The effect of the non-starch polysaccharides levels on intestinal enzyme activity and performance of laying hens

In this investigation، the effects of inclusion of a Pishtaz wheat cultivar with high in non-starch polysaccharide and xylanase supplementation in the diet on productive performance، nutrient digestibility، and intestinal enzymes activity of laying hens was studied from 21 to 47 wk of age. Complete random design in factorial arrangement were modulated in 8 treatments with 4 levels of wheat (0، 23، 46، and 69%) corresponding to a dietary xylose content of 1. 8، 2. 0، 2. 2، and 2. 4% with or without XS. Each treatment was replicated 5 times (6 hens per each replicates). For the entire experimental period، egg weight (P<0. 05) and egg mass (P<0. 01) were reduced and feed conversion ratio (FCR) was impaired (P<0. 05) with increased levels of xylose but ADFI and egg production were not affected. Xylanase supplementation improved egg production (P<0. 05)، egg weight and egg mass (P<0. 01)، and FCR (P<0. 01). Fat digestibility (P<0. 001) and AMEn content of the diets (P<0. 05) decreased with increased levels of xylose but nitrogen retention was not affected. Xylose inclusion increased (P<0. 001) amylase in the duodenum، and aminopeptidase and lipase activity in the duodenum and jejunum. Ileal viscosity increased (P<0. 001) with level of xylose but decreased (P<0. 001) with XS. The results of the current experiment show that increasing level of xylose decreased productive performance، fat digestibility and AMEn of the diet and increased endogenous enzyme activity.