An economic analysis of beef stocking rates.
ABSTRACT The Land Conversion Scheme and the prevailing maize and meat market situations have given rise to renewed interest in livestock production from cultivated pasture. The model developed by Jones and Sandland (1974) is used to determine optimum stocking rates under various circumstances. A micro-computer model, OPTSR, is developed for relatively quick solutions.
The relation between animal gain and stocking rate in grazing trials: an examination of published theoretical models
SUMMARY Jones & Sandland (1974) examined the validity of the linear model for gain per animal on stocking rate. This paper examines the alternative models of Conniffe, Browne & Walsh (1970, 1972) and a proposed extension of the model of Owen & Ridgman (1968). Discrepancies between these models and the linear model are studied in detail. Under specified conditions these models are shown to be very close to the linear model. It is concluded, from the earlier work of Jones & Sandland (1974) and these results, that the empirically justified simple linear model has the advantage of being much easier to fit as well as embodying (approximately) the theoretical advantages of these conceptually superior models under a range of assumptions.
Effects of soils, fertilizers and stocking rates on pastures and beef production on the Wallum of south-eastern Queensland. 2. Liveweight change and beef production
Animal production was measured over a six-year period from grass-legume pastures receiving different maintenance rates of phosphorus and potassium fertilizers, and continuously grazed at stocking rates of 1.23, 1.65 and 2.47 beasts ha-1. The pastures consisted of the grasses Chloris gayana, Digitaria decumbens, Paspalum dilatatum and P. commersonii and the legumes Desmodium intortum, D. uncinatum, L otononis bainesii, Macrop tilium lath yroides and Trifolium repens. Annual applications of 250 kg ha-1 superphosphate (9.6 per cent P) significantly increased animal production above applications of 125 kg ha-1 superphosphate, but there were no significant effects of increase in level of applied potassium (as KCI) beyond 63 kg ha-1. The greatest liveweight gain per hectare was obtained at a stocking rate of 2.47 beasts ha-1 but rate of liveweight change was more variable than at the other stocking rates. Conversely, daily liveweight gains per head and rate of turnoff were greatest at 1.23 beasts ha-1. Both stocking rates and levels of superphosphate affected quality of carcase produced, and there was a significant positive correlation of liveweight gain and legume content of the pastures.