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The effect of inbreeding on feed consumption and utilisation by sheep

Published online by Cambridge University Press:  02 September 2010

J. M. Doney
J. M. Doney
Affiliation:
Hill Farming Research Organisation, 29 Lauder Road, Edinburgh 9
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Extract

Twelve inbred (coefficient of inbreeding 25%) and 12 outbred, singlereared, Scottish Blackface castrated male lambs were taken at six months of age from amongst the progeny of three rams. They were housed and fed individually on a pelleted diet in three separate phases. In the first two phases restricted amounts were offered. These were calculated to produce, firstly, a small rate of live-weight gain and, secondly, a small rate of live-weight loss. In the third phase feed was offered to maximum voluntary intake during 2 two-hour periods daily.

On restricted intakes there were no significant differences between the groups. In the third phase the outbred sheep consumed 17% more feed than the inbred group and the daily rates of live-weight gain and wool growth were 33% and 27% higher, respectively. Since the inbred lambs were smaller, the voluntary intake per unit live-weight did not differ significantly between groups.

The estimated requirements of feed for maintenance (20·1 ± 0·4 and 21·9±0·6 g./kg. live-weight, respectively, for the outbred and inbred groups) differed significantly. There were no apparent differences in the estimated efficiency of conversion of available surplus feed to body tissue or wool growth.

Type
Research Article
Information
Animal Production , Volume 9 , Issue 3 , August 1967 , pp. 359 - 364
Copyright
Copyright © British Society of Animal Science 1967

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References

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