Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-27T10:34:53.743Z Has data issue: false hasContentIssue false
  • English
  • Français

The post-natal development of the follicle population in English Romney Lambs

Published online by Cambridge University Press:  27 March 2009

A. B. Wildman
A. B. Wildman
Affiliation:
Wool Industries Research Association, Leeds
Get access Rights & Permissions [Opens in a new window]

Extract

The follicle ratio S/P and the fibre ratio Sf/Pf have been determined for various post-natal ages of English Romney lambs in six lamb crops.

A maximum site-sampling error has been determined for use in assessing the degree of significance of differences in values of the ratio S/P determined from successive skin samples from individual lambs. Variations encountered in these Romney lambs in the level of their follicle and fibre ratios, in their rates of change and in the degree of their association with live-weight changes show that rigid conclusions based on data from one lamb crop only are not justified. An intensive study of birth and 8-day old samples has shown that follicles may regress in the early post-natal life of the lamb.

Not all follicle anlagen are initiated before birth and the ‘ceiling value’ of the adult ratio Sf/Pf is not necessarily determined or set pre-natally except in the sense of there being a genetic maximum which may or may not be attained. Low restricted follicle and fibre ratios at birth may increase rapidly postnatally and high ratios at birth may increase little, if at all, post-natally. The follicle and fibre ratio may increase even between the ages of 6 and 12 months.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 65 , Issue 3 , December 1965 , pp. 301 - 313
Copyright
Copyright © Cambridge University Press 1965

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

Burns, M. (1949). J. Agric. Sci. 39, 64.CrossRefGoogle Scholar
Burns, M. (1953). J. Agric. Sci. 43, 422.CrossRefGoogle Scholar
Burns, M. (1954a). J. Agric. Sci. 44, 86.CrossRefGoogle Scholar
Burns, M. (1954b). J. Agric. Sci. 44, 443.CrossRefGoogle Scholar
Burns, M. (1955). J. Agric. Sci. 46, 389.CrossRefGoogle Scholar
Carter, H. B. (1943). Bull. Counc. Sci. Industr. Res. Aust., no. 164.Google Scholar
Carter, H. B. (1955). An. Breed. Abstr. 23, 101.Google Scholar
Carter, H. B. & Clarke, W. H. (1957). Aust. J. Agric. Res. 8, 91.CrossRefGoogle Scholar
Carter, H. B. & Tibbits, J. P. (1959). J. Agric. Sci. 52, 106.CrossRefGoogle Scholar
Doney, J. M. & Smith, W. F. (1964). Anim. Prod. 6, 155.Google Scholar
Ferguson, K. A., Schinckel, P. G., Carter, H. B. & Clarke, W. H. (1956). Aust. J. Biol. Sci. 9, 575.CrossRefGoogle Scholar
Hammond, J. (1940). Farm Animals. London: Arnold.Google Scholar
Hardy, M. H. & Lyne, A. G. (1956). Nature, Lond., 177, 705CrossRefGoogle Scholar
Lyke, A. G. (1961). Aust. J. Biol. Sci. 14, 141Google Scholar
Ryder, M. L. (1955). J. Text. hist. 46, T565.Google Scholar
Ryder, M. L. (1957). J. Agric. Sci. 49, 275.CrossRefGoogle Scholar
Schtnckel, P. G. (1953). Nature, Lond., 171, 310.CrossRefGoogle Scholar
Schinckel, P. G. (1955a). Aust. J. Agric. Res. 6, 68.CrossRefGoogle Scholar
Schinckel, P. G. (1955b), Aust. J. Agric. Res. 6, 308.CrossRefGoogle Scholar
Schinckel, P. G. & Short, B. F. (1961). Aust. J. Agric. Res. 12, 176.CrossRefGoogle Scholar
Short, B. F. (1955a). Aust. J. Agric. Res. 6, 62.CrossRefGoogle Scholar
Short, B. F. (1955b). Aust. J. Agric. Res. 6, 863.CrossRefGoogle Scholar
Wildman, A. B. (1958). J. Agric. Sci. 51, 307.CrossRefGoogle Scholar