EFFECT OF A CARBOHYDRASE IN AN ENERGY-RED UCED AND WHEAT-BASED DIET FOR LAYING HENS

In a trial with 8 x 180 laying hens (LSL white), the effect of 450 ppm Biofeed Plus CT (diet B) was tested in a wheat-based and energy-reduc ed diet (diet C) and compared with a standard diet (diet A). Diet A wa s given to two units and diets B and C to three units each. The diets were fed ad libitum as crumbs and tested in three phases (21.-48., 49. -64., 65.-80. week). Nutrient contents of phase-1 diets were increased , whereas diets of phase 2 and 3 should only differing in components, but not in nutrient content. No differences could be seen in egg produ ction (83,5%) and egg weight (64,7 g). Effects in food consumption (11 8,0-121,4g/Tag) were not significant. Reduction of dietary ME content by 0,4-0,5 MJ per kg feed was followed by a negative effect in feed ef ficiency (3,5%), which could be partly compensated by the enzyme (abou t 50%). Due to the enzyme supplementation, ME consumption per kg egg m ass was significantly improved from week 21 to 48 (0,55 MJ). No more e nzyme effect could be seen for phase 2, whereas a higher dietary ME co ntent seemed to increase ME consumption per kg egg mass. In phase 3, n either an enzyme nor a ME-effect could be seen on ME utilization. Anim al weights of the enzyme diet were significantly higher at the end of the trial (+ 54 g). Increasing dietary ME content led to more normal e ggs (53-65 g) instead of large ones (> 65 g). Only a small reduction i n the sum of dirty, broken and small eggs could be observed due to the enzyme supplementation.