@conference {41770,
	title = {Evaluation of the sulphur hexafluoride tracer technique for methane emission measurement in forage-fed sheep},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {67},
	year = {2007},
	month = {Jan},
	pages = {431-435},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Wanaka},
	abstract = {The aim of this study was to evaluate the sulphur hexafluoride (SF6) tracer technique for methane (CH4) emission measurement in sheep. Methane emissions from ten Romney sheep were individually measured both by the SF6tracer ({\textquoteleft}tracer CH4{\textquoteright}) and by the indirect calorimetry chamber ({\textquoteleft}calorimetric CH4{\textquoteright}) techniques while fed on lucerne hay. The tracer technique involved the use of permeation tubes with pre-calibrated permeation rates ({\textquoteleft}pre-calibrated PR{\textquoteright}) of SF6. The {\textquoteleft}tracer CH4{\textquoteright} measurements were carried out for 5 days in digestibility crates housed within a covered yard. Sheep were transferred to calorimetry chambers for 3 days acclimatisation, followed by measurement of CH4emission for 3 days. Permeation tubes were recovered at the end of the animal trial and their {\textquoteleft}post-recovery PR{\textquoteright} determined after subsequent weighing for a 6-month period. Although the {\textquoteleft}tracer CH4{\textquoteright} was slightly lower (by 4\%) and had larger variation than the {\textquoteleft}calorimetric CH4{\textquoteright} values (18.8{\textpm}0.4 vs. 19.5{\textpm}0.6), the two measurement techniques did not differ significantly (P>0.05) in their CH4emission estimates. The {\textquoteleft}post-recovery PR{\textquoteright} was not different (P>0.05) from their {\textquoteleft}pre-calibrated PR{\textquoteright} values, and they were highly correlated to each other (r=0.98, P<0.0001). It is concluded that the tracer technique provides a reliablealternative method for CH4measurement in forage-fed sheep.},
	issn = {1176-5283},
	author = {Pinares-Patino CS and Holmes CW and Lassey KR and Ulyatt MJ}
}
@conference {41235,
	title = {Early indications that feeding Lotus will reduce methane emissions from ruminants},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {61},
	year = {2001},
	month = {Jan},
	pages = {23-26},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Christchurch},
	abstract = {Ruminant livestock produce at least 75\% of New Zealand{\textquoteright}s total methane emissions and are a major contributor of greenhouse gas emissions. Most ruminant methane arises from microbial activity in the rumen (methanogenesis) and is released through the mouth and nose. Methane production per unit feed intake or per unit production can be reduced by improving diet quality, for example, including legumes in a pasture diet. A preliminary investigation with wether sheep showed lower daily methane outputs per unit dry matter intake (DMI) when fed Lotus pedunculatus (a condensed tannin-containing legume) than ryegrass-based pasture or lucerne (14.5 vs. 20.4 vs. 19.0 gCH4/kg DMI). Friesian dairy cows fed either Lotus corniculatus silage or perennial ryegrass silage had similar total methane outputs (376.7 vs. 344.4 g CH4/cow/day; ns). However, methane emissions were lower from cows fed Lotus silage when expressed per unit DMI (26.90 vs. 35.13 g CH4/kg DMI; P<0.001) and per unit production (378 vs. 434 g CH4/kg milksolids; P<0.05) as a result of the higher intake and milksolids yield. The mitigation of methane emissions from animals fed Lotus species was due in part to a higher nutritive value relative to pasture but effects of condensed tannins on methanogenesis warrants further investigation. },
	issn = {1176-5283},
	author = {Woodward SL and Waghorn GC and Ulyatt MJ and Lassey KR}
}
@conference {40872,
	title = {Can protein utilisation from pasture be improved?},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {57},
	year = {1997},
	month = {Jan},
	pages = {4-8},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {Although temperature pasture plants usually contain sufficient protein to potentially support most types of animal production, this protein is utilised for ruminant production with relatively low efficiency because of the losses that occur via microbial deamination in the rumen.  These processes are well understood, yet procedures that should theoretically improve protein capture, such as the addition of soluble carbohydrate or protected protein to the diet, are frequently not effective.  The paper considers reasons for this situation.  It also examines several additional reasons why plant protein utilisation may be impaired, such as high rumen degradability, hepatic detoxification of absorbed ammonia and its associated costs in terms of amino acid catabolism, and the relationship between amino acid supply to the duodenum and tissue amino acid requirements. The paper evaluates whether an enhanced supply of individual amino acids, or mixtures of amino acids, to the tissues might increase the production of meat, milk and wool.  It also considers whether we have enough information to be able to assess the likelihood of using specific enhanced amino acid supply or novel combinations to manipulate product quality. The efficacy of various mathematical models of protein digestion and metabolism are evaluated in relation to our current knowledge of the subject. },
	issn = {1176-5283},
	author = {Ulyatt MJ}
}
@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 {40797,
	title = {The metabolic cost of hepatic ammonia detoxification},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {56},
	year = {1996},
	month = {Jan},
	pages = {130-132},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {The quantity of ammonia removed from portal blood by the ovine  liver was measured using four sheep prepared with in-dwelling catheters in  the hepatic region and fed either lucerne pellets (L) or white clover (WC) at  900 gDM/day. Following blood sampling, plasma ammonia and oxygen  concentrations were determined. The portal ammonia concentration and  flow were significantly (P<0.01) affected by the diet (304 and 646 },
