Effect of xylanase and (beta)-glucanase supplementation of wheat- or wheat- and barley-based diets on the performance of male turkeys

The efficiency of a mixture of xylanase and ?-glucanase enzymes was evaluated in two separate experiments on growing turkeys offered diets based on wheat or wheat and barley. 2. In the first experiment, the addition of 560 and 2800 IU of xylanase and ?-glucanase, respectively, per kg of diet significantly improved feed efficiency in turkeys fed on wheat- and barley-based diet throughout the entire experiment (42 d). 3. In the second experiment, the enzyme mixture significantly increased N-corrected apparent metabolisable energy (AMEN) by approximately 5%. 4. Furthermore, the combination of xylanase and ?-glucanase significantly improved body weight gain and feed efficiency. Feed efficiency was increased by 2·94, 2·47 and 5·91% in diets based on 500 then 540 g of wheat/kg of diet, 394 then 384 g of wheat and 100 then 150 g of barley/kg of diet and 180 g of wheat and 300 then 350 g of barley/kg of diet, respectively. 5. This enzyme mixture decreased in vitro viscosity of wheat, barley and soybean meal, the effect being larger for wheat and barley than for soybean meal. 6. In conclusion, the supplementation of diets based on wheat and barley with xylanase and ?-glucanase significantly improved body weight gain and feed efficiency. Therefore, wheat and barley could be used more efficiently by turkeys in the presence of an appropriate enzyme preparation.