Hostname: page-component-848d4c4894-r5zm4 Total loading time: 0 Render date: 2024-06-23T02:36:49.969Z Has data issue: false hasContentIssue false
  • English
  • Français

Reproductive performance of Merin, sub-tropical Egyptian sheep and their crosses

Published online by Cambridge University Press:  27 March 2009

A. M. Aboul-Naga
A. M. Aboul-Naga
Affiliation:
Animal Production Research Institute, Minisitry of Agriculture, Dokki, Cairo, Egypt
Get access Rights & Permissions [Opens in a new window]

Summary

Ewe reproductive traits of imported Merino local Ossimi and Barki, their first crosses, backcrosses to Merino and the interbred groups of the backcrosses, were considered in this study. Records of 2168 ewes born from 1960 through 1970 were used in the study; they totalled 6959 records.

Reproductive performance was different in the three purebred groups, with more multiple births but more lamb losses and abortions in Merinos. However, the three groups weaned similar numbers of lambs/ewe run with the rams (0·98). Merino × Ossimi ewes had the best performance, they lambed and weaned 27% more lambs than local Ossimi. They were followed by MB ewes weaning 0·96 lambs/ewe run with the rams. Reproductive performance of the backcross ewes was lower than that of the first cross, but still better than the purebred groups. Inter-breeding of back-crosses reduced their hybrid vigour markedly.

Non-maternal heterosis contributed greatly to the reproductive performance of cross-bred ewes, while the effect of maternal heterosis on reproductive traits was fairly small.

Multiple births showed least heterotic effect.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 84 , Issue 3 , June 1975 , pp. 383 - 386
Copyright
Copyright © Cambridge University Press 1975

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

Aboul-Naga, A. M. (1974). Heterotic components in ewe reproduction performance of Merino crosses with sub-tropical Egyptian sheep. 1st World Congress Genetics Applied to Livestock Production, Madrid, 1974 (in Press).Google Scholar
Aboul-Naga, A. M. & Galal, E. S. (1973). A note on the effect of interbreeding among backcrosses of sheep breeds. Animal Production 16, 87–90.Google Scholar
Aboul-Naga, A. M., El-Tawil, E. E., Galal, E. S., Labban, F. & Khishin, S. (1972). The effects of crossing Merino with Ossimi and Barki sheep on some production traits. Journal Agricultural Science, Cambridge 78, 278–80.CrossRefGoogle Scholar
Coop, I. E. & Clarke, V. R. (1965). A comparison of Romney and First cross Border Leicester – Romney ewes for export lamb production. New Zealand Journal Agricultural Research 8, 188–203.CrossRefGoogle Scholar
Fahmy, M. H. & Bernard, C. S. Effects of crossbreeding and certain environmental factors on multiple births, wool production and growth in sheep. Animal Production 16, 147–56.Google Scholar
Mabrouk, M. M. (1970). Studies on the reproductive performance of sheep under coastal desert conditions. M.Sc. Thesis, Al-Azhar University, Cairo.Google Scholar
McGurik, B. J. (1967). Breeding for lamb production. Wool Technology Sheep Breeding 14, 73–5.Google Scholar
Sidwell, G. M. & Miller, R. R. (1973). Production in some purebreeds of sheep and their crosses. I. Reproductive efficiency in ewes. Journal Animal Science 23, 1084–9.Google Scholar
Turner, H. N. (1969). Genetic improvement of production rate in sheep. Animal Breeding Abstract 37, 545–63.Google Scholar