EFFECT OF SUPPLEMENTAL ZINC AND COPPER ON PERFORMANCE OF GROWING RABBITS

Document Type : Original Article

Authors

Anim. Prod. Dept., Fac. Agric., Zagazig Univ., Egypt

Abstract

Forty-two New Zealand White male rabbits with average body weight 546.74g were randomly assigned to 7 groups (6 animals in each) in a completely randomized design to study the effect of dietary zinc supplementation through inorganic (ZnO) or organic (Zinc EDTA) sources in combinations with copper (CuSo4) on growth performance. Rabbits of the first group (T1) were given basal diet without any supplementations (control group), while the other 6 groups were given basal diet containing zinc and copper as follows:  group 2 (T2) received basal diet + 250 mg Cu/kg diet from CuSo4, group 3 (T3) received basal diet + 500  mg Cu/kg diet, group 4 (T4) received basal diet +20 mg Zn from Zinc EDTA + 250 mg Cu/kg diet, group 5 (T5) received basal diet + 20 mg Zn from Zinc EDTA + 500 mg Cu/kg diet, group 6 (T6) received basal diet +20 mg Zn from ZnO + 250 mg Cu/kg diet and group 7 (T7) received basal diet + 20 mg Zn from ZnO + 500 mg Cu/kg diet, respectively. Live body weight, daily body gain, daily feed intake andfeed conversion ratio were significantly increased by feeding rabbits on diets supplemented with 250 or 500 mg Cu/ kg diet. More enhancements were recorded in rabbits fed with 20 mg zinc as ZnO and 250 mg copper (T6). Total protein concentration in blood serum was significantly increased in rabbits fed 20 mg Zn from Zn EDTA + 500 mg Cu/kg diet (T5). Also the same treatment increased ceriatenine (CREAT) concentration in blood serum. While, Cu supplementations at 250 (T2) or 500 (T3) mg/kg feed increased urea concentration. All supplementation treatments significantly increased pre-slaughter weight comparing to un-supplemented control rabbits. The highest pre-slaughter weight was found in rabbits fed with diet containing 250 mg Cu/kg diet (T2) or with 20 mg Zn from ZnO + 250 mg Cu/kg diet (T6). Weights of carcass, liver and kidney and dressing (%) as well as weights of head and hind part did not significantly affected with the tested supplementations.Economically final margin was increased in all rabbits fed supplemented feed. The highest income from gain and the highest final margin were recorded in rabbit groups fed diet supplemented with 250 mg Cu/kg diet (T2) or 20 mg Zn from ZnO + 250 mg Cu/kg diet (T6).

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