@conference {40418,
	title = {Comparative performance of ewes shorn either once-yearly or 3 times in 2 years},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {52},
	year = {1992},
	month = {Jan},
	pages = {225-228},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {The determinants of wool production per unit area of skin are  reviewed, and found to be dominated by follicle volume. Evidence is  presented to show that follicle cells destined to become fibre cells  differentiate into a continuum of cell types rather than discrete  populations of medullary, ortho- and paracortical cells as the  literature suggests. Fibres of the same dimensions grown by a sheep at  one point in time contain differing proportions of these cell types. It  is hypothesised that there is a degree of independence between fibre  volume and cell differentiation. Medulla formation is explained in  terms of competition between follicles for keratin precursors, so that  fibre volume exceeds the available volume of keratin. A similar  mechanism is proposed for the cortex, where paracortex and mesocortex  become less prevalent as total fibre volume increases. It is concluded  that a model for fibre formation can be considered in two parts: one  which generates fibre volume and another which determines cell type  within that volume.  },
	issn = {1176-5283},
	author = {Sumner RMW and Webby RW and Winter RD}
}
@conference {39896,
	title = {Spring-summer grazing management on hill country: effects on ewe performance},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {44},
	year = {1984},
	month = {Jan},
	pages = {117-120},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {The soil type is an important factor influencing the occurrence of trace element deficiencies in grazing animals in New Zealand. Cobalt and selenium deficiencies occur mainly on soils from acidic rocks. Cobalt deficiencies may also occur on soils from more basic parent materials where the soils have been strongly leached. Selenium deficiencies is less easily predicted on the basis of soil characteristics. Copper deficiencies are more likely in stock grazing on peat soils, gley soils, certain pumice soils, saline soils, recent soils and some steepland soils. For all 3 elements, classification of occurrences of deficiency by soil type has provided a basis for delineating areas where deficiencies are likely, areas where they are unlikely and areas of marginal status. This has enabled a rational approach to investigations and the application of treatment and control measures.},
	issn = {1176-5283},
	author = {Smeaton DC and Wadams TK and MacKisack BD and Winter RD and Miller CM and Hockey H-UP}
}
