INFLUENCE OF USING PLANT FEED ADDITIVES AS GROWTH PROMOTERS ON PRODUCTIVE PERFORMANCE OF GROWING RABBITS

The present study aimed to investigate the effect of dietary supplementation with rocket (Eruca Sativa) seeds, carrot (Daucus Carota L.) seeds or bay laurel leaves (Laurus Nobilis L.) and their mixtures on productive performance of growing rabbits. Ninety six male growing New Zealand White (NZW) rabbits (five weeks old) with an average live body weight of 512 g were chosen and randomly divided into 8 equal groups. The Control group (T1) was fed free basal diet. The other experimental groups received the basal diet and over top were fed on 1.0% rocket seed (T2), 1.0% carrot seed (T3), 1.0% bay  laurel leaves (T4), 0.5% rocket seed+0.5% carrot seed (T5), 0.5% carrot seed+0.5% bay laurel leaves (T6),0.5% rocket seed+0.5% bay laurel leaves (T7) and 0.33% rocket seed+0.33% carrot seed+0.33% bay laurel leaves in diet (T8), respectively. The growth trial lasted for 8 weeks. The results showed that only at 9 week of age, rabbits of T2, T5, T6 and T7 followed by T8 tested diets gave significant (p=0.0026) higher live body weight compared with T1 which disappeared at 13 weeks of age. Total body weight gain significantly (p=0.0035) improved for tested groups at 5-9 weeks of age, however, the total growth (5-13 weeks) rabbits received 0.33% rocket seed+0.33% carrot seed+0.33% bay laurel leaves (T8) gave significantly (p=0.0395) the highest total body weight gain compared to control group. At 5-13 week, the control group had the highest feed consumption (p=0.0517) compared to all tested groups. Feed conversion ratio was significantly affected by dietary treatments during experimental intervals. The control group recorded the worst FCR during 5-13 weeks of age (p=0.0124).Digestibility coefficients of crude protein (P=0.05) and crude fiber (p=0.004) were significantly improved as a response to feeding tested materials except in case of 1% carrot seeds compared to the control. Further improvements in digestibility coefficients of EE (P=0.0001) and NFE (p=0.01) for all tested diets against the control were recorded. Nutritive values of the experimental diets in terms of TDN (p=0.04) and ME (p=0.05) were significantly influenced, while DCP was not affected. At the same time, T8 appeared to the highest TDN value (57.81%), while T7 tended to the highest ME value (2406.8cal/kg) compared to the others. N balance was significantly greater (p=0.05) in rabbits fed rocket seeds or carrot seeds or bay laurel leaves supplemental diets than those fed control. The highest value (2.30) was recorded with group feeding T8 diet. Rabbits fed diets contain feed additives as rocket seed, carrot seed or bay laurel leaves recorded significantly decreased (P=0.004) values of glucose concentration for all supplemented groups except for T8 compared with control group. Total lipids (p=0.0001), total cholesterol (p=0.001) and triglycerides (p=0.05), LDL cholesterol (p=0.05) and VLDL cholesterol (p=0.05) were significantly affected by dietary treatments. Regarding antioxidant activities, there were significant increases in TAC (p=0.05) and a decrease in lipid peroxidation upon feeding the tested groups in contrast to the control. Favorably, dressing % for group received T8 diet significantly (P=0.001) increased (69.10%) followed by the other tested diets compared to the control. On contrarily, NH3-N concentration was significantly (p=0.01) decreased while VFA’S concentrations significantly (p=0.05) increased in all groups of rocket seeds or carrot seeds or bay laurel leaves supplemental diets compared with control. The experimental groups recorded lower feed cost/rabbit values than control group. So, the experimental groups had higher values of economic efficiency and relative economic efficiency compared control. T8 diet achieved the highest values of economic efficiency and relative economic efficiency being 1.129 and 138%, respectively.