@conference {40417,
	title = {A modelling study of the productivity and profitability of unmated and mated ewes on North Island hill country},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {52},
	year = {1992},
	month = {Jan},
	pages = {221-224},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {Five groups (15-30) of Romney or Merino ewes were synchronised  with CIDR devices for 12 days in March or April. In all but one group  of Romney ewes 400IU PMSG was injected at CIDR removal. Intervals to  onset of oestrus and ovulation were determined by recording crayon marks  and laparoscopy respectively every 4 hours. Interval to ovulation was  not affected by ewe breed or month of treatment, but it was 7.9 hours  earlier in ewes injected with PMSG (48.9h vs 56.8h P<0.001) and the  variance was less (13.4h vs 35.7h P<0.05). Interval to oestrus was  affected by breed of ewe, date of synchronisation and use of PMSG.  },
	issn = {1176-5283},
	author = {Parker WJ and Gray DI and Morris ST and McCutcheon SN}
}
