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Post-natal development, dimensions of the skin follicle population and birthcoat follicular origin in Barki and ⅜ Merino lambs

Published online by Cambridge University Press:  27 March 2009

R. A. Guirgis
Affiliation:
Department of Animal Production, Desert Institute, Matareya, Cairo, Egypt
S. O. Amin
Affiliation:
Department of Animal Production, Desert Institute, Matareya, Cairo, Egypt
Y. S. Ghanem
Affiliation:
Department of Animal Production, Desert Institute, Matareya, Cairo, Egypt
N. A. EL-Sayed
Affiliation:
Department of Animal Production, Desert Institute, Matareya, Cairo, Egypt

Summary

In a study of two breed groups, coarse wool Barki and ⅜ Merino ⅜ Barki, data were obtained on skin histology from birth to the age of 1 year, birthcoat fibre type arrays and fibre-follicle relationship.

The ⅜ Merino exceeded Barki lambs in the maximum S/P ratio, values of which were 3·40 and 5·64 obtained at 6 and 8 months in Barki and ⅜ Merino respectively.

Internal diameters of primary follicles ranged from 39·0 to 64·7 and from 41·0 to 56·8 μm; those of secondaries ranged from 19·8 to 34·9 and from 22·6 to 33·3 μm in Barki and ⅜ Merino respectively.

The ratio of primary to secondary follicle diameters showed high values in both breed groups; averages were 1·89 and 1·71 for internal diameter and 1·86 and 1·71 for external diameter in Barki and ⅜ Merino respectively.

Birthcoat fibre type arrays were mostly saddle, only 8·3% were plateau (P3) in both breed groups.

In Barki primary centrals grew halo hairs, super sickle (A, A′, B), primary laterals produced super sickle (A, A′, B), sickles, coarse and medium curly tips, and secondaries mostly grew medium and fine curly tips and histerotrichs.

In ⅜ Merino primary centrals produced halo hairs, super sickle (A, A′, B), primary laterals grew super sickle (A, A′, B), sickles, medium curly tips, and secondaries produced medium and fine curly tips and histerotrichs.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1981

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References

REFERENCES

Burns, M. (1949). Studies on follicle population in relation to fleece changes in lambs of the English Leicester and Romney breeds. Journal of Agricultural Science, Cambridge 39, 6479.Google Scholar
Burns, M. (1953). Observation on the follicle population of Blackface sheep. Journal of Agricultural Science, Cambridge 43, 422431.CrossRefGoogle Scholar
Burns, M. (1954 a). Observation on the development of the fleece and follicle population of Suffolk sheep. Journal of Agricultural Science, Cambridge 44, 8699.CrossRefGoogle Scholar
Burns, M. (1954 b). The development of the fleece and follicle population in Herdwick sheep. Journal of Agricultural Science, Cambridge 44, 443464.CrossRefGoogle Scholar
Burns, M. (1955). Observations on Merino × Herdwick hybrid sheep with special reference to the fleece. Journal of Agricultural Science, Cambridge 46, 389406.Google Scholar
Burns, M. (1966). Merino birthcoat fibre types and their follioular origin. Journal of Agricultural Science, Cambridge 66, 155173.CrossRefGoogle Scholar
Burns, M. (1972). Effect of ova transfer on the birthcoat of lambs. Journal of Agricultural Science, Cambridge 78, 16.CrossRefGoogle 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
Daly, R. A. & Carter, H. B. (1955). The fleece growth of young Lincoln, Corriedale, Polwarth and fine-Morino maidon ewes under housed conditions and unrestricted and progressively restricted feeding ona standard diet. Australian Journal of Agricultural Research 6, 476513.CrossRefGoogle Scholar
Dry, F. W. (1933). Hairy fibres of the Romney sheep. New Zealand Journal of Agriculture 46, 1022.Google Scholar
Dry, F. W. (1934). Fibre type arrays and hairiness. New Zealand Journal of Agriculture 48, 3748.Google Scholar
Fahmy, M. H., Galal, E. S. E., Ghanem, Y. S. & Khishin, S. S. (1969). Crossbreeding of sheep under semi-arid conditions. Animal Production 11, 3560.Google Scholar
Fraser, A. S. (1952). Growth of wool fibres in sheep. Australian Journal of Agricultural Research 3, 419434.Google Scholar
Fraser, A. S. & Short, B. F. (1952). Competition between skin follicles in sheep. Australian Journal of Agricultural Research 3, 445452.Google Scholar
Guirgis, R. A. (1964). Fibre type arrays and kemp succession in sheep. M.Sc. thesis, University of Leeds.Google 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 88, 375380.CrossRefGoogle 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.Google Scholar
Rowell, J. G. & Walters, D. E. (1976). Analysing data with repeated observations in each experimental unit. Journal of Agricultural Science, Cambridge 87, 423432.CrossRefGoogle Scholar
Rudall, K. M. (1955). The size and shape of the papilla in wool follicles. Proceedings of the International Wool Textile Conference, Australia, F925.Google Scholar
Ryder, M. L. & Stephenson, S. K. (1968).Wool Growth. London: Aoademic Press.Google Scholar
Stephenson, S. K. (1956). Some aspects of gene dosage in N-type sheep. Australian Journal of Agricultural Research 7, 447468.Google Scholar
Tibbits, J. P. (1959). Post-natal growth changes in the cortex and medulla of the New Zealand Romney and N-type sheep. Journal of Agricultural Science, Cambridge 53, 358368.Google Scholar