Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-11-23T05:48:30.775Z Has data issue: false hasContentIssue false
  • English
  • Français

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
Get access

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

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Adalsteinsson, S. and Steingrímssonn, J. T. 1975. [Feeding experiments on sheep farms in Eastern Iceland.] Rádunautafundur Bunadarfélags Íslands og Rannsóknastofnunar landbúnadarins. (Mimeo graph)Google Scholar
Adalsteinsson, S. and Steíngrímssonn, J. T. 1976. [Feeding and productivity of sheep.] Rádunautafundur Rannsóknastofnunar landbúnadarinsog Búnadarfélag Íslands. (Mimeograph)Google Scholar
Ducker, M. J. and Boyd, J. S. 1977. The effect of body size and body condition on the ovulation rate of ewes. Anint. Prod. 24: 377–385.Google Scholar
Gunn, R. G., Doney, J. M. and Russel, A. J. F. 1969. Fertility in Scottish Blackface ewes as influenced by nutrition and body condition at mating. J. agric. Sci., Comb. 73: 289–294.CrossRefGoogle Scholar
Gunn, R. G., Doney, J. M. and Russel, A. J. F. 1972. Embryo mortality in Scottish Blackface ewes as influenced by body condition at mating and by post-mating nutrition. J. agric. Sci., Camb. 79: 19–25.CrossRefGoogle Scholar
Harvey, W. R. 1972. Instructions for use of LSMLMM (Least Squares and Maximum Likelihood General Purpose Program). Ohio State University. (Mimeograph)Google Scholar
Jonmundsson, J. V. 1977. A study of data from the sheep recording associations in Iceland. II. Ewe production traits. J. Agric. Res. Iceland 9: 31–42.Google Scholar
Morley, F. H. W., White, D. H., Kenney, P. A. and Davis, I. F. 1978. Predicting ovulation rate from liveweight in ewes. Agricultural Systems 3: 27–45.CrossRefGoogle Scholar
Glafsson, G. 1967. New methods for determination of digestibility. Handbdk baenda, 17: 188–291.Google Scholar
Palsson, H. and Thorsteinsson, S. S. 1969. Comparison of lamb production by heavy versus light ewes. J. Agric. Res. Iceland 1: 87–101.Google Scholar
Petursson, A. G. 1976. [On feeding and management of sheep.] Handbdk baenda 27: 173–179.Google Scholar
Rattray, P. V. 1977. Nutrition and reproductive efficiency. In Reproduction of Domestic Animals. 3rd ed. (ed. Cole, H. H. and Cupps, P. T.), pp. 553–575. Academic Press, New York.Google Scholar
Russel, A. J. F., Doney, J. M. and Gunn, R. G. 1969. Subjective assessment of body fat in live sheep. J. agric. Sci., Comb. 72: 451–454.CrossRefGoogle Scholar