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Skin histology and birthcoat fibre-follicle relationships in Merino and ⅝ Merino lambs

Published online by Cambridge University Press:  27 March 2009

R. A. Guirgis
Affiliation:
Department of Animal Production, Desert Institute, Matareya, Cairo, Egypt
Y. S. Ghanem
Affiliation:
Department of Animal Production, Desert Institute, Matareya, Cairo, Egypt
S. O. Amin
Affiliation:
Department of Animal Production, Desert Institute, Matareya, Cairo, Egypt
M. M. El-Ganaieny
Affiliation:
Department of Animal Production, Desert Institute, Matareya, Cairo, Egypt

Summary

Skin biopsy samples from imported Merino and ⅝ Merino/⅜ Barki were examined from birth to the age of 1 year. Birthcoat fibre type arrays and fibre-follicle relationships were also studied.

Merino lambs had a greater S/P ratio than ⅝ Merino at all ages; values at 1 year of age were 9·98 and 6·87 respectively.

The ⅝ Merino lambs showed a wider range of follicle diameters than Merinos from birth to 1 year of age.

The ratio of primary to secondary follicle diameters showed higher values in ⅝ Merino than in Merinos. Merino gave lower values of follicle wall thickness than ⅝ Merino.

In Merino birthcoat samples, only one array was plain, representing 4%, whereas the rest were saddle. In ⅝ Merino the majority of fibre type arrays were plain, representing 75 %, whereas the rest were saddle and plateau.

In Merino, because of the absence of halo hairs and super sickles, only two samples had few super sickle B; primary central follicles were occupied by sickle fibres, medium with large sickle ends as well as curly tips, and primary lateral follicles had mostly medium and fine curly tips, only four samples had sickle fibres, and secondary follicles produced medium and fine curly tips and histerotrichs.

In ⅝ Merino primary central follicles produced halo hairs, super sickle A, A', B and occasionally sickle fibres, primary lateral follicles grew super sickle A, A', B, sickle fibres and curly tip fibres, and secondary follicles had medium and fine curly tips and histerotrichs.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1981

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References

REFERENCES

Burns, M. (1955). Observations on Merino × Herdwick hybrid sheep with special reference to the fleece. Journal of Agricultural Science, Cambridge 46, 389406.CrossRefGoogle Scholar
Burns, M. (1966). Merino birthcoat fibre types and their follicular origin. Journal of Agricultural Science, Cambridge 66, 155173.CrossRefGoogle Scholar
Burns, M. (1967). The Katsina wool project. II. Coat and skin data from ¾ Merino and Wensleydale crosses. Tropical Agriculture, Trinidad 44, 253274.Google Scholar
Burns, M. (1972). Effect of ova transfer on the birthcoat of lambs. Journal of Agricultural Science, Cambridge 78, 16.CrossRefGoogle Scholar
Carter, H. B. & Hardy, M. H. (1947). Studies in the biology of the skin and fleece of sheep. Australian Council of Scientific and Industrial Research, Bulletin no. 215.Google Scholar
Clarke, W. H. (1960). A histological technique for the study of the skin follicle population in sheep. In Biology of the Fleece (ed. Fraser, A. S. and Short, B. F.), pp. 9297. Animal Research Laboratories Technical Paper no. 3, C.S.I.R.O.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. 89104. Sydney: Angus and Robertson.Google Scholar
El-Sayed, N. A. (1979). A study of the physiology of wool follicles in crosses between Barki and Merino sheep. M.Sc. thesis, Ain Shams University, Egypt.Google Scholar
Fraser, A. S. (1952). Growth of wool fibres in sheep. Australian Journal of Agricultural Research 3, 419434.CrossRefGoogle Scholar
Fraser, A. S. & Hamada, M.s K. O. (1952). Observations on the birthcoats and skins of several breeds and crosses of British sheep. Proceedings of the Royal Society of Edinburgh B 64, 462477.Google Scholar
Fraser, A. S., Boss, J. M. & Wright, G. M. (1954). Development of the fibre population in N·type sheep. Australian Journal of Agricultural Research 5, 490502.CrossRefGoogle Scholar
Fraser, A. S. & Short, B. F. (1952). Competition between skin follicles in sheep. Australian Journal of Agricultural Research 3, 445452.CrossRefGoogle Scholar
Fraser, A. S. & Short, B. F. (1960). The biology of the fleece. Animal Research Laboratories Technical Paper no. 3. Commonwealth Scientific and Industrial Research Organization, Australia.Google Scholar
Hardy, M. H. & Lyne, A. G. (1956 a). The pre-natal development of wool follicles in Merino sheep. Australian Journal of Biological Science 9, 423441.CrossRefGoogle Scholar
Hardy, M. H. & Lyne, A. G. (1956 b). Proposed terminology of wool follicles in sheep. Nature, London 177, 705706.CrossRefGoogle Scholar
Marai, I. F. M. (1963). Wool follicles, types and density. Wool follicle development in some crossbred sheep. Ph.D. thesis, University of Cairo, Egypt.Google Scholar
Marai, I. F. M. & Shafei, M. M. (1964). The post-natal check in the development of the wool follicles. Journal of Animal Production, United Arab Republic 4, 145150.Google Scholar
Priestley, G. C. (1967). Seasonal changes in the inner root sheath of the primary follicles of Herdwick sheep. Journal of Agricultural Science, Cambridge 69, 912.CrossRefGoogle Scholar
Ragab, M. T. & Marai, I. F. M. (1969). Some wool follicle characteristics in crossbreds between Egyptian coarse wool sheep and long and fine wool breeds. Journal of Agricultural Science, Cambridge 73, 211213.CrossRefGoogle Scholar
Ross, J. M. (1954). Development of the follicle population in N·type sheep. Australian Journal of Agricultural Research 5, 484489.CrossRefGoogle Scholar
Rowell, J. G. & Walters, D. E. (1976). Analysing data with repeated observations on each experimental unit. Journal of Agricultural Science, Cambridge, 87, 423432.CrossRefGoogle Scholar
Ryder, M. L. & Stephenson, S. K. (1968). Wool Growth. London: Academic Press.Google Scholar