d-old male broiler chickens (Ross 308) were assigned to DF sources [maize-soybean meal (control, C), or 30 g/kg of wheat bran (WB), barley bran (BB) or soybean hulls (SH)] and BA (with or without 1.5 g Na-deoxycholate/kg). Each treatment was replicated 4 times with 8 broiler chickens per cage. The highest in vitro BA-binding capacity was observed with BB (8.76 mg/g BB). From 0 to 21 d, with the addition of BA, the average daily feed intake (ADFI) decreased in broiler chickens fed on the C, WB or BB diets, while there was no difference with the SH diet. With added BA, the average daily gain decreased in broiler chickens fed on the C or SH diets, but it did not change in those fed on the other diets. The addition of BA decreased feed conversion ratio (FCR) in broiler chickens fed on the BB or WB diets, but it increased in those fed on the C or SH diets. Interaction results indicated that the apparent ileal digestibility of lipid increased in broiler chickens fed the C and other DF diets with BA compared to those fed the diets without BA. The addition of BA decreased the pancreas lipase activity (PLA) in broiler chickens fed on the C diet compared to those fed the C diet without BA, while no changes observed in those fed the DF diets with or without BA. No interaction was observed in total liver bile acid (TLBA). The WB, BB and SH with little Na-deoxycholate-binding capacity (<10 mg/g of DF) under in vitro conditions had particular effects with BA on the measured criteria in broiler chickens. The magnitude of improvement in digestibility of lipid with the addition of BA depends on the source of fibre used and the addition of BA in DF diets had little effect on growth performance in young broiler chicken diets.