Abstract:
ECONOMICS OF SELECTION FOR FLEECE TYPE IN ARID ZONES P. R. McMAHON* Summary The presence of dust and/or burr limits the style classification used in valuing wool to types where no premium is paid for length and virtually no premium for character. The implications of these facts in selecting rams and culling stock are outlined. Suggestions for improved techniques are made. I. INTRODUCTION Financial returns from wool are affected by weight and price per pound; the latter is determined by fibre fineness, fibre length, style, colour, degree of contamination by dust and vegetable matter, and by the influence of weather during growth (Skinner 196 1) . Analyses of market prices have emphasised the importance of fibre fineness in terms of the value of clean scoured product, and the relative unimportance of other factors, especially in arid zone wools (Paynter 1964). The 'style grade' (Henderson 1968), for example, of such wools is usually limited by the presence of dust and vegetable matter, and no amount of selective breeding or culling will lift this wool above the 'good topmaking' category. The fact that, for these types, there is little premium for style or length is not clearly understood by many wool growers who tend, as a result, to make culling and ram selection decisions inefficiently. II. DATA USED Clean prices for wools of different style for the 1967/68 season from the Australian Wool Board's Statistical Service data in Table 1 show that in these types there is little premium for style. Similarly, length has little influence on clean price, as shown in Table 2 for Best, Good and Average Topmaking styles. Length, however, makes a strong contribution to fleece weight and, if fleece weight is not being measured directly, length for quality is probably the most important basis for sheep classing. * School of Wool and Pastoral Sciences The University of New South Wales, Sydney, New South Wales. 136 TABLE 1 TABLE 2 Wool prices in cents per lb clean 1967-68 season Table 3, by comparison, shows average prices for the 1967/68 season for north western type wools from N.S.W. in the Best, Good and Average Topmaking styles, which demonstrate a difference between 70's, 64's and 60's of approximately 22 cents/kg (10 cents/lb) clean per quality number. These figures have been used to calculate break-even points for the relationship between quality number and fleece weight as shown in Table 4. TABLE 3 137 TABLE 4 III. CONCLUSIONS Rangeland maintenance requires a conservative stocking policy with the result that arid zone sheep normally have surplus feed available. Heavy fleece weight in these circumstances takes on even greater importance because it has been established that sheep with heavy fleeces are more efficient as converters of feed into fleece (Turner and Young 1969). On the other hand, little economic value can be attached to fleece characters which are traditionally regarded as all-important by the wool trade and which may, however, be of more significance away from the arid zone environment (McMahon 1970). Wasteful sheep culing practices are used by many large wool growers and the advantages of culling on the basis of fleece weight among young sheep are almost entirely neglected despite a probable benefit of roughly one extra bale of wool per thousand ewes (C.S.I.R.O. 1955). Similarly, production improvement programmes based on measurement are used to a very limited extent by leading studmasters. Use of these methods has been demonstrated to give cumulative gains in productivity exceeding 2 per cent per year (Turner and Young 1969)) the original techniques being emphasised as early as 1943 for Romney Marsh sheep in New Zealand (McMahon 1943). Finally, it is worth drawing attention to differences which are likely to exist between strains and studs within the Merino breed (Jackson and Roberts 1970). If the sheep industry is to survive in difficult and more arid environments in the face of production costs determined by Australian prosperity and prices fixed by world markets, it should exploit all avenues of increased production including the sort of production increases which metrology and recording have given to the dairy industry in New Zealand, to the pig industry in Denmark and . to the poultry industry throughout the world. IV. ACKNOWLEDGMENT Thanks are due to Mr. J. R. Paynter for analysis of the Australian Wool Board's Statistical Service data. 138 V. 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