Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-22T16:46:21.241Z Has data issue: false hasContentIssue false

Fertility in southdown sheep1

Published online by Cambridge University Press:  27 March 2009

J. E. Nichols
Affiliation:
(Animal Breeding Research Department, University of Edinburgh.)

Extract

Data from 26 flocks, involving a total of 5014 pure-bred Southdown ewes, were available for analysis and discussion. For ewes of all ages the proportion giving birth to twins is closely associated with the total yield of lambs, and while barrenness and abortion may to a certain extent be due to the same causes, it is those factors which cause abortion which also affect the yield by reducing the number of single births, rather than the number of multiple births.

The low fertility of shearling ewes is due to barrenness through reduced or delayed ovulation.

The writer wishes to express his thanks to the breeders who supplied the records of their flocks and particularly to the Honorary Secretary of the Southdown Sheep Society for his help in the collection of these records.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1926

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

Bell, A. G. (1912). Sheep Breeding Experiments on Beinn Bhreagh. Sci. N.S. 36, 378384.CrossRefGoogle ScholarPubMed
Carlyle, W. L. and McConnell, T. F. (1902). Some Observations on Sheep Breeding from the Experiment Station Flock Records. Univ. Wis. Agr. Exp. Sta. Bull. 95, 119.Google Scholar
Castle, W. E. (1924). Genetics of the Multi-nippled Sheep. Journ. Hered. 15, 7585.Google Scholar
Corner, G. W. (1923). The Problem of Embryonic Pathology of Mammals, with Observations on Intra-uterine Mortality in the Pig. Amer. Journ. Anat. 31, 523545.Google Scholar
Ewart, J. C. (1897). A Critical Period in the Development of the Horse. Black, 1897.Google Scholar
Hammond, J. (1914). On Some Factors Controlling Fertility in Domestic Animals. Journ. Agr. Sci. 5, 263277.CrossRefGoogle Scholar
Hammond, J. (1921). Further Observations on the Factors controlling Fertility and Foetal Atrophy. Journ. Agr. Sci. 11, 337366.CrossRefGoogle Scholar
Heape, W. (1899). Note on the Fertility of Different Breeds of Sheep, with Remarks on the Prevalence of Abortion and Barrenness therein. Proc. Roy. Soc. 65, 99111.Google Scholar
Heape, W. (1899). Abortion, Barrenness, and Fertility in Sheep. Journ. Boy. Agr. Soc. 10, 217248.Google Scholar
Humphrey, G. C. and Kleinheinz, F. (1907). Observations on Sheep Breeding from Records of the University Flock. 24th Ann. Rpt. Wisc. Agr. Exp. Sta. 2540.Google Scholar
Jones, S. V. H. and Rouse, J. E. (1920). The Relation of Age of Dam to Observed Fecundity in Domesticated Animals. I. Multiple Births in Cattle and Sheep. Journ. Dairy Sci. 3, 260290.CrossRefGoogle Scholar
Marshall, F. H. A. (1904). Fertility in Sheep. Trans. Highl. Agr. Soc. 3443.Google Scholar
Marshall, F. H. A. (1905). Fertility in Scottish Sheep. Proc. Roy. Soc. B. 77, 5862.Google Scholar
Marshall, F. H. A. (1908). Fertility in Scottish Sheep. Trans. Highl. Agr. Soc. 131151.Google Scholar
Marshall, F. H. A. (1908). The Effects of Environment and Nutrition upon Fertility. Sci. Prog. 7, 19.Google Scholar
Nichols, J. E. (1924). Fertility in Sheep. Journ. Minist. Agr. 31, 835843.Google Scholar
Popenoe, P. (1914). Sex Determination in Sheep. (Compiled by the Editor from the records of Alexander Graham Bell.) Journ. Hered. 5, 4757.Google Scholar