Response of Broiler Chickens to Triticale-Based Diets Supplemented with Microbial Enzymes (1. Growth and Intestinal Function)

Abstract

A total of 384 day-old male Ross 308 broiler chicks were allocated to 8 dietary treatments to examine the influence of supplementation with xylanase and phytase, individually or in combination, in diets based on two new cultivars of triticale (Bogong and Canobolas). The inclusion of phytase alone in either Bogong or Canobolas diets increased (P < 0.01) feed intake and body weight; however, the effect of grain was not significant. The ileal digestibility of crude protein, gross energy, starch, calcium, and phosphorus was increased by inclusion of phytase and xylanase (P < 0.05). The interaction between xylanase and phytase positively influenced (P < 0.01) the digestibility of crude protein, gross energy, calcium, and phosphorus. Ileal viscosity was decreased ( P < 0.05) by the inclusion of xylanase and phytase individually o r in combination. The inclusion of phytase and xylanase increased (P < 0.001) the phytate-P degradation. Birds on Bogong-based diet ha d a higher (P < 0.05) degradation of phytate than those on the Canobolas- based diet. The weight of various visceral organs on day 7 was not affected by the inclusion of enzymes, nevertheless the weight of proventriculus plus gizzard was higher (P < 0.01) for chickens offered Canobolas-based than chicks on the Bogong-based diets. On day 21, the liver weight was reduced (P < 0.001) by the inclusion of phytase. An interaction (P < 0.01) between grain and phytase inclusion led to an increased weight of proventriculus plus gizzard on t h e Bogong diets with phytase. The inclusion of xylanase increased (P < 0.01) maltase activity a t the jejunum on day 7, while it decreased the pancreatic protein content on day 21. The activity of chymotrypsin amidase was reduced (P < 0.01) by the inclusion of phytase. These results show that supplementation of phytase and xylanase to triticale-based diets can improve broiler performance by increasing the activities of some digestive enzymes and nutrient utilization.