Chinese Erhualian and Meishan pigs are two subpopulations of Chinese Taihu pigs and known for prolificacy (Cheng 1983), whose boars have higher levels of circulating FSH, LH and androgens, but relatively smaller testes, less seminiferous tubules and Sertoli cells per gram of the testicular tissue, and lower total daily sperm production and ejaculate volume compared with Western commercial breeds (Wise et al. 1996; Lunstra et al. 1997). Chinese Erhualian or Meishan boars have become a valuable genetic resource to decipher the physiological and genetic mechanisms for the male reproductive performance.