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Use of embryo transfer in genetic improvement of sheep

Published online by Cambridge University Press:  02 September 2010

C. Smith
C. Smith
Affiliation:
AFRC Animal Breeding Research Organisation, West Mains Road, Edinburgh EH9 3JQ
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Abstract

Embryo transfer following multiple ovulation could allow faster rates of genetic change in sheep, by increasing the effective female reproductive rate. The gains would come from lower generation intervals or increased selection among females, or both. They require good embryo transfer rates at 6 to 8 months of age. These are not adequate at present and need to be improved by research and development, justified by the extra genetic gains shown here to be possible. If high rates of embryo transfer (10 progeny per donor) could be achieved, then, with appropriate selection schemes, the rates of genetic change could be doubled compared with efficient schemes using normal reproduction. This applies to most traits, to those measured before reproductive age (growth traits and carcass traits estimated in the live animal), to female reproductive traits and to wool traits measured at 14 to 16 months of age. With moderate rates of embryo transfer (5 progeny per donor), gains of 50 to 70% in genetic response could be obtained. To limit the rate of inbreeding to moderate levels in a closed selection flock, some 100 to 200 females (1000 progeny) would be required. Application of the methods may be difficult with current breeding structures, and the development of special nucleus selection stocks i s proposed.

Type
Research Article
Information
Animal Production , Volume 42 , Issue 1 , February 1986 , pp. 81 - 88
Copyright
Copyright © British Society of Animal Science 1986

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References

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