Hostname: page-component-848d4c4894-sjtt6 Total loading time: 0 Render date: 2024-07-01T13:05:03.003Z Has data issue: false hasContentIssue false

Lamb birthcoat relationship to the adult fleece in Merino, coarse wool Barki and Merino × Barki sheep crosses

Published online by Cambridge University Press:  27 March 2009

R. A. Guirgis
Affiliation:
Department of Animal Production, Desert Institute, Matareya, Cairo, Egypt

Summary

The present study was carried out on adult fleeces, of Merino, coarse wool Barki and five of their crosses, of known birthcoats. The adult fleece traits studied were clean fleece weight, mean fibre diameter and its variability and mean staple length and its variability.

Birthcoat-adult fleece relationship was dependent on the breed studied. In Barki, plateau array in the birthcoat developed to adult fleeces with higher values of mean fibre diameter and its variability, mean staple length and clean fleece weight than those with saddle array. In ⅝ Merino there was a gradient in staple length, running from plateau, via saddle, to ravine, with higher values of the coarser arrays. Differences occurred in variability of fibre diameter between plateau and saddle arrays in ⅜ and ⅝ Merino and between saddle and ravine in ½, ⅝ and ¾ Merino.

Differences occurred where birthcoats, with plateau array with precipice, in the curly-tip group, grew into adult fleeces with longer mean staple than those with transition in Barki sheep. In the other breed groups differences observed in saddle array, with different features, precipice or transition, at the birthcoat level, did not contribute differences in their adult fleeces.

Selection of Barki lambs with plateau fibre type array in their birthcoats would result in higher clean adult fleece weights that have coarser fibre diameter, with higher variability, and longer staple than those with saddle array. Within saddle array, selection of those with reduced SK% would develop into adult fleeces with higher clean fleece weight and those with reduced CT% would grow into adult fleeces with finer diameter.

Selection of lambs that have birthcoat ravine array in f, ⅜, ½, ⅝ and ¾ Merino would reduce the within-staple variability in their adult fleece fibre diameter.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1982

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Anderson, S. L. (1955). A relative humidity correction to the results of determination of the diameter of the wool fibres by the air flow method. Journal of the Textile Institute, Manchester 46, T 675.Google Scholar
Burns, M. (1955). Observations on Merino x Herdwick hybrid sheep with special reference to the fleece. Journal of Agricultural Science, Cambridge 46, 389406.CrossRefGoogle Scholar
Burns, M. (1972). Effect of ova transfer on the birthcoat of lambs. Journal of Agricultural Science, Cambridge 78, 16.CrossRefGoogle Scholar
Chapman, R. E. (1960). The biology of the fleece. Animal Research Laboratories Technical Paper, no. 3. Australia: Commonwealth Scientific and Industrial Research Organization.Google Scholar
Dry, F. W. (1965). Lamb fibre types. In Biology of Skin and Hair Growth (ed. Lyne, A. G. and Short, B. F.), pp. 127177. Sydney: Angus and Robertson.Google Scholar
Guirgis, R. A. (1973 a). Staple length and kemp as a basis of grading Barki wool. Alexandria Journal of Agricultural Research 21, 235240.Google Scholar
Guirgis, R. A. (1973 b). The study of variability in some wool traits in a coarse wool breed of sheep. Journal of Agricultural Science, Cambridge 80, 233238.CrossRefGoogle Scholar
Guirgis, R. A. (1977). Crossing Merino and a coarse wool breed of sheep; a study of the birthcoat of lambs. Journal of Agricultural Science, Cambridge 881, 375380.CrossRefGoogle Scholar
Guirgis, R. A. (1979). Birthcoat fibre type arrays of lambs and some adult fleece traits. Journal of Agricultural Science, Cambridge 93, 195201.CrossRefGoogle Scholar
Guirgis, R. A. (1980). Response to the use of Merino in improvement of coarse wool Barki sheep: an analysis of some cross-bred wool traits. Journal of Agricultural Science, Cambridge 95, 339347.CrossRefGoogle Scholar
International Wool Textile Organization- 19–71 (E) (1971). Method for the Determination of the I.W.T.O. Clean Wool Content in Greasy Wool. The International Wool Secretariat Research Department, Wool House, Carlton Gardens, London S.W.I.Google Scholar
Snedecor, G. W. & Cochran, W. G. (1970). Statistical Methods. Ames: Iowa State University Press.Google Scholar
Von Bergen, W. (1963). What the manufacturer requires in raw wool. Wool Technology and Sheep Breeding 10, 4349.Google Scholar