The aim of the research is increasing the productive indicators of replacement sheep of different genotypes by im-proving the interior indicators. To conduct the research, three groups of ewe hoggs with 20 heads each were formed: 1 group – ewe hoggs born from stud rams and Akzhaik ewes (AKSHM x AKSHM); 2 group – ewe hoggs born from stud rams of the North Caucasian breed and Akzhaik ewes (SK x AKSHM); 3 group – ewe hoggs born from Kuibyshev stud ram breed and Akzhaik ewes (KB x AKSHM). Blood parameters, live weight at the age of 4 and 8 months, hair cut at the age of 8 months was studied of animals of these groups. It was found that blood parame-ters of the ewe hoggs of different genotypes have significant differences and these affect the indicators of growth intensity and hair cutting. The content of red blood cells and hemoglobin of ewe hoggs from group 3 was higher by 0.551012/l and 9.32 g/l, respectively, than of ones from group 1. The biochemical blood parameters of crossbred ewe hoggs from groups 3 and 2 at 4 and 8 months of age in terms of total protein by 2.84 and 4.73 g/l, glucose – by 0.86 and 1.02 mmol/l exceeded the results of purebred Akzhaik ewe hoggs. Crossbreds of groups 2 and 3 in the 8-month age were superior to their herdmates of Akzhaik breed in live weight by 3.04 and 2.74 kg, and the washed wool cut – by 0.18 and 0.24 kg, respectively.