References
- Macmillan , KL and Peterson , AJ . 1993 . A new intravaginal progesterone releasing device for cattle (CIDR-B) for oestrous synchronisation, increasing pregnancy rates and the treatment of post-partum anoestrus . Animal Remoduction Science , 33 : 1 – 25 .
- Macmillan , KL , Taufa , VK and Day , AM . 1993 . Combination treatments for synchronising oestrus in dairy heifers . Proceedings of the New Zealand Society of Animal Production , 53 : 267 – 270 .
- Cliff , SC , Morris , GR , Hook , IS and Macmillan , KL . 1995 . Calving patterns in dairy heifers following single set-time inseminations and re-synchrony preceding second inseminations . Proceedings of the New Zealand Society of Animal Production , 55 : 70 – 71 .
- Xu , ZZ and Burton , LJ . 1999 . Reproductive performance of dairy heifers after estrus synchronization and fixed-time artificial insemination . Journal of Dairy Science , 82 : 910 – 917 .
- SAS Institute Inc. , ed. 1989 . SAS/STAT® User's Guide, Version 6 , Cary : SAS Institute Inc. .
- Grosshans , T , Xu , ZZ , Burton , LJ , Johnson , DL and Macmillan , KL . 1997 . Performance and genetic parameters for fertility of seasonal dairy cows in New Zealand . Livestock Production Science , 51 : 41 – 51 .
- Vishwanath , R , Nebel , RL , McMillan , WH , Pitt , CJ and Macmillan , KL . 1997 . Selected times of insemination with microencausulated bovine spermatozoa affect pregnancy rates of synchroiized heifers . Theriogenology , 48 : 369 – 376 .
- Savio , JD , Thatcher , WW , Morris , GR , Entwistle , K , Drost , M and Mattiacci , MR . 77-84 1993 . Effects of induction of low plasma progesterone . concentrations with a progesterone-releasing intravaginal device on follicular turnover and fertility in cattle , Journal of Reproduction and Fertility : 98 – 98 .
- Sirois , J and Fortune , JE . 1990 . Lengthening the bovine estrous cycle with low levels of exogenous progesterone: A model for studying ovarian follicular dominance . Endocrinology , 127 : 916 – 925 .
- Stock , AE and Fortune , JE . 1993 . Ovarian follicular dominance in cattle: Relationship between prolonged growth of the ovulatory follicle and endocrine parameters . Endocrinology , 132 : 1108 – 1114 .
- Mihm , M , Baguisi , A , Boland , MP and Roche , JF . 1994 . Association between the duration of dominance of the ovulatory follicle and pregnancy rate in beef heifers . Journal of Reproduction and Fertility , 102 : 123 – 130 .
- Sawyer , GJ , Broadbent , PJ and Dolman , DE . 1995 . Ultrasound-monitored ovarian responses in normal and superovulated cattle given exogenous progesterone at different stages of the oestrous cycle . Animal Reproduction Science , 38 : 187 – 201 .
- Xu , ZZ , Burton , LJ and Macmillan , KL . 1996 . Reproductive performance of actating dairy cows following oestrus synchronisation with progesterone, oestradiol and prostaglandin . New Zealand Veterinary Journal , 44 : 99 – 104 .
- Burke , CR , Boland , MP and Macmillan , KL . 1999 . Ovarian responses to progesterone and oestradiol benzoate administered intravaginally during dioestrus in cattle . Animal Reproduction Science , 55 : 23 – 33 .
- Macmillan , KL and Taufa , VK . 1997 . Oestradiol concentrates the synchrony pattern in heifers treated with progesterone and prostaglandin F2α . Proceedings of the New Zealand Society of Animal Production , 57 : 238 – 238 .
- Hanlon , DW , Williamson , NB , Steffert , IJ , Wichtel , JJ and Pfeiffer , DU . 1997 . Re-insertion of the CIDR progesterone-containine intravaeinal device to synchronise returns to oestrus in dairy heifers . New Zealand Veterinary Journal , 45 : 15 – 18 .
- Van Cleeff , J , Macmillan , KL , Drost , M , Lucy , MC and Thatcher , WW . 1996 . Effects of administering progesterone at selected intervals after insemination of synchronized heifers on pregnancy rates and resynchronization of returns to service . Theriogenology , 46 : 1117 – 11130 .
- Macmillan , KL , Taufa , VK and Day , AM . 1997 . Manipulating ovarian follicle wave patterns can partially synchronise returns to service and increases the pregnancy rate to second inseminati.0.n . Proceedings of the New Zealand Society of Animal Production , 57 : 237 – 237 .
- Rendel , JM , Xu , ZZ and Burton , LJ . 1998 . Artificial insemination of yearling heifers: An economic analysis , 259 – 262 . Rotorua : Proceedings of theDairy Cattle Session of the 15th Annual Seminar of the Society of Dairy Cattle Veterinarians of the New Zealand Veterinary Association .