	issn = {1176-5283},
	author = {Greaney KB and Reynolds GW and Ulyatt MJ and MacKenzie DDS and Harris PM}
}
@conference {40042,
	title = {Importance of dry matter content to voluntary intake of fresh grass forages},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {47},
	year = {1987},
	month = {Jan},
	pages = {13-16},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {The data from 2 series of trials were used to examine the effects of variation in leaf, green and total allowance on the herbage intake and milk production of dairy cows and the liveweight gain of weaned lambs over late spring and summer. Both the herbage intake and milk production of dairy cows and the liveweight gain of lambs were better related to leaf allowance than to green or total herbage allowance. With lambs, however, there were differences in liveweight gain at similar leaf allowances between experimental periods. These were largely accounted for by the percentage of dead herbage in the pasture. It is suggested that differences in animal performance over late spring and summer may be influenced by the level of leaf mass and dead matter in pasture but not the level of green grass stem.},
	issn = {1176-5283},
	author = {John A and Ulyatt MJ}
}
@conference {39797,
	title = {Effects of chewing during eating on particle size reduction and subsequent fermentation in sheep},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {42},
	year = {1982},
	month = {Jan},
	pages = {159-160},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {No abstract supplied},
	issn = {1176-5283},
	author = {Ulyatt MJ and Reid CSW and Carr DH}
}
@conference {39726,
	title = {The nutrients available to grazing cattle - Brief Communication},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {41},
	year = {1981},
	month = {Jan},
	pages = {140-141},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	issn = {1176-5283},
	author = {Ulyatt MJ and Beever DE and Thomson DJ}
}
@conference {39689,
	title = {Factors influencing nitrogen flow from the rumen},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {40},
	year = {1980},
	month = {Jan},
	pages = {226},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	issn = {1176-5283},
	author = {John A and Ulyatt MJ and Jones WT and Shelton ID}
}
@conference {39560,
	title = {The physical breakdown of feed during digestion in the rumen},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {37},
	year = {1977},
	month = {Jan},
	pages = {173-175},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	issn = {1176-5283},
	author = {Reid CSW and Ulyatt MJ and Monro JA}
}
@conference {39516,
	title = {The basis of nutritive value - a modelling approach},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {36},
	year = {1976},
	month = {Jan},
	pages = {140-149},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	issn = {1176-5283},
	author = {Ulyatt MJ and Baldwin RL and Koong LJ}
}
@conference {39426,
	title = {Plant tannins, bloat and nutritive value},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {34},
	year = {1974},
	month = {Jan},
	pages = {82-93},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	issn = {1176-5283},
	author = {Reid CSW and Ulyatt MJ and Wilson JM}
}
@conference {39394,
	title = {Quantitative Aspects of Fermentation in the Gastro-Intestinal Tract of Sheep Fed Fresh Herbage},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {33},
	year = {1973},
	month = {Jan},
	pages = {149-156},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	issn = {1176-5283},
	author = {Ulyatt MJ and Dellow DW and Egan AR and Walker DJ}
}
@conference {39361,
	title = {Influence of Experimental Design in Measuring the Voluntary Intake of Grazing Sheep},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {32},
	year = {1972},
	month = {Jan},
	pages = {85-86},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	issn = {1176-5283},
	author = {Ulyatt MJ}
}
@conference {39330,
	title = {The Sites of Digestion of Fresh Pasture Species in the Gastro-Intestinal Tracts of Sheep},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {31},
	year = {1971},
	month = {Jan},
	pages = {74-81},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	issn = {1176-5283},
	author = {Ulyatt MJ and MacRae JC}
}
@conference {39301,
	title = {The nutritive value of the residue from protein-extracted herbage},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {30},
	year = {1970},
	month = {Jan},
	pages = {92-93},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	issn = {1176-5283},
	author = {Ulyatt MJ}
}
@conference {39300,
	title = {The production of volatile fatty acids in sheep on different pasture types},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {30},
	year = {1970},
	month = {Jan},
	pages = {90-91},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	issn = {1176-5283},
	author = {Mackintosh JB and Ulyatt MJ}
}
@conference {39273,
	title = {Progress in defining the differences in nutritive value to sheep of Perennial Ryegrass, Short-Rotation Ryegrass and White Clover},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {29},
	year = {1969},
	month = {Jan},
	pages = {114-123},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	issn = {1176-5283},
	author = {Ulyatt MJ}
}
@conference {39234,
	title = {The use of steady state feeding system in nutrition experiments with ruminants},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {27},
	year = {1967},
	month = {Jan},
	pages = {181-192},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	issn = {1176-5283},
	author = {Ulyatt MJ}
}
@conference {39171,
	title = {Studies on some factors influencing food intake in sheep},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {24},
	year = {1964},
	month = {Jan},
	pages = {43-56},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	issn = {1176-5283},
	author = {Ulyatt MJ}
}
