INFLUENCE OF USING DIETARY ANTIOXIDANT ON PRODUCTIVE AND REPRODUCTIVE PERFORMANCE OF MANDARA STRAINS UNDER SUMMER CONDITIONS

The present study aimed to investigate the influence of the dietary antioxidant addition to the basal diet on productive and reproductive performance of Mandara strains under summer conditions. A total number of 147 laying hens and 21 cocks at 24 weeks of age was allocated to 7 treatment groups (21 hens + 3 cocks / each treatment) until 36 weeks of age. The birds within each treatment were fed as follows:T1: Basal diet only without supplementation (served as a control), T2: Basal diet and 100 mg Vitamin C /kg feed, T3: Basal diet + 100 mg Vitamin E /kg feed, T4: Basal diet + 100 mg Vitamin C + E /kg feed, T5: Basal diet + 200 ml rosemary oil /kg feed, T6: Basal diet + 200 ml oregano oil /kg feed and T7: Basal diet + 100 ml rosemary and oregano oils as medicinal plants /kg feed, respectively. The obtained results showed that, the major percentage components of rosemary and oregano oils by Gas chromatographymass spectrometry (GC—MS) analysis were 1.8-cineole (44.33), αPinene (16.38) and Carvacrol (65.41) and p-cymene (14.58), respectively. Under the high ambient temperatures dietary oregano oil, Vitamin C, rosemary oil and an equal mixture of Vitamin C + E added to the basal basal diet were significantly (P≤0.05) increased the percentage of egg production and egg mass of Mandara layers. However, rosemary oil and an equal mixture of Vitamin C + E added to the diet were significantly (P≤0.05) heavier of egg weight than nonsupplemented groups during the whole experimental period. Combinations of rosemary and oregano oils, combination of Vitamin C and E, rosemary oil, oregano oil, Vitamin C, Vitamin E alone in the diet treated groups were significantly (P≤0.05) enhancement of fertile eggs (%), hatchability/total eggs (%), sperm motility and sperm-cell concentration (X 10 9 /ml) and decreased yolk cholesterol, serum