Response of Growing Rabbits to Diets Containing Different Levels of Wheat Screening by-Product With or Without Enzyme Supplementation

Abstract

A total number of one hundred weanling New Zealand White rabbits aged five weeks were used in this study. Rabbits were randomly distributed into ten experimental treatments; each one contains 5 males and 5 females in individual cages. Five levels (0, 5, 10, 15 and 20 %) of wheat screening by-product (WSP) and each level was fed without or with addition of enzyme preparation in 5×2 factorial design arrangement. Enzyme preparation ( containing β-Xylanase and α-Amylase) was added at 0 and 500 g/ ton of diets, during the experimental period from 5 to 12 weeks of age.The obtained results could be summarized as follows: The rabbits fed diet containing 5% WSP with enzymes significantly recorded the highest values of body weight, body weight gain and relative growth rate followed by those fed diet containing 10% WSP with enzyme addition. The rabbits fed diet containing 20% WSP without enzymes recorded the lowest significant values in these respects. The rabbits fed diet containing 20% WSP with enzymes consumed the highest amount of feed compared with those for other groups. The best feed conversion ratio was recorded for rabbits fed diet containing 5% WSP with enzymes additions followed by those for control, 10 and 15% WSP with enzymes addition compared with all other dietary treatments. Enzymes supplementation in diets containing WSP significantly improved the digestibility coefficients of nutrients and carcass traits of rabbits compared with other groups. Total protein, cholesterol and urea were significantly decreased by increasing the level of WSP in the experimental diets. However, the differences between rabbits fed diets containing different levels of WSP with or without enzymes addition and the control diet in albumin and globulin was not significant. Rabbits fed diets containing different levels of WSP and provided with enzymes recorded significantly the lowest values of cholesterol compared with those fed the diets containing WSP without enzymes and control diet. 106 ABAZA AND OMARAThe addition of enzymes in diets containing WSP significantly improved the liver functions. Chemical composition of meat did not significantly differ with the WSP and enzymes addition. Results showed an improvement in average values of net revenue, economical efficiency and relative economical efficiency due to feeding growing rabbits on diet containing 5% WSP with enzyme preparation.In conclusion, use of the WSP can be successfully fed at level 5 % of growing rabbit diets with enzymes supplementation (β-xylanase; αamylase) without any adverse effect on growth performance and economical efficiency, under Egyptian conditions.