A completely random experiment was conducted to evaluate onion and moringa seed oils or their mixture under climate summer conditions on growth performance, carcass traits, rectal temperature, respiration rate, blood biochemistry, digestibility coefficients, and economic efficiency of growing rabbits, from June, to August, 2015.A total of 108 Bauscat rabbits, weaned at 5 weeks of age with an average initial body weight of 528.80 ± 1.49,g were randomly distributed into four experimental treatments (27 rabbits/ each) and each treatment was sub-divided four 3 replicates of nine rabbits each. Rabbits were fed the basal diet either un supplemented or supplemented with 1g onion seed oil/Kg diet, or 1gmoringaseed oil/Kg diet and their combination 0.5 g onion seed oil + 0.5 g moringa oil/Kg diet throughout the whole experimental period which lasted for 3 months. The experimental basal diet was isonitrogenous (CP=17.0 %) and isocaloric (2536 Kcal/Kg DE).
Results obtained showed thatthe percentages of total saturated fatty acids (TSFA) in moringa oil (23.88%) were higher than in onion oil (8.71%). Moringa oil contains a high level of monounsaturated fatty acids (MUSFAs) especially oleic acid (71.43%) than onion oil (8.71%). Total unsaturated fatty acids (TUSFAs), especially PUSFAs (linoleic) in onion oil were higher than that in moringa oil .Under the high ambient temperatures final body weight, daily gain and total gain of growing rabbits were significantly (P ≤ 0.05) increased and feed conversion values were improved with dietary supplementation with either moringa oil or onion oil and their mixture compared with those of the control group from 5-17 weeks of age. However, feed intake and viability rate were not significantly influenced by experimental dietary supplementations during the experimental periods. Hot carcass weight and dressing % were significantly (P≤0.05) higher for growing rabbits fed diets supplemented with onion oil as compared with those fed the control diet. Dietary either onion or moringa oil and their mixture ameliorated some of the adverse effects of heat stress on rectal temperature and respiration rate. Serum total protein (TP) and globulin (Glb), digestibility coefficients of CP and EE were significantly increased (P ≤ 0.05) while, serum total lipids, cholesterol and glucose concentrations were significantly decreased (P ≤ 0.05) due to dietary onion oil only or with moringa oil as compared with the control group. Onion oil plus moringa oil fed group recorded the highest (P ≤ 0.05) net return and best economical efficiency followed by those fed onion oil treatments as compared with the control group.
In conclusion, results of the experiment concluded that addition of 1g/Kg diet mixture of onion and moringa seed enhanced growth performance carcass weight and digestibility coefficient of CP, EE and reduced rectal temperature and respiration rate when growing rabbits were subjected to heat stress.