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Season of birth and the response to hemicastration in lambs

Published online by Cambridge University Press:  02 September 2010

R. B. Land ,
D. J. Drury  and
Marjorie Fordyce
R. B. Land
Affiliation:
ARC Animal Breeding Research Organisation, West Mains Road, Edinburgh EH9 3JQ
D. J. Drury
Affiliation:
ARC Animal Breeding Research Organisation, West Mains Road, Edinburgh EH9 3JQ
Marjorie Fordyce
Affiliation:
ARC Animal Breeding Research Organisation, West Mains Road, Edinburgh EH9 3JQ
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Abstract

Testis diameter and body weight were recorded for 37 Finn-Dorset ram lambs born in winter and 38 born in summer 1977 from 8 to 24 weeks of age. Testis growth in summer-born ram lambs reared during a period of decreasing daylength was more rapid than that of winter-born lambs reared during a period of increasing daylength. Hemicastration at 12 weeks of age (19 of the winter-born and 18 of the summer-born lambs) increased the rate of growth of the remaining testis. Season of birth did not affect the response to hemicastration. It was deduced that the feed-back of gonadal hormones on gonadotrophin release was similar in both seasons.

Type
Research Article
Information
Animal Production , Volume 29 , Issue 3 , December 1979 , pp. 379 - 384
Copyright
Copyright © British Society of Animal Science 1979

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References

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