The effect of l-arginine and flaxseed on plasma testosterone concentration, semen quality and some testicular histology parameters in old broiler breeder roosters.

The objective of this study was to investigate the effect of dietary supplementation of l-arginine and flaxseed on testosterone and lipid parameters of serum and semen quality, as well as histological and morphometric parameters of testes in old broiler breeder rooster. Thirty six 52-week-old Ross 308 broiler breeder roosters with similar weights (4900 g ±â€¯210) were used for a 8-weeks trial period in a 3 × 3 factorial arrangement of dietary treatments that three levels of l-arginine (0.52, 0.68 and 0.83%) and flaxseed (0, 2 and 4%) with four replications in each. The ratio of left testicle weight/total testicular weight was significantly higher in A68F0 group. The maximum and minimum seminiferous tubule diameters were recorded for roosters fed no flaxseed and F2 flaxseed, respectively. The roosters fed A68 showed the highest serum testosterone. Seminal volume and sperm concentration, were not significantly affected by l-arginine × flaxseed interaction; however, sperm forward motility were significantly affected by arginine × flaxseed interaction (P < 0.05). A68F0 had significantly greatest tubular differentiation indices (TDI) in all of the treatments. Also, repopulation indices (RI) and spermiogenesis indices (SI) in A68F0 were significantly higher than other groups, but A52F0 and A52F4. However, testis index, testis density, serum lipids (cholesterol, LDL, HDL and HDL: LDL ratio), epithelium height of seminiferous tubules and number of Sertoli cells were not affected by the treatments. It is concluded that dietary supplementation of arginine (0.68%) has positive effects on blood testosterone, semen quality and spermatogenesis index of aged roosters.