الفهرس 
Introduction and aim of the work
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Abstract
The present study was concerned with the study of genetic. parameters of reproductive performance twolocal Egyptian breeds of sheep. The 5066 records of 1127 Rahmani ewes and 3740 of 830 Ossimi ewes were collected over the period from 1970 to 1984 from five flocks raised at different experimental farms of Ministry of Agriculture. The data were analyzed using the mixed model techniques including the effect of location, parity, block and season and the interactions between location and parity, block and season and between season and block and parity as fixed factors and the sire within location and the ewe within sire within location as random factors.
Fertility traits were ewe conceived per ewe joined (ECj), lambs born per ewe joined (LBj), lambs weaned per ewe joined (LWj), kilograms born per ewe joined (KBj) and kilograms at four month per ewe joined (K4Mj), while prolificacy traits were lambs born per ewe lambing (LBL), lambs weaned per ewe lambing (LWL), kilograms born per ewe lambing (KBL) and kilograms at four month per ewe lambing
(K4ML).
The overall least squares means for fertility traits (ECj, LBj, LWj, KBj and K4Mj) were 0.75, 1.00, 0.88, 3.22kg and 13.59kg, respectively, in Rahmani ewes, and 0.80, 0.99, 0.85, 3.04kg and 13.62, respectively, in Ossimi ewes. The estimates of prolificacy traits (LBL, LWL. KBL and K4ML) were 1.35, 1.18, 4.35kg and 18.45kg, respectively, for Rahmani, and 1.23, 1.08, 3.89kg and 17.40kg, respectively, for Ossimi.
The effect of location was significant on all reproductive traits except on ECj and KBj in Ossimi ewes, while it was non-significant on all traits with the exception of KBL in Rahmani.
Parity was found to be of highly significant effect on all fertility traits in both breeds, while in prolificacy traits it had a highly significant effect on all traits in Rahmani and only on LWL and K4ML in Ossimi. Similar trend of increased ewe performance until the 5th to 6th parity for the fertility traits and until 7th to gth parity for prolificacy traits was found.
The effect of year, expressed as block of two years was highly significant on all fertility and prolificacy traits with the exception of LBL in the two breeds.
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