Effects of the Dietary Inclusion of Xylanase on the Performance and Jejunum Morphometry of Meat-Type Quails

ABSTRACT The objective of this study was to evaluate the effects of the supplementation of two xylanase products to diets with reduced metabolizable energy fed to meat-type quails during the starter phase (1-14 days). A completely randomized experimental design in a 2 x 3 + 1 factorial arrangement two reduced metabolizable energy (ME) diets, inclusion or not of xylanase, and a control diet with no enzyme addition) was applied, totaling seven treatments with five replicates of 45 quails each. At 14 days of age, jejunum segments were collected for morphometry evaluation. No interaction between the studied factors were detected for performance and jejunal morphometry parameters. Body weight, weight gain, feed intake and feed conversion were not influenced by enzyme inclusion. Reduced ME diets (-70 or -140 kcal/kg) did not affect performance, except for feed intake. Xylanase inclusion increased villus height and villus:crypt ratio. Therefore, xylanase supplementation can be effective in corn and soybean meal-based diets, without causing any impairment in the performance of 1- to 14-day-old quails. Xylanases A and B were more efficient when dietary energy level was reduced in 140 kcal ME/kg, and were also shown to effectively improve the jejunal morphometry of starter meat-type quails.