Effects of lysolecithin and xylanase supplementation on the growth performance, nutrient digestibility and lipogenic gene expression in broilers fed low-energy wheat-based diets.

This experiment was conducted to evaluate the effects of emulsifier (Lipidol, active ingredient: lysophospholipids; LPL) and xylanase (200 mg/kg of feed) supplementation in a lower energy diet on performance, nutrient retention, intestinal morphology, blood metabolites and meat quality in broilers. A total of 360 1-day-old male chicks (Ross 308) were assigned to five treatments, with six replications of 12 birds each per treatment in a completely randomized design. The five treatments were as follows: (a) higher energy diet (HE); (b) lower energy diet (LE; energy content reduced by 100 kcal/kg compared with the HE); (c) LE + 0.10% LPL (EM); (d) LE + 200 mg xylanase/kg (ENZ); and (e) LE + 0.10% LPL + 200 mg xylanase/kg (EM + ENZ). Broilers fed HE had a higher average daily gain (ADG, day 0-24) and lower average daily feed intake (ADFI) and feed conversion ratio (FCR) from day 11 to 24 and day 0 to 24 than those fed the LE diet. Broilers fed EM or ENZ diets also had lower FCR and ADFI (day 11-24 and day 0-24) than those fed reduced-energy diets. The inclusion of 0.10% LPL and/or xylanase to the LE diet increased the apparent digestibility of dry matter (DM), nitrogen (N), ether extract (EE) and gross energy (GE), as well as villous height and ratio of villous height to crypt depth in the duodenum and jejunum. Serum free fatty acid (FFA) concentration was lower in birds fed the HE diet, compared with those fed the LE diet. The low-density lipoprotein cholesterol, total cholesterol and triglyceride concentrations were decreased by LPL supplementation. The relative weight of abdominal fat was higher in birds fed the HE diet, but lower from LPL supplementation. It was concluded that a reduced-energy diet impaired bird performance, while dietary supplementation of LPL and xylanase to reduced-energy diets positively affected productive performance, nutrient utilization, intestinal morphology and abdominal fat percentage.