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The independent effects of live weight and body condition on fecundity and productivity of Icelandic ewes

Published online by Cambridge University Press:  02 September 2010

S. Adalsteinsson
S. Adalsteinsson
Affiliation:
The Agricultural Research Institute, Keldnaholt vjVesturlandsveg, 110 Reykjavik, Iceland
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Abstract

In an experiment carried out on five farms in 3 years and comprising 1221 annual weight records of adult ewes, an increased level of feedingwas comparedwith feeding according to farming practice. The higher feeding level started 6 weeks before mating andfinishedjust before lambing. Significant effects of feeding level on ewe live weight and body condition, ewe fecundity and the birth and weaning weights of lambs were found.

Ewe fecundity increasedlinearly with ewelive weight at 8 weeks prior t o mating (b=1·05 lambs/kg per 100 ewes), curvilinearly with ewe body condition score at 8 weeks before mating (maximum at score 3·32) and curvilinearly with weight gain from 8 to 2 weeks before mating (maximum at 2·3 kg gain). A 10% range in live weight, condition score and live-weight gain resulted in a predicted fecundity range of 21 lambs per 100 ewes alive at lambing. Changes in weight and condition score during the mating period did not affect ewe fecundity.

Type
Research Article
Information
Animal Production , Volume 28 , Issue 1 , February 1979 , pp. 13 - 23
Copyright
Copyright © British Society of Animal Science 1979

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References

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