This study was conducted to investigate the effect of incorporating processing waste of dried green bean (Phaseolus vulgaris) (GBPW) in diets of growing NZW rabbits on nutrients digestibility, live body weight, body weight gain, carcass traits and some blood parameters. Fifty –six New Zealand White (NZW) rabbits were chosen after weaned at 6 weeks of age and randomly divided into four groups (14 rabbits/group) according the their initial live body weight (740±20 g). The experimental period extended from 6 to 14 weeks of age. Four pelleted experimental diets were formulated to be approximately isocaloric, isonitrogenous and isofibrous. Dried green bean processing waste (GBPW) was incorporated at levels of 0, 10, 20 and 30% for rabbit groups, G0 (as control), G1, G2 and G3, respectively. At the end of the feeding experimental (14 weeks of age), digestibility trials were conducted to determined the nutrients digestibility and feeding values of the experimental diets. Three rabbits were slaughtered from each group to test the carcass traits and some blood plasma parameters. Results revealed that the chemical composition of GBPW recorded 87.78, 80.43, 22.37, 29.00, 4.37, 19.57 and 24.69%, respectively for DM, OM, CP, CF, EE, Ash and NFE. Significant differences (P<0.05) between control diet (G0) and tested diet (G3) in digestion coefficients of OM, CP and CF as well as the feeding values (DCP and DE) which had highest values. Inversely the tested diets did not differ significantly with control one in digestion coefficients of DM, EE and NFE, as well as TDN value. No significant differences among dietary groups in live body weight at 6 and 10 weeks with the highest values 779.29 and 1477.5g, respectively in G3. On the other hand, the live body weight at 14 weeks was significantly affected (P<0.05) by the level of incorporating GBPW in diets with the highest value (2100g) in G3 compared with control group G0 and G1. The same trend was found for total body gain (6-14 weeks) and daily gain, where G3 recorded the highest values. Insignificant differences among the experimental diets respecting feed conversion, however, G1 had the better one in the period 6-14 weeks of age. The green bean processing wastes (GBPW) levels had no significant effect on most carcass traits, G1 had the higher of liver weight and edible giblet percentage. In respect to chemical composition of rabbit's meat on DM basis, the experimental diets did not significantly effect on DM, CP and ash, while, EE percentage was affected especially for G3 as it had the highest value. On the other hand, chemical composition of fresh meat showed that higher CP% was found for G0, the lower was for G3, while, the later had the higher EE content and G1 was lower one. No significant differences for DM and ash contents were found among the groups. No significant differences in blood plasma total protein and globulin were showed among the experimental diets. Plasma albumin, ALT, AST, urea and total cholesterol were significantly affected (P<0.05) by experimental diets. Less albumin, ALT and AST were shown by G0, while less urea and cholesterol was recorded for G3. On the other hand, higher urea and cholesterol was shown by G0. Increase the rate of incorporating the GBPW from 0 to 30% in experimental diets lead to improvement in economic efficiency and relative economic efficiency. In conclusion dried green bean processing wastes could be used in feeding of growing rabbits up to 30% with no adverse effect on productive performance, carcass traits, physiological function and economical efficiency.
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