The study was conducted to evaluate the effects of using pomegranate (Punica granatum L.) by-product powder (PBP) as a natural growth promoter in rabbit diets on growth performance. A total of 36 male New Zeeland White (NZW) rabbits was randomly assigned to four groups containing 9 rabbits each in 3 replicates and raised from 5 to 13 weeks of age and nearly equal average initial live body weight (561.67 ± 6.68 g). The experimental groups, the first group was fed basal diet control without PBP as control, while the second, third and fourth groups were supplemented with 1.0, 1.5 and 2.0% of PBP, respectively.
The obtained results demonstrated that rabbits fed diet supplemented with1.5% of PBP had the heaviest (P<0.05) final body weight and average daily weight gain followed by those received 2.0, 1.0% and control groups. Rabbit groups fed diets supplemented with 1.0, 1.5 or 2.0% PBP recorded significantly (P<0.05) higher digestibility of DM, OM, CP, and CF compared to the control group. Besides, the digestibility of DM, OM, CP, CF and NFE were higher (P<0.05) with rabbits group fed diet supplemented with 2.0% PBP than the other tested groups. Moreover, data of nutritive values illustrated that rabbit group fed 1.5% or 2.00%PBP recorded the highest (P<0.05) values of DCP, TDN and DE compared to the other tested groups. Supplementation of PBP had no effect on meat CP content. While, there were significantly (P<0.05) decrease in EE meat content of rabbits group fed diet supplemented with 1.0 and 2.0% of PBP than the control group. The supplementation of PBP increased (P<0.05) plasma total protein, albumin and globulin levels compared to those of rabbits fed the control diet. The blood plasma content of glucose, total lipids, total cholesterol and LDL was observed to move down constant with increasing dietary levels of PBP (1.0, 1.5 and 2.0 %), respectively. Also, the values of T-AOC, SOD, CAT and GSH-Px were significantly (p < 0.05) increased with increasing PBP levels in rabbit diets. Additionally, rabbits fed 1.5% PBP diet recorded the best net revenue.
Conclusively, the results suggest that the pomegranate (PBP) by-product powder could be supplied in rabbit diets at 1.5% to achieve best performance and economical efficiency without any adverse effect on rabbit's heath.