6[1]MagashA.Theuseofbiotechniques inyak reproduction[A].Proceedingsof thesecondinternational congress on yak[C].Xining,China:Qinghai People's Publishing House,1997.175-178.
7[3]YunZ.Experiment on estrus synchronization for artificial inseminationwith frozen semen in yak[A].Proceedings of the third intemationalcongress on yak[C].Addis Ababa,Ethiopia:International Livestock Research Institute,2000.349-352.
9Segwagwe B V E. The Effect of GnRH or oestradiol benzoate on follicular dynamics and ovulation as well as the treatment of postpartum anoestrus in Holstein cows [ D]. M V Sc Thesis, University of Melbourne, 2002.
10PancarciS M, Jordan E R, Risco C A. Use of estradiol cypionate in a pre-sychronized timed artificial insemination program for lactating dairy cattle [ J]. J Dairy Sci, 2002, (85): 122-131.
