EFFECTS OF INHIBIN-α AND ANTI-INHIBIN-α IMMUNIZATION ON THE REPRODUCTIVE HORMONES IN KAZAKH SHEEP

The Kazakh sheep is native to China. The breed has many advantages, including its size, hardiness, and good meat production, it has the economic disadvantage of having a low reproductive rate. Inhibin-alpha (INH alpha) regulates the synthesis and secretion of follicle-stimulating hormone (FSH) and could feasibly be used to boost reproduction in the Kazakh sheep. However, the current methods of INH alpha preparation are both costly and time-consuming. Here, we investigated the effects of INH alpha on Kazakh sheep reproductive performance by immunization with INH alpha and analyzing the subsequent changes in reproductive hormone levels and blood biochemical indices. An anti-INH alpha polyclonal antibody was raised in camel. It and a recombinant INH alpha protein were used to immunize groups of adult Kazakh sheep in anestrus. Reproductive hormones (FSH, luteinizing hormone [LH], progesterone [P-4], and estradiol [E-2]) were measured by ELISA, together with the measurement of changes in INH levels and blood physiological and biochemical indicators. The blood levels of LH and P-4 in the sheep immunized with the camel anti-INH alpha polyclonal antibody (group A) did not differ significantly from those in the recombinant INHa protein (group B) and the control group (group C) ( P >0.05). FSH and E-2 levels in group A were significantly higher than the controls (P <0.05) and the INH concentrations were significantly lower than those in group C (P <0.05). There were no abnormalities in the blood biochemical indices in groups A, B, and C.In conclusion, immune INHa preparations significantly affected the blood reproductive hormone levels of Kazakh sheep. This technique has potential application for improving the reproductive performance in these sheep and is also relevant for future research into the development of an INH alpha vaccine.