INFLUENCE OF USING ROCKET SEED (Eruca sative) OIL AND ONION SEED (Allium cepa) OIL ON PRODUCTIVE AND PHYSIOLOGICAL PERFORMANCE OF GROWING RABBITS UNDER HOT CLIMATE CONDITION

A completely random experiment was conducted to evaluate rocket and onion seed oils or their mixture under climate summer conditions on growth performance, carcass traits, rectal temperature, respiration rate, immunity (antibody titer against SRBC’S), blood biochemistry, digestibility coefficients, and economical efficiency of growing rabbits, from July to September, 2009 .The averages of daily ambient temperature, relative humidity and temperature humidity index (THl) inside the building were 30.27 ±0.68°C, 75.95±2.88% and 29.36, respectively.             A total of 96 NZW rabbits, weaned at 6 weeks of age with an average initial body weight, 623.00 ± 3.09,g were randomly distributed to four experimental treatments (24 rabbits/ each) then divided into 3 replicates of eight rabbits each. Rabbits were fed the basal diet either unsupplemented (control) or supplemented with 1g rocket seed oil/Kg diet, or 1g onion seed oil/ Kg diet and their combination throughout the whole experimental period which lasted for 12 weeks. The experimental basal diet was isonitrogenous (CP=17 %) and isocaloric (2500 Kcal/Kg DE). Results obtained showed that percentages of total unsaturated fatty acids, especially polyunsaturated fatty acid (linoleic) in onion oil were higher than in rocket oil. The percentage of fatty acid Erucic was higher in rocket oil than those in onion oil. Under the high ambient temperatures final body weight and carcass traits of growing rabbits were significantly (P<0.05) increased and feed conversion values were improved with dietary supplementation with either rocket oil or onion oils or their mixtures compared with the control group.Dietary either rocket or onion oil and their mixture of growing rabbits ameliorated some of the adverse effects of heat stress on immune response, rectal temperature and respiration rate. Dietary supplementation, also improved (P≤0.05) antibody titer against SRBC’S as compared with the control. Serum total protein and albumin were significantly increased (P ≤ 0.05) while, serum total lipids, glucose, AST and ALT concentrations were significantly decreased (P ≤ 0.05) due to dietary rocket oil only or with onion oil as compared with the control group. Digestibility coefficients of CP and EE were significantly (P<0.05) affected by dietary addition, being the highest for rocket oil diet, followed by rocket +onion oils diet as compared with the control group. Rocket oil fed group recorded the highest (P<0.05) net return, best economical efficiency and performance index followed by those fed rocket oil plus onion oil and onion oil treatments as compared with the control group. In conclusion, supplementation of rocket and onion seed oils in growing rabbit diets enhanced growth performance carcass weight and digestibility coefficient of CP, EE and elevated the immunity as well as reduced rectal temperature and respiration rate when growing rabbits were subjected to heat stress.