PHYSICAL SEMEN CHARACTERISTICS, REACTION TIME AND BLOOD METABOLITES OF HI-PLUS BUCK RABBITS INFLUENCED BY MICROALGAE AND PROBIOTICS AS FEED ADDITIVES UNDER HOT CONDITIONS IN EGYPT

A total number of 40 Hi-Plus buck rabbits were divided into four equals groups: the 1^st group (C, n = 10), bucks served as control without supplementation. The 2^nd, 3^rd and 4^th groups, bucks received 10 g of miceoalgae Spirulina platensis (SP) / kg basal diet, 10 g of ZADO^® / kg basal diet and 10 g of YEAST^®/ kg basal diet, respectively. Plasma total protein, globulin, glucose, total antioxidant capacity and triiodothyronine hormone concentrations were increased (P<0.05) in the buck rabbits groups fed on SP, ZADO and YEAST compared to the bucks of the control group. However, total cholesterol and triglycerides were decreased (P<0.05) in the buck rabbits fed ZADO and YEAST compared with the control group. Alanine aminotransferase concentration decreased (P<0.05) in the buck rabbits of SP and YEAST compared to the control group. No significant differences were found in plasma aspartate aminotransferase, creatinine and urea concentrations among probiotic treatments. The blood testosterone concentrations in ZADO and YEAST supplemented groups were significantly higher than that in the control group. IgA concentration was significantly increased in buck rabbits fed SP, ZADO and YEAST treatments compared with the control group. Indeed, IgG and IgM were increased (P<0.05) in the buck rabbits fed YEAST compared with the control group. Reaction time was significantly shortest in the bucks fed microalgae and probiotic treatments compared to the control rabbits, However, fertility rate was higher (P<0.05) in the bucks fed ZADO and YEAST compared to the control group. All physical semen characteristics were significantly improved in the buck rabbits fed SP, ZADO and YEAST compared to the bucks in the control group. In conclusion, under hot conditions, supplementation of microalgae (SP) and probiotics (ZADO and YEAST) at the level of 1 % to the buck Hi-Plus rabbit’s diets is a simple, safe and practical method for decreasing the heat stress effects, improving buck reproductive performance and physical semen characteristics.