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Causes of variation in dental characters of Scottish Blackface sheep in a hill flock, and relations to ewe performance

Published online by Cambridge University Press:  27 March 2009

A. F. Purser ,
G. Wiener  and
D. M. West
A. F. Purser
Affiliation:
ARC Animal Breeding Research Organisation, West Mains Road, Edinburgh, EH9 SJQ
G. Wiener
Affiliation:
ARC Animal Breeding Research Organisation, West Mains Road, Edinburgh, EH9 SJQ
D. M. West
Affiliation:
ARC Animal Breeding Research Organisation, West Mains Road, Edinburgh, EH9 SJQ
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Summary

Observations were made in three successive years on the dentition of Scottish Blackface ewes of 1½–4½ years old in a large hill flock in southern Scotland.

The number of permanent incisor teeth was not a reliable guide to age, since at each age there was variation about the modal number. The length of the central permanent incisors increased slightly with age, and associated with this there was a slight forward movement in the position at which these teeth occluded with the dental pad. The modal position was 1 mm behind the anterior point of the dental pad of gum. About 1·5 % of the observations had bite positions deviating by 5 mm or more from the mode.

Keeping the females during their first winter on low-ground pasture instead of the hill led to earlier eruption and slightly longer central incisors, but had little effect on bite position.

The heritability of the number of incisors present at any one age was estimated to be 0·39 ± 0·11 by paternal half-sib correlation and 0·80 ± 0·27 by daughter-dam regression. Estimates of h2 for incisor length were less than half these values and those for the measure of bite position were very small and not significantly different from zero.

For the ages up to 3½ years old, there were low but statistically significant correlations of number of incisors with ewe live weight (0·1–0·2) and fleece weight (around 0·1), incisor length with fleece weight (around 0·1) and at 1½ years old only between the bite measure and both weights (0·1). Weight of lamb weaned by the ewe was uncorrelated with these dental traits.

It is concluded that in this flock, culling on the dental characters studied would not have improved performance, and selection would not change the position of the bite.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 99 , Issue 2 , October 1982 , pp. 287 - 294
Copyright
Copyright © Cambridge University Press 1982

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References

Barnicoat, C. R. (1957). Wear in sheep's teeth. New Zealand Journal of Science and Technology 38, 583–632.Google Scholar
Beedie, G. (1980). Stanhope, ABRO's Scottish Hill Farm. Report 1980, ARC Animal Breeding Research Organisation, pp. 32–36. London: H.M.S.O.Google Scholar
Coop, I. E. & Clark, V. R. (1955). The influence of method of rearing as hoggets on the lifetime productivity of sheep. New Zealand Journal of Science and Technology A37, 214–228.Google Scholar
Donald, H. P. & Wiener, G. (1954). Observations of mandibular prognathism. The Veterinary Record 66, 479–481.Google Scholar
Franklin, M. C. (1950). The influence of diet on dental development in the sheep. Bulletin, Australian Council of Scientific and Industrial Research, Number 252.Google Scholar
Gunn, R. G. (1967). Levels of first winter feeding in relation to performance of Cheviot hill ewes. V. Dental development and persistence. Journal of Agricultural Science, Cambridge 69, 345–348.CrossRefGoogle Scholar
Hitchin, A. D. (1948). Relationships of occlusion and paradontal disease in sheep. The Dental Record 58, 251–254.Google Scholar
Mascall, L. (1662). The Gouernment of Cattel, p. 234. London: John Stafford & W. G.Google Scholar
Ministry Op Agriculture, Fisheries And Food (1977). Teeth loss in sheep. Agricultural Development and Advisory Service Ways and Means Panel Report.Google Scholar
Nordby, J. E., Terrill, C. E., Hazel, L. N. & Stoehr, J. A. (1945). The etiology and inheritance of inequalities in the jaws of sheep. The Anatomical Record 92, 235–254.Google Scholar
Purser, A. F. & Roberts, R. C. (1964). The effect of treatment during first winter on the subsequent performance of Scottish Blackface ewes. Animal Production 6, 273–284.Google Scholar
Purser, A. F. & Wiener, G. (1960). Variation in dental characteristics of Scottish Blackface sheep. Proceedings of the 32nd meeting of the British Society of Animal Production. Animal Production 2, 214 (Abstract).Google Scholar
Richardson, C., Richards, M., Terlecki, S. & Miller, W. M. (1979). Jaws of adult culled ewes. Journal of Agricultural Science, Cambridge 93, 521–529.Google Scholar
Starke, J. S. & Pretobius, A. G. (1955). Dentition of sheep as indication of age. Farming in South Africa 30, 53–58.Google Scholar
Sykes, A. R., Field, A. C. & Gunn, R. G. (1974). Effects of age and state of incisor dentition on body composition and lamb production of sheep grazing hill pastures. Journal of Agricultural Science, Cambridge 83, 135–142.Google Scholar
Wiener, G. & Donald, H. P. (1955). A study of variation in twin cattle. IV. Emergence of permanent incisor teeth. The Journal of Dairy Research 22, 127–137.CrossRefGoogle Scholar
Wiener, G. & Gardner, W. J. F. (1970). Dental occlusion in young bulls of different breeds. Animal Production 12, 7–12.Google Scholar
Wiener, G. & Purser, A. F. (1957). The influence of four levels of feeding on the position and eruption of incisor teeth in sheep. Journal of Agricultural Science, Cambridge 49, 51–55.Google Scholar
Youatt, W. (1856). Sheep, their Breeds, Management and Diseases. London: Baldwin.Google Scholar