Expression of pregnancy-specific beta-1-glycoprotein, aromatase and nitric oxide synthase in bovine sperm

Abstract

In search of alternative indicators of fertility in bulls, this research evaluated the effects of breed, type of cattle and age on the relative expression of the genes aromatase, pregnancy-specific beta-1-glycoprotein (PSG1), and nitric oxide synthase (NOS) In bovine semen. Sperm from Jersey, Holstein. Brahman, Brangus, Charolais, Charbray, Senepol, and Simmental bulls was collected and the extracted mRNA was analyzed for expression of the genes using real time polimerase chain reaction (RT-PCR). The relative expression of aromatase was lower (P 0.07) In sperm from Jersey bulls (0.89) than in bulls of all other breeds (average 1.01). The relative expression of PGS1 was greater (P 0.02) in sperm from dairy (1.00) than from beef bulls (0.96). Age did not affect relative expression of the genes under study. Additionally, in data from 31 bulls, expression of NOS was positively correlated with scrotal circumference (r = 0.31; P 0.08). As far as we know, these are the first results showing that the genes aromatase, PSG1 and NOS can be detected in bull sperm and may have implications as molecular markers for bull fertility.