Hostname: page-component-5c6d5d7d68-wbk2r Total loading time: 0 Render date: 2024-08-21T19:18:52.087Z Has data issue: false hasContentIssue false

Seasonal and Other Changes in The gestation duration of Sheep

Published online by Cambridge University Press:  27 March 2009

D. Amir
Affiliation:
Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
A. Genizi
Affiliation:
Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
H. Schindler
Affiliation:
Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel

Summary

Data from 266 pregnancies of 144 Finn x German Mutton Merino and Finn x Awassi ewes were used to determine the effects of season of mating, dam and sire breeds, litter size and sex of the offspring, and age of the ewe on the duration of gestation.

June, September–October and January matings resulted in significantly different durations of gestation of 143·3, 145·3 and 146·1 days, respectively.

Suffolk rams’ matings resulted in a significantly shorter gestation than matings with German Mutton Merino, Schwarzkopf or cross-bred rams.

A highly significant linear regression (b = –0·80) of the duration of gestation on the number of lambs was found.

Male lambs were carried longer than female lambs.

The intraclass correlation between the gestation periods for lambs which were maternal half-sibs was highly significant.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1980

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

Alexander, G. (1956). Influence of nutrition upon duration of gestation in sheep. Nature, London 178, 10581059.CrossRefGoogle ScholarPubMed
Amir, D. & Schindler, H. (1977). Induction of oestrus and fertility of ewes at the beginning and the end of the sexual season. Hassadeh 57, 16631667 (Hebrew, with English summary).Google Scholar
Bosc, M. J. (1970). Etude de l'induction de la parturition chez les brebis par un corticostéroide de synthése, le fluoro–methyl prednisolone. Comptes Rendus de l'Académie des Sciences, Paris, Series D 270, 31273130.Google Scholar
Dickinson, A. G., Hancock, J. L., Hovell, J. R., Taylor, St C. S. & Wiener, G. (1962). The size of lambs at birth – a study involving egg transfer. Animal Production 4, 6479.Google Scholar
Forbes, J. M. (1967). Factors affecting the gestation length in sheep. Journal of Agricultural Science, Cambridge 68, 191194.CrossRefGoogle Scholar
Goot, H., Benjamin, R. W., Folman, Y. & Drori, D. (1974). [Crossbreeding Finn rams with German Mutton Merino ewes.] Hassadeh 54, 15311534 (Hebrew).Google Scholar
Goot, H., Folman, Y., Drori, D. & Eyal, E. (1975). [The Finn x Awassi cross of sheep (preliminary results).] Hassadeh 55, 18811883 (Hebrew).Google Scholar
Hoerl, A. E. & Kennard, R. W. (1970). Ridge regression: biased estimation for nonorthogonal problems. Technometrics 12, 6567.Google Scholar
Liggins, G. C., Grieves, S. A., Kendall, J. A. & Knox, B. S. (1972). The physiological roles of progesterone, oestradiol-17β and prostaglandin F2aa in the control of ovine parturition. Journal of Reproduction and Fertility, Supplement 16, 85103.Google Scholar
Lincoln, D. W. & Porter, D. C. (1979). Photoperiodic dissection of endocrine events at parturition. Animal Reproduction Science 2, 97115.CrossRefGoogle Scholar
Mitchell, J. A. & Yochim, J. M. (1970). Influence of environmental lighting on duration of pregnancy in the rat. Endocrinology 87, 472480.CrossRefGoogle ScholarPubMed
Terrill, C. & Hazel, L. N. (1947). Length of gestation in range sheep. American Journal of Veterinary Research 8, 6672.Google ScholarPubMed
Thimonier, J., Cognie, Y., Cornu, C., Schnebrger, J. & Vernusse, G. (1975). Intensive lamb production. Annales de Biologie Animate, Biochimie, Biophysique 15, 365367.CrossRefGoogle Scholar