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The seasonality of reproductive performance of Merino sheep in Britain

Published online by Cambridge University Press:  02 September 2010

W. M. Tempest  and
T. G. Boaz
W. M. Tempest
Affiliation:
Department of Animal Physiology and Nutrition, University of Leeds
T. G. Boaz
Affiliation:
Department of Animal Physiology and Nutrition, University of Leeds
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Summary

A study has been carried out to determine the length of the breeding season and the feasibility of lambing twice a year in Merino sheep in Britain.

Six groups of 18 ewes were exposed to rams at monthly intervals, and twice per year, from April 1969 to June 1970. A well-defined breeding season, from August to January, was found, and its shortness, linked with the inability of the ewes to conceive immediately post partum, prevented lambing twice in the year.

Type
Research Article
Information
Animal Production , Volume 17 , Issue 1 , August 1973 , pp. 33 - 41
Copyright
Copyright © British Society of Animal Science 1973

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References

REFERENCES

Averill, R. L. W. 1955. Fertility of the ewe. In Studies on Fertility (ed. Harrison, R. G.), Vol. 7, Ch. 14, pp. 139–148. Blackwell Scientific, Oxford.Google Scholar
Barrett, J. F., Reardon, T. F. and Lambourne, L. J. 1962. Seasonal variation in reproductive performance of Merino ewes in northern New South Wales. Aust. J. exp. Agric. Anim. Husb. 2: 69–74.CrossRefGoogle Scholar
Forbes, J. M. 1968. Partial synchronisation of oestrus in ewes resulting from the introduction of rams. Vie Int. Cong. Anim. Reprod. Artif. Insem., Paris, 1968, Vol. 11, pp. 1435–1438.Google Scholar
Hafez, E. S. E. 1952. Studies on the breeding season and reproduction of the ewe. J. agric. Sci., Comb. 42: 189–231.CrossRefGoogle Scholar
Hammond, J. 1957. Fertility and the production of fat lamb. Agric. Rev., Lond. 3: 23–27.Google Scholar
Hammond, J. 1960. In Farm Animals, Their Growth, Breeding and Inheritance, 3rd ed., p. 95. Edward Arnold, London.Google Scholar
Hunter, G. L. 1962. Observations on oestrus in Merinos. Proc. S. Afr. Soc. Anim. Prod. 1:67–69.Google Scholar
Hunter, G. L. 1968. Increasing the frequency of pregnancy in sheep. I. Some factors affecting rebreeding during the post-partum period. Anim. Breed. Abstr. 36: 347–378.Google Scholar
Kelley, R. B. 1937. Studies in fertility of sheep. Bull. Coun. sci. industr. Res. Aust., No. 112.Google Scholar
Kelley, R. B. 1946. Studies on the breeding performance of ewes. Bull. Coun. sci. industr. Res. Aust., No. 205.Google Scholar
Kelley, R. B. and Shaw, H. E. B. 1943. Fertility in sheep. An experimental study of periodicity of oestrus and non-breeding seasons in Australia. Bull. Coun. sci. industr. Res. Aust., No. 166.Google Scholar
Kirillov, V. 1944. [The organisation of two lamb crops in a year.] Sovhoz. Proizvod., 12: 34–36.Google Scholar
Large, R. V. 1970. The biological efficiency of meat production in sheep. Anim. Prod. 12: 393–401.Google Scholar
Newton, J. E. and Betts, J. E. 1966. Factors affecting litter size in the Scots Halfbred ewe. I. Treatment with PMS and progesterone. J. Reprod. Fert. 12: 165–175.CrossRefGoogle Scholar
Radford, H. M. and Watson, R. H. 1957. Influence of rams on ovarian activity and oestrus in Merino ewes in the spring and early summer. Aust. J. agric. Res. 8: 460–470.CrossRefGoogle Scholar
Riches, J. H. and Watson, R. H. 1954. The influence of the introduction of rams on the incidence of oestrus in Merino ewes. Aust. J. agric. Res. 5: 141–147.CrossRefGoogle Scholar
Schinckel, P. G. 1954. The effect of the presence of the ram on the ovarian activity of the ewe. Aust. J. agric. Res. 5: 465–469.CrossRefGoogle Scholar
Smith, I. D. 1962. Nutrition and oestrus. Aust. vet. J. 38: 338–340.CrossRefGoogle Scholar
Spedding, C. R. W. 1965. In Sheep Production and Grazing Management. 1st ed., p. 348. Bailliere, Tindall and Cox, London.Google Scholar
Spedding, C. R. W., Betts, J. E., Large, R. V., Wilson, I. A. N. and Penning, P. D. 1967. Productivity and intensive sheep stocking over afive-yearperiod. J. agric. Sci., Camb. 69: 47–69.CrossRefGoogle Scholar
Tempest, W. M. and Boaz, T. G. 1970. The impact of hormone treatment on the reproductive and lamb-rearing performance of Scottish Halfbred ewes. Anim. Prod. 12: 358 (Abstr.).Google Scholar
Underwood, E. J., Shier, F. L. and Davenport, N. 1944. Sheep husbandry in Western Australia. V. The breeding season of Merino, Crossbred and British breed ewes in the agricultural districts. J. Dept. Agric. West. Aust. 21: 135–143.Google Scholar
Watson, R. H. 1962. Seasonal variation in occurrence of oestrus in Merino ewes in Southern Victoria. Aust. vet. J. 38: 310–323.CrossRefGoogle Scholar