The sustainability and improving ofmilk production and the profitability ofsmallholder dairy units require ntegrated assessment ofreproductive performance. The purpose ofthis study is to identify reproductive performance, and genetic and non-genetic factors affecting the performance of Kurdi crosses with Holstein and Brown Swiss, developed in recent years, under rural smallholder management. The cross breeding data were related to 210 herds, 885 cows and 970 calving intervals from two calving periods of 1998
2001 and 2004
2007. The traits ofinterest were age at first calving (AFC), days open (DO), gestation length (GL) and calving interval (CI). The means ofAFC, DO, GL and CI were 28 months and 113, 277 and 390 days for crossbreds. In contrast to the sire breed, exotic gene percentage significantly influenced all traits (pB0.01). DO, GL and CI were tested and no significant differences were found for the regions and calving periods. Season of calving significantly influenced next DO (pB0.05) and GL (pB0.01). Parity number had significant effect on next DO, GL and CI (pB0.01). DO and CI have relatively desirable values in B75% crosses; on the contrary, ]75% crossbreds have unacceptable means for these traits. For upgrading to ]75%, the appropriate management practices (housing, nutrition and reproduction) must be considered to reduce postpartum anoestrus and service periods. Moreover, some research to determine more effective factors on DO must be conducted.

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