Hematological indicators in heifers of different breeds

The paper presents the dynamics of morphological parameters of blood (erythrocytes,leukocytes, hemoglobin) in heifers of different breeds during pregnancy (black-and-white,Simmental and Aberdeen-Angus, crossbreeds (Simmental x Aberdeen-Angus). Theexperiment was conducted on 4 groups of heifers, taking into account the breed affiliation of10 heads in each group. To determine the number of erythrocytes, leukocytes andhemoglobin in the blood of experimental heifers, blood samples were taken before morningfeeding from the caudal vein during pregnancy (before insemination, at 3.6 and 9 months).The level of hemoglobin and erythrocytes increases slightly with