@conference {40906,
	title = {Methane emission from grazing sheep and cattle},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {57},
	year = {1997},
	month = {Jan},
	pages = {130-133},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {Measurements of methane emissions from individual sheep and dairy cows grazing typical New Zealand perennial ryegrass/white clover dominant pastures are reported. These are the first measurements reported from grazing sheep, and among the first from grazing cattle. The measurement technique, using a marker gas (sulphur hexafluoride), enables emission rates to be determined from analyses of "breath" samples collected while grazing. More than 250 measurements of daily methane emission from 50 sheep (8 months old) were made, with flock-mean emission 18.9{\textpm}0.8 g/d. Emissions were weakly correlated with feed intake, and they represented a 4.6{\textpm}0.1\% average loss of gross dietary energy. The corresponding mean emission based on 40 measurements of daily emissions from 10 lactating dairy cows was 263{\textpm}10 g/d, approximately 6.2\% of estimated gross energy intake. A notable feature was the large inter-sheep variability in daily methane emission (range 140\%) that could not be attributed to variable intake. This would appear to suggest an appreciable diversity of methanogenic response to digestion, and may be significant in the search for strategies to control emissions of this greenhouse gas. },
	issn = {1176-5283},
	author = {Ulyatt MJ and Lassey KR and Martin RJ and Walker CF and Shelton ID}
}
@conference {40277,
	title = {Impact of potential change in climate and atmospheric concentration of carbon dioxide on pasture and animal production in New Zealand},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {51},
	year = {1991},
	month = {Jan},
	pages = {25-33},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {Three groups of 10 ewes each were treated with Repromap sponges  (MAP), Chronogest sponges (FGA) or Controlled Drug Release devices  (CIDR) for 11 days. At withdrawal the delay time until oestrus, LH  surge and ovulation was measured.   There was no significant difference between the two sponge treatments in  mean delay times although FGA treated ewes tended to be less variable in  their activity.   CIDR treated ewes commenced standing oestrus sooner than MAP and FGA  treated ewes (30h vs 42h and 40h respectively P<0.001). Similarly the  onset of the LH surge (31h vs 46h and 46h P<0.001) and ovulation (59h vs  69h and 71h P<0.001) occurred sooner in the CIDR ewes compared to MAP  and FGA sponges.  },
	issn = {1176-5283},
	author = {Martin RJ and Korte CJ and McCall DG and Baird DB and Newton PCD and Barlow ND}
}
