Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-20T04:44:24.614Z Has data issue: false hasContentIssue false

A note on ovulation rate and embryonic survival in D'man ewes

Published online by Cambridge University Press:  02 September 2010

A. Lahlou-Kassi
Affiliation:
Department of Reproduction and Artificial Insemination, Hassan II Agronomic and Veterinary Institute, Rabat, Morocco
M. Marie
Affiliation:
Department of Reproduction and Artificial Insemination, Hassan II Agronomic and Veterinary Institute, Rabat, Morocco
Get access

Abstract

The elements of prolificacy have been analysed for the D'man sheep, a prolific Moroccan breed, by laparotomy on 38 animals. The average ovulation rate was 2·50 (s.e.0·45); a slight difference was observed between nulliparous and multiparous ewes due to high simultaneous activity by both ovaries in the latter group. Embryonic survival (42% overall) was 94% (87 to 100%) for multiparous and 44% (36 to 52%) for the nulliparous ewes at one ovulation, decreasing with increasing numbers of corpora lutea. The average litter size showed an optimum at four ovulations.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1981

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

Barki, L. 1974. Contribution à l'etude de la race D'man. Analyse des structures ovines dans les zones de Goulmima et Jorf. Mèm. de fin d'étude E.N.A. Meknes.Google Scholar
Bouix, J. 1975. Un des elements majeurs de la mise en valeur des palmeraies: la race ovine D'man. Options Méditerr. 26: 8793.Google Scholar
Bouix, J., Kadiri, M. and Chari, A. 1974. Performances enregistrées dans les troupeaux pépinières de la race ovine D'man. Awamia, Rabat 52: 6797.Google Scholar
Bouix, J., Kadiri, M., Chari, A., Ghanime, R. and Rami, A. 1977. Fiche signaletique de la race D'man. Hommes, Terre Eaux, Rabat 6: 911.Google Scholar
Bradford, G. E., Quirke, J. F. and Hart, R. 1971. Natural and induced ovulation rate of Finnish Landrace and other breeds of sheep. Anim. Prod. 13: 627635.Google Scholar
Griffiths, J. G., Gunn, R. G. and Doney, J. M. 1970. Fertility in Scottish Blackface ewes as influenced by climatic stress. J. agric. Sci., Camb. 75: 485488.CrossRefGoogle Scholar
Hanrahan, J. P. and Quirke, J. F. 1975. Repeatabilit y of the duration of oestrus and breed differences in the relationship between duration of oestrus and ovulation rate of sheep. J. Reprod. Fert. 45: 2936.CrossRefGoogle Scholar
Harrouni, M. 1977. Etude de quelques paramètres de reproduction chez la brebis de race D'man dans son berceau. Thèse doct. vét, Rabat.Google Scholar
Land, R. B. 1970. A relationship between the duration of oestrus, ovulation rate and litter size of sheep. J. Reprod. Fert. 23: 4953.CrossRefGoogle ScholarPubMed
Land, R. B., Pelletier, J., Thimonier, J. and Mauléon, P. 1973. A quantitative study of genetic differences in the incidence of oestrus, ovulation and plasma luteinizing hormone concentratio n in the sheep. J. Endocr. 58: 305317.CrossRefGoogle Scholar
Land, R. B., Russell, W. S. and Donald, H. P. 1974. The litter size and fertility of Finnish Landrace and Tasmanian Merino sheep and their reciprocal crosses. Anim. Prod. 18: 265271.Google Scholar
Marie, M. and Lahlou-kassi, A. 1977. Etude de quelques parametres de la reproduction des brebis de race Timahdite. Hommes, Terre Eaux, Rabat 6: 2329.Google Scholar
Quirke, J. F. 1979. Control of reproduction in adult ewes and ewe lambs, and estimation of reproductive wastage in ewe lambs following treatment with progestagen-impregnated sponges and pregnant mare's serum gonadotrophin. Livest. Prod. Sci. 6: 295306.CrossRefGoogle Scholar
Rhind, S. M., Robinson, J. J., Fraser, C. and McHattie, I. 1976. Ovulation rate and embryo survival at a hormonally induced oestrus in Finnish Landrace × Dorset Horn ewes. Anim. Prod. 22: 137138 (Abstr.).Google Scholar
Ricordeau, G. 1975. Parametres de prolificite des brebis Romanov, Finnoises et Croisees. Comparaison avec d'autres races prolifiques. Journées Reck Ovine Caprine, INRA-ITOVIC 2: 3863.Google Scholar
Robinson, T. J. 1951. The control of fertility in sheep. II. The augmentation of fertility by gonadotrophin treatment of the ewe in the normal breeding season. J. agric. Sci., Camb. 41: 663.CrossRefGoogle Scholar