1Ball P J H,Peters A R.Reproduction in cattle[M].Blackwell Publishing,2004,8:92-100.
2Firk R,Stamer E,Junge W,et al.Automation of oestrus detection in dairy cows:a view[J] Livestock Production Science,2002,75:219-232.
3Lopez H,Satter L D,Wiltbank M C.A brief report on the relationship between level of milk production and estrous behavior of lactating dairy cows[J].Animal Reproduction Science,2004,88:359-363.
4Cavalieri J,Flinker L R,Anderson G A,et al.Characteristics of oestrus measured using visual observation and radiotelemetry[J].Animal Reproduction Science,2003,76:1-12.
5Roelofsa J B,Bouwmana E G,Dielemanb S J.Influence of repeated rectal ultrasound examinations on hormone profiles and behaviour around oestrus and ovulation in dairy cattle[J].Theriogenology,2004,62:1337-1352.
6Roelofs J B,van Eerdenburg F J,Soede N M,et al.Various behavioral signs of estrous and their relationship with time of ovulation in dairy cattle Theriogenology,2005,63 (5):1366-1377.
7Pranee R,Gordon K,Sahattaya S,et al.Oestrous behavior of Holstein cows during cooler and hotter tropical seasons[J].Animal Reproduction Science,1996,45:47-48.
8Van Vliet J H,Van Eerdenburg F J.Sexual activities and oestrus detection in lactation Holstein cows[J].A pplied Reproduction Science,1996,50:57-69.
9Van Eerdenburg F J,Loeffler S H,Van Vliet J H.De tection of oestrus in dairy cows:a new approach to an old problem[J].Vet Quart,1996,18:52-54.
10Van Eerdenburg F J,Karthaus D,Taverne M A,Merics I,Szenci O.The relationship between estrous behavioral score and time of ovulation in dairy cattle[J].Dairy Science,2002,85(5):1150-1156.