Effect of Tribulus trrestris herb on sex ratio of sperm in Arabic Khozestan ram by real time-qPCR technique.

The present study was conducted to evaluate the effect of Tribulus Tresstrise (TT) herb on sex ratio of semen in Arabic Khouzestan ram using real time-qPCR technique using 18 rams in a completely randomized design with 3 treatments. The SRY and PLP genes were amplified to isolate the specific fragments of Y- and X- chromosome sequences. The treatments included: i) the control group (0% TT), ii) Diet containing 15 g/kg TT, iii) Diet containing 30 g/kg TT. Sperm sampling was taken from all rams at 10 month of age and blood sampling was performed at 8 and 10 month of age. The results showed that expression rate of SRY gene increased with increasing TT level and rams that received 30 g/kg TT diet had the highest SRY gene expression and PLP gene expression decreased with increasing TT level (p-value =0.004). There was positive correlation between Testosterone concentration and SRY gene expression at 8 (0.65) and 10 (0.59) month of age, and the relationship between PLP gene expression and Testosterone concentration was negative and -0.61 and -0.66 at 8 and 10 month of age, respectively (p-value= 0.006). The results indicated that adding Tribulus Tresstrise herb to the ram diet increases the SRY gene expression and also sperm containing Y chromosome. In other words, it increases the sex ratio toward male gens in Arabic Khozestan ram by increasing the androgen hormones.