Hostname: page-component-78c5997874-j824f Total loading time: 0 Render date: 2024-11-19T11:46:33.679Z Has data issue: false hasContentIssue false

Genetic conservation of rare British sheep: the Portland, Manx Loghtan and Hebridean breeds

Published online by Cambridge University Press:  27 March 2009

S. J. G. Hall
Affiliation:
Research Group in Mammalian Ecology and Reproduction, Physiological Laboratory, Downing Street, Cambridge, GB2 3EO

Summary

Pedigree analyses were conducted of the Portland, Manx Loghtan and Hebridean sheep. These breeds are kept in small flocks, usually with only one ram active. Total population, and number of flocks have grown since registration started in 1975. Gene flow among flocks arisesfrom transfers of rams and of ewes: about 70% of breeding rams and 40% of breeding ewes have been transferred. Between half and three-quarters of the 1984 lamb crop were measurably inbred. More ram lambs are registered than would be expected in commercial practice.

About a third of flocks supplied rams to other flocks showing that these breeds do not have a very hierarchical structure. There is, however, a tendency towards hierarchical structure in the Manx Loghtan. A high proportion of the animals registered as foundation stocks in the earlyyears of the Combined Flock Book were represented in the pedigrees of recent lamb crops, i.e. genetic conservation has, on the whole, been achieved.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1986

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

Alderson, G. L. H. (1975). The Rare Breeds Survival Trust livestock survey, 1974. Ark 2, 109112.Google Scholar
Alderson, G. L. H. (1983). Current status of primitive and rare breeds. In Guide to the Primitive Breeds of Sheep and their Crosses (Elwes, H. J., 1913): reprinted with additional text by the Rare Breeds Survival Trust, pp. xiiixxiv.Google Scholar
Alderson, G. L. H. (1985). The conservation of animal genetic resources in Great Britain. Animal Genetic Resources Information (FAO/UNEP) 4, 2631.CrossRefGoogle Scholar
Anon. (1976). Portland sheep. Ark 3, 78.Google Scholar
Anon.(1981). Portland breed structure analysis. Ark 8, 301.Google Scholar
Anon. (1983). How concern for genetic conservation created the Rare Breeds Survival Trust. Ark 10, 156158.Google Scholar
Anon. (1985). Combined flock book. Ark 11, 810.Google Scholar
Baker, C. M. A. & Manwell, C. (1985). Biochemical markers and the genetic structure of the Jersey breed of cattle. Animal Blood Groups and Biochemical Genetics 16, suppl. 1, 5758.Google Scholar
Bowman, J. C. & Aindow, C. T. (1974). Genetic conservation and the less common breeds of British cattle, pigs and sheep. University of Reading Department of Agriculture and Horticulture Study no. 13.Google Scholar
Carter, R. C. (1940). A genetic history of Hampshire sheep. Journal of Heredity 31, 8993.CrossRefGoogle Scholar
Dickinson, W. F. & Lush, J. L. (1933). Inbreeding and the genetic history of the. Rambouillot sheep in America. Journal of Heredity 24, 1933.CrossRefGoogle Scholar
Dymond, A. J. (1979). Minority breeds at the N.A.C. Ark 6, 277279.Google Scholar
Elwes, H. J. (1913). Guide to the Primitive Breeds of Sheep and their Grosses. Reprinted with additional text in 1983; National Agricultural Centre, Warwickshire. Rare Breeds Survival Trust.Google Scholar
Falco, M. J. (1975). The calculation of inbreeding coefficients. Biometrics 31, 993.CrossRefGoogle Scholar
Fogarty, N. M. (1978). Pedigree Dorset Horn sheep in Australia. 2. Breed structure and genetic analysis. Australian Journal of Experimental Agriculture and Animal Husbandry 18, 173182.CrossRefGoogle Scholar
Henson, E. (1981a). A study of the congenital defect ‘split eyelid’ in the multihorned breeds of British sheep. Ark 8, 8490.Google Scholar
Henson, E. (1981b). Manx Loghtans on the Isle of Man. Ark 8, 125128.Google Scholar
Lambertson, W. R. & Thomas, D. L. (1984). Effects of inbreeding in sheep: a review. Animal Breeding Abstracts 52, 287297.Google Scholar
Lush, J. L. (1943). Animal Breeding Plans, 2nd edn.Ames, Iowa: Iowa State College Press.Google Scholar
Martin, I. (1976a). A genetic analysis of the Galway sheep breed. 1. Some aspects of population dynamics of the pedigree and non-pedigree Galway sheep breed. Irish Journal of Agricultural Research 14, 245253.Google Scholar
Martin, I. (1975b). A genetic analysis of the Galway sheep breed. 2. The breed structure of the pedigree and non-pedigree Galway sheep breed. Irish Journal of Agricultural Research 14, 255267.Google Scholar
Martin, I. (1978). The Galway sheep. Ark 5, 8687.Google Scholar
Rare Breeds Survival Trust (1985). Rare Breeds Facts, 1985 Edition. National Agricultural Centre, Warwickshire: Rare Breeds Survival Trust.Google Scholar
Rochambeau, H. De & Chevalet, C. (1982). Some aspects of the genetic management of small breeds. Proceedings of the 2nd World Congress of Genetics applied to Livestock Production, Madrid VII, pp. 282287.Google Scholar
Sieqel, S. (1956). Nonparametric Statistics for the Behavioral Sciences. Tokyo: McGraw-Hill Kogakusha.Google Scholar
Smith, C. (1984). Economic benefits of conserving animal genetic resources. Animal Genetic Resources Information (FAO/TJNEP) 3, 1014.CrossRefGoogle Scholar
Sokal, R. R. & Rohlf, F. J. (1981). Biometry, 2nd edn.San Francisco: W. H. Freeman.Google Scholar
Wiener, G. (1953). Breed structure in the pedigree Ayrshire cattle population in Great Britain. Journal of Agricultural Science, Cambridge 43, 123130.CrossRefGoogle Scholar
Wiener, G. (1961). Population dynamics in fourteen lowland breeds of sheep in Great Britain. Journal of Agricultural Science, Cambridge 57, 2128.CrossRefGoogle Scholar