2POLGE C. Artificial insemination inpigs[J].Vet Pec, 1956 (68) :62-76.
3ABEYDEEAR L R’DAY B N.Fertilizationand subsequent development in vitro ofpig oocytes inseminated in a modifiedTris-buffered medium with frozen-thawed ejaculated spermatozoa[J]. BiolReprod,1997 (57) :729-734.
4FAHY G M. Effect of rapid warmingof boar semen on sperm morphologyand physiology[J]. Cryobiology, 1986(23):1-13.