Geographical isolation of native sheep breeds in the UK-Evidence of endemism as a risk factor to genetic resources

Amanda Carson, Matt Elliott, Julian Groom, Agnes Winter, Dianna Bowles

Research output: Contribution to journalArticlepeer-review


This study addresses the potential risk to the genetic resources of UK sheep breeds from endemism. Twelve native breeds are analysed that exist in significant numbers and continue to be commercially farmed livestock. The breeds were selected to represent regions of the British Isles: North of England hill breeds (Herdwick, Rough Fell, Lonk, Dalesbred), South of England breeds (Southdown, Romney, Devon Closewool, Exmoor Horn), Scottish breed (South Country Cheviot) and Welsh/Welsh border breeds (Welsh Hill Speckled Face, South Wales Mountain (Nelson), Clun Forest).

For each breed, numerical data were collected in collaboration with breed society members and analysed in terms of population size and structure together with the extent of their geographical range. The number of flocks per breed proved to be highly variable, questioning the assumption that has been made that the number of breeding units can be disregarded in the calculations of endangerment. The data also indicated that an average flock size for a breed cannot be estimated to gain an insight of the population structure, since this parameter was found to vary considerably within and between breeds. The endemism was best illustrated in the breed maps which clearly highlighted the degree to which each breed was associated with a distinct geographical area. From the maps, ten of the twelve breeds analysed were concentrated, but the flocks of two breeds were visually more dispersed. In numerical terms. the ten breeds were found to have up to 95% of their breed numbers concentrated within a radius of 65 km from the mean centre of each breed.

The study provides a valuable foundation for future research into genetic diversity within and between the sheep breeds analysed. a baseline of information to enable population trends to be examined and a robust evidence-base for policy decisions on Farm Animal Genetic Resources (FAnGR). (C) 2008 Elsevier B.V. All rights reserved.

Original languageEnglish
Pages (from-to)288-299
Number of pages12
JournalLivestock science
Issue number2-3
Publication statusPublished - Aug 2009


  • Sheep
  • Geographical isolation
  • Animal genetic resources
  • Biodiversity

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