The data from six flocks of Balouchi sheep from two grazing systems, namely, rangeland (R) and rangeland plus farm Residue (RF), were used to determine the effect of body size of ewe on several reproduction traits, at the
semi arid conditions of Yazd province. The traits include weight(BW), weaning weight per ewe joined (WW fFJ), weaning weight per ewe lambing
(WWIEL), ratio of the weight of lamb(s) weaned to metabolic weight of ewe at joining(WWIMWO.75J), and ratio of the weight of lamb(s) weaned to metabolic weight of ewe at lambed (WW/MWO.75L), percent ewe lambing per ewe joined (ELfFJ), percent Jamb weaned per ewe joined (L WiEJ) and per ewe lambed (LWIEL). Ewes were classified into six weight groups of five kg
intervals in order to analyse the effects of grazing systems, flocks within each system, year, age and body size of ewe. Least square mean diffrences for WWfFJ and WWIMWO.75J were non-significant in the two grazing systems, but BW was significantly greater in RF system than in R.The least square means for WWIEL and WW/MWO.75L were significantly higher in sheep raised at R than RF (P
the RF system (P
production and reproduction traits were significant between years (P
between the least square means of ewe age groups was significant
(P
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