Combination of emulsifier and xylanase in wheat diets of broiler chickens

The present study was conducted to investigate the effect of emulsifier, xylanase, and a combination of both on the digestibility of nutrients and growth performance of broiler chickens. A total of 480 1-day-old male broiler chickens (Ross 308) were randomly assigned to four dietary treatment groups (15 replicate pens with 8 birds each): control (CON), control plus xylanase (XYL), control plus emulsifier (EMU), and control plus xylanase and emulsifier (XYL+EMU). The experiment was conducted for a period of 42 days, and the diets were based mainly on wheat, soybean meal, tallow, and rapeseed oil. The addition of emulsifiers to the diet showed a significant effect on body weight gain (BWG) (P < 0.001) and feed conversion ratio (FCR) of the chickens during the grower period (P < 0.001) and on the overall FCR (P < 0.001). The analysis of the digestibility of fatty acids on day 35 of the study indicated a positive influence of emulsifier addition, with the highest increase recorded for polyunsaturated fatty acids (P < 0.001). No significant differences in gene expression were noted on the 35th day of birds’ life, but an increase in the expression of some proteins encoding membrane transporters was observed (P < 0.05). The combined use of xylanase and emulsifier resulted in more than a threefold increase in the degradation of neutral detergent fiber (P < 0.05). In conclusion, the combined use of emulsifier and xylanase in wheat–soy-based diets for poultry improves apparent prececal digestibility of fatty acids, and crude protein, apparent metabolizable energy corrected to N equilibrium, and total tract neutral detergent fiber degradation, resulting in better BWG and FCR values. However, the use of emulsifier and xylanase combination showed no additive effect on the investigated variables. The results obtained in the current study indicate that supplementation with a combination of emulsifier and xylanase can be an effective feeding strategy to improve poultry production and nutrient utilization. Future studies are warranted to investigate the effect of emulsifier and xylanase combination on amylase secretion, as well as on the digestibility of other nutrients (crude protein).