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Stocking intensity and pastoral production: III. Wool production, fleece characteristics, and the utilization of nutrients for maintenance and wool growth by Merino sheep grazed at different stocking rates

Published online by Cambridge University Press:  27 March 2009

J. P. Langlands  and
I. L. Bennett
J. P. Langlands
Affiliation:
C.S.I.R.O., Pastoral Research LaboratoryArmidale, N.S.W., 2350, Australia
I. L. Bennett
Affiliation:
C.S.I.R.O., Pastoral Research LaboratoryArmidale, N.S.W., 2350, Australia
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Summary

Wool production and wool characteristics are reported for a 5-year period in which sheep grazed Phalaris tuberosa–Trifolium repens pastures at stocking rates ranging from 2·5 to 37·1 sheep/ha. The utilization of nutrients for maintenance and wool production were calculated over shorter periods.

Maximum wool production/ha was always recorded at the highest stocking rate attained. The highest annual maximum was 111 kg clean wool/ha in 1963–4. The decline in wool production/sheep/unit increase in stocking rate was greatest during winter and the amplitude of the seasonal rhythm in wool production increased with stocking rate.

At high stocking rates wool count increased, staple length and character declined, colour and handle improved, soundness tended to decline and fibre entanglement (cotting) to increase particularly during drought. Live-weight gain/sheep also declined with stocking rate, the rate of decline being greatest during drought. Maximum live-weight change/ha was attained at a lower stocking rate than maximum wool production/ha.

The maintenance requirement of grazing sheep was estimated to be 58·3 kcal metabolizable energy/day/kg live weight and did not vary consistently with stocking rate. The value was 79% greater than the requirements for penned sheep estimated from fasting heat production.

Efficiency of wool production was defined as wool grown/100 g digestible organic matter intake (ED) and as wool grown/100 g nitrogen intake (EN). EN declined linearly with increasing stocking rate but the intercepts differed between months, and were least in late winter and early spring. En declined with stocking rate in winter and increased during summer. At low stocking rates, ED showed some variation throughout the year but this was much greater at high stocking rates.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 81 , Issue 2 , October 1973 , pp. 211 - 218
Copyright
Copyright © Cambridge University Press 1973

