Improved gonadal sperm reserves, growth performance, and antioxidant capacity of maturity V-line rabbits fed Vespa oriental meal

Insects continue to receive considerable interest as a potential nutrient source and as nutraceuticals. In this study, the effects of diets containing 25 and 50% of Vespa orientalis meal (VOM) as a replacement for soybean meal (control: 100%), on the reproductive potential of 90-day-old V-line male rabbits (average weight: 1.06 +/- 0.03 kg) were investigated. Bucks fed the 50% VOM diet demonstrated the highest increase in body weight, reaction time, and testicular weight at maturity, and their gonadal sperm reserves (GSR) increased significantly (P<0.001) compared with those of other experimental groups. GSR in the testis was significantly (P<0.001) higher in rabbits fed a diet containing VOM than the control group. Epididymal sperm reserves in caput, corpus, and cauda increased significantly (P<0.001) as the percentage of VOM increased in the diets of bucks. The daily sperm production per gram in the testis of bucks fed with diets containing VOM improved significantly (P<0.05; by 39.67 and 62.13% when provided with diets containing 25 and 50% VOM, respectively) compared with that in the control group. Similarly, testosterone and follicle-stimulating hormone levels were significantly (P<0.05) higher in the VOM-fed groups than in the control group. However, luteinising hormone levels declined (P<0.05) in the VOM- provided groups than in the control group. Supplementation with different VOM levels significantly (P<0.001) enhanced the serum total antioxidant capacity, and glutathione peroxidase and superoxide dismutase activities, and decreased the serum malondialdehyde levels compared with the control group. Serum biochemical traits, including protein and lipid profiles and glucose concentration, were significantly improved in bucks fed with VOM- supplemented diets. In conclusion, dietary VOM supplementation promotes the daily sperm production, testicular sperm reserves, sexual hormone production, and antioxidant capacity of V-line bucks.