Hostname: page-component-cd9895bd7-dk4vv Total loading time: 0 Render date: 2024-12-25T06:44:40.479Z Has data issue: false hasContentIssue false

The study of kemp succession in the adult fleece of two coarse-wool breeds of sheep in relation to the birthcoat

Published online by Cambridge University Press:  27 March 2009

R. A. Guirgis
Affiliation:
Department of Animal Production, College of Agriculture and Forestry, Mosul University, Iraq
N. T. Kazzal
Affiliation:
Department of Animal Production, College of Agriculture and Forestry, Mosul University, Iraq
A. M. Zaghloul
Affiliation:
Department of Animal Production, College of Agriculture and Forestry, Mosul University, Iraq

Summary

A study of the birthcoat and its relation to kemp succession in the adult fleece of coarse-wool Awassi and Hamdani sheep was carried out, as an aid to early selection. Lambs were covered, at the age of 2 months up to 15 months, by fixing patches of canvas on six body positions.

Both Awassi and Hamdani birthcoats had high halo hair grades. The animals played the dominant role in affecting different traits of the birthcoat which indicated the importance of genetic factors in further development of the birthcoat. The birthcoat of both types of lambs showed only coarse (plateau) and less coarse (saddle) fibre type arrays.

Hamdani had more kemp as Gt and G2 (first and second generations respectively) than Awassi sheep. The shed Gx following the different fibre type arrays, showed some overlapping between plateau and saddle. The same arrays of the birthcoat behaved differently on the different positions, where generally the anterior positions had less kemp than those posteriorly. Percentages of shed fibres were 100, 17·14, 2·38 and 0·35 of halo hairs, super sickles, sickles and chalky curly tips respectively in Awassi. Corresponding figures were 100, 29·26, 5·87 and 7·73 in Hamdani. In Awassi, halo hairs, of the birthcoat, showed a relatively high correlation (P < 0·01) with G1 kemp on the hip and britch. Within saddle array, in Awassi, the correlation between halo hairs and Gx kemp showed the highest values (P < 0·01), whereas in Hamdani the correlation between super sickles in the birthcoat and G2 kemp showed medium values (P < 0·05).

Selection of high halo hair grade lambs, in the birthcoat, that have saddle arrays, with high percentage of sickle fibres in Awassi and with low percentage of super sickles in Hamdani, would result in low percentages of kemp in the adult fleece. High halo hair grades would be necessary for early survival of lambs.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1979

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

Burns, M. (1953). Observations on the follicular population of Blackface sheep. Journal of Agricultural Science, Cambridge 43, 423431.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.Google Scholar
Burns, M. (1966). Merino birthcoat fibre types and their follicular origin. Journal of Agricultural Science, Cambridge 66, 155173.Google Scholar
Burns, M. (1967). The Katsina wool project. II. The coat and skin data from J 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.Google Scholar
Carter, H. B. (1939). Fleece density and the histology of the Merino skin. Australian Veterinary Journal 15, 210213.Google Scholar
Carter, H. B. (1943). Studies in the biology of the skin and fleece of sheep. 1. The development and general histology of the follicle group in the skin of the Merino. C.S.I.R.O. Australia Bulletin, No. 164.Google Scholar
Deshpande, A. K. (1948). Studies on the biology of the fleeco of the Scots Mountain Blackface lamb. Ph.D. thesis, University of Leeds.Google Scholar
Dry, F. W. (1965). Lamb fibre types. In Biology of the Skin and Hair Growth(ed. Lyne, A. G. and Short, B. F.), pp. 89104. Sydney: Angus and Robertson.Google Scholar
Dry, F. W. (1975). The Architecture of Lambs' Coats; a Speculative Study. Palmerston North, New Zealand: Massey University.Google Scholar
Dry, F. W. & Stephenson, S. K. (1954). Presence and absence of the pre-natal check in lambs' birthcoats. Nature, London 173, 878879.Google Scholar
Fraser, A. S., Ross, J. M. & Wright, G. M. (1954). Development of the fibre population in N-type sheep. Australian Journal of Agricultural Research 5, 490502.Google Scholar
Goot, H. (1941). Evolution of the fleece of the sheep. Nature, London 148, 596597.CrossRefGoogle Scholar
Guirgis, R. A. (1967). Fibre type arrays and kemp succession in sheep. Journal of Agricultural Science, Cambridge 68, 7585.Google Scholar
Guibgis, 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
Lyne, A. G. (1961). The postnatal development of wool follicles, shedding, and skin thickness in inbred Merino and Southdown-Merino crossbred sheep. Australian Journal of Biological Sciences 14, 141156.CrossRefGoogle Scholar
Pubser, A. F. & Karam, H. A. (1967). Lamb survival, growth and fleece production in relation to birthooat type among Welsh Mountain sheep. Animal Production 9, 7585.Google Scholar
Ross, J. M. (1954). Development of the follicle population in N-type sheep. Australian Journal of Agricultural Research 5, 484489.Google Scholar
Ross, J. M. & Wright, G. M. (1954). Kemp succession in N-type sheep. Australian Journal of Agricultural Research 5, 503510.Google Scholar
Ryder, M. L. & Priestley, G. C. (1977). The use of skin autografts to study wool growth cycles in sheep. Research in Veterinary Science 2 310318.CrossRefGoogle Scholar
Slee, J. & Caster, H. B. (1962). Fibre shedding and fibre-follicle relationships in the fleeces of Wiltshire horn x Scottish Blackface sheep crosses. Journal of Agricultural Science, Cambridge 58, 309326.CrossRefGoogle Scholar
Snbdecor, G. W. & Cochran, W. G. (1970). Statistical Methods, 5th ed.Ames, Iowa: Iowa State University Press.Google Scholar
Stephenson, S. K. (1956). Some aspects of gene dosage in N-type sheep. Australian Journal of Agricultural Research 7, 447468.CrossRefGoogle Scholar