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References

Armstrong, D. G. (1964). Evaluation of artificially dried grass as a source of energy for sheep. II. The energy value of cocksfoot, timothy and two strains of rye-grass at varying stages of maturity. J. agric. Sci., Camb. 62, 399–416.CrossRefGoogle Scholar
Chapman, R. E. (1960). Measurement of wool samples. Appendix III in The Biology of the Fleece. Tech. Pap. Anim. Res. Labs. C.S.I.R.O. Aust. no. 3, pp. 97–107.Google Scholar
Chapman, R. E. & Wheeler, J. L. (1963). Dye-banding: A technique for fleece growth studies. Aust. J. Sci. 26, 53–4.Google Scholar
Coop, I. E. & Hill, M. K. (1962). The energy requirements of sheep for maintenance and gain. II. Grazing sheep. J. agric. Sci., Camb. 58, 187–99.CrossRefGoogle Scholar
Corbett, J. L., Langlands, J. P., McDonald, I. & Pullar, J. D. (1966). Comparison by direct animal calorimetry of the net energy values of an early and a late season growth of herbage. Anim. Prod. 8, 13–27.Google Scholar
Cowlishaw, S. J. (1969). The carrying capacity of pastures. J. Brit. Grassld Soc. 24, 207–14.CrossRefGoogle Scholar
Graham, N. McC. (1964). Utilization by fattening sheep of the energy and nitrogen in fresh herbage and in hay made from it. Aust. J. agric. Res. 15, 974–81.Google Scholar
Graham, N. McC. (1967). Net energy value of three subtropical forages. Aust. J. agric. Res. 18, 137–47.Google Scholar
Graham, N. McC. (1969). The net energy value of artificially dried subterranean clover harvested before flowering. Aust. J. agric. Res. 20, 365–73.Google Scholar
Hutchinson, J. C. D. & Wodzicka-Tomaszewska, M. (1961). Climate physiology of sheep. Anim. Breed Abstr. 29, 1–14.Google Scholar
Hutchinson, K. J. (1962). Climate corrections to the seasonal wool growth rhythm of sheep grazing in a southern Australian environment. Proc. Aust. Soc. Anim. Prod. 4, 34–37.Google Scholar
Lanolands, J. P. (1969). Studies on the nutritive value of the diet selected by grazing sheep. V. Further studies of the relationship between digestibility estimated in vitro from oesophageal fistula samples and from faecal and dietary composition. Anim. Prod. 11, 379–87.Google Scholar
Langlands, J. P., Corbett, J. L., McDonald, I. & Pullar, J. D. (1963 a). Estimates of the energy required for maintenance by adult sheep. I. Housed sheep. Anim. Prod. 5, 1–9.Google Scholar
Langlands, J. P., Corbett, J. L., McDonald, I. & Reid, G. W. (1963 b). Estimates of the energy required for maintenance by adult sheep. II. Grazing sheep. Anim. Prod. 5, 11–16.Google Scholar
Langlands, J. P. & Wheeler, J. L. (1968). The dyebanding and tattooed patch procedures for estimating wool production and obtaining samples for the measurement of fibre diameter. Aust. J. exp. Agric. Anim. Husb. 8, 265–9.CrossRefGoogle Scholar
Langlands, J. P. & Sutherland, H. A. M. (1969). An estimate of the nutrients utilized for live-weight gain by Merino Sheep. Br. J. Nutr. 23, 603–9.CrossRefGoogle ScholarPubMed
Langlands, J. P. & Bennett, I. L. (1973 a). Stocking intensity and pastoral production. I. Changes in the soil and vegetation of a sown pasture grazed by sheep at different stocking rates. J. agric. Sci., Camb. 81, 193–204.CrossRefGoogle Scholar
Langlands, J. P. & Bennett, I. L. (1973 b). Stocking intensity and pastoral production. II. Herbage intake of Merino sheep grazed at different stocking rates. J. agric. Sci., Camb. 81, 205–9.CrossRefGoogle Scholar
McManus, W. R., Arnold, G. W. & Paynter, J. R. (1964). Studies in the wool production of grazing sheep. 2. Variation in wool characteristics with season and stocking rate. Aust. J. exp. Agric. Anim. Husb. 4, 404–11.CrossRefGoogle Scholar
Mullaney, P. D., Brown, G. H., Young, S. S. Y. & Hyland, P. G. (1969). Genetic and phenotypic parameters for wool characteristics in fine-wool Merino, Corriedale and Polwarth sheep. I. Influence of various factors on production. Aust. J. agric. Res. 20, 1161–76.CrossRefGoogle Scholar
Sharkey, M. J., Davis, I. F. & Kenney, P. A. (1962). The effect of previous and current nutrition on wool production in southern Victoria. Aust. J. exp. Agric. Anim. Husb. 2, 160–9.CrossRefGoogle Scholar
Slee, J. & Carter, H. B. (1961). A comparative study of fleece growth in Tasmanian Fine Merino and Wiltshire Horn ewes. J. agric. Sci., Camb. 57, 11–19.CrossRefGoogle Scholar
Sumner, R. M. W. & Wickham, G. A. (1969). Some effects of an increased stocking level on wool growth. Proa. N.Z. Soc. Anim. Prod. 29, 208–17.Google Scholar
Williams, O. B. & Chapman, R. E. (1966). Additional information on the dye-banding technique of wool growth measurement. J. Aust. Inst. agric. Sci. 32, 298–300.Google Scholar
Young, B. A. & Corbett, J. L. (1972). Maintenance energy requirement of grazing sheep in relation to herbage availability. I. Calorimetric estimates. Aust. J. agric. Res. 23, 57–76.CrossRefGoogle Scholar