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The incidence of swayback among lambs with particular reference to genetic factors

Published online by Cambridge University Press:  27 March 2009

Gerald Wiener  and
M. R. Sampford
Gerald Wiener
Affiliation:
Animal Breeding Research Organization, West Mains Road, Edinburgh, 9
M. R. Sampford
Affiliation:
A.R.C. Unit of Statistics, Buccleuch Place, Edinburgh, 8
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Summary

The incidence of swayback among lambs in two flocks, previously reported, was reanalysed by a specially developed modification of the probit analysis technique in order to allow for the joint complications of an all-or-none trait and a large number of possible classifications for the animals in each flock. The form of analysis described yields predictions of the probability of swayback among lambs for the given circumstances.

Breed and sire within breed each affected the probability appreciably even when allowance for live weight of ewe and lamb was made. The effects of live weight, though significant in each flock, were not consistent in direction between the flocks. Other significant factors affecting swayback incidence were the manner of rearing the lambs, week of birth, and, in one flock, the sex of the lamb.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 73 , Issue 1 , August 1969 , pp. 25 - 31
Copyright
Copyright © Cambridge University Press 1969

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References

REFERENCES

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