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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
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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

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References

REFERENCES

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