Effect of high doses of α-tocopherol acetate on testicular morphology and histology parameters in broiler breeder roosters

The aim of this study was to investigate effect of dietary supplementation by high doses of α-tocopherol acetate breeder (20 weeks of age) were used in two groups, standard (n=30; body weight= 3.109±0.169) and heavy (n=30; ±body weight= 3509±0.161) weight. Roosters were individually kept and randomly divided into 10 treatments (in a 2×5 factorial arrangements with six replicates in each group). The experimental treatments were fed a same diet supplemented with different levels of vitamin E (0, 100, 200, 300, 400 mg α-tocopherol acetate/kg diet) for 10 weeks. The heavy weight group received 30% excessive diet than standard group from beginning until the end of the experiment. After 5 weeks of adaptation period, roosters were fed by supplemented diet for 10 weeks. In the end of experiment roosters slaughtered and testicles removed from carcass for morphology and histology analysis. Results showed that vitamin E were significantly increased the size of testis, the number of seminiferous tubules in all treatment group compared to the control group (P ≤ 0.05). As well as, in two body weight groups the weight of testis, left testis diameter, seminiferous tubules diameter, seminiferous epithelium thickness, number of leydig cell and blood vessels were highest in E400 group (P ≤ 0.05). Finally, based on these results, it was concluded that high dose of vitamin E (400 mg/kg diet) improved testis morphology and histology parameters.