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Selection on ram 18-month weight to improve lamb growth rate

Published online by Cambridge University Press:  02 September 2010

D. Croston ,
J. L. Read ,
D. W. Jones ,
D. E. Steane  and
C. Smith
D. Croston
Affiliation:
Meat and Livestock Commission, P.O. Box 44, Queensway House, Bletchley, Milton Keynes, MK2 2EF
J. L. Read
Affiliation:
Meat and Livestock Commission, P.O. Box 44, Queensway House, Bletchley, Milton Keynes, MK2 2EF
D. W. Jones
Affiliation:
Meat and Livestock Commission, P.O. Box 44, Queensway House, Bletchley, Milton Keynes, MK2 2EF
D. E. Steane
Affiliation:
Meat and Livestock Commission, P.O. Box 44, Queensway House, Bletchley, Milton Keynes, MK2 2EF
C. Smith
Affiliation:
Animal Breeding Research Organisation, Kings Buildings, West Mains Road, Edinburgh, EH9 3JQ
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Abstract

Thirteen pairs of Suffolk rams were selected on high and low 18-month adjusted live weight from six farms over 2 years, to establish the relationship between 18-month weight and early lamb growth. Progeny were first produced in recorded crossbred flocks (618 lambs) and then in an experimental flock of crossbred ewes (1083 lambs). Different results were obtained from the recorded and experimental flocks. The regressions of lamb 12- to 13-week weight on ram 18-month weight (within farm deviation) were 0·053 ± 0·022 kg and –0·004 ± 0·020 kg, respectively. These regressions for indirect selection correspond to ‘effective’ heritabilities for direct selection for lamb growth of 0·18 ± 0·07 and 0·02 ± 0·06 respectively. Improvement of early Iamb growth is discussed and it is concluded that selection for 18-month weight is unlikely to be a useful method.

Type
Research Article
Information
Animal Production , Volume 36 , Issue 2 , April 1983 , pp. 159 - 164
Copyright
Copyright © British Society of Animal Science 1983

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References

REFERENCES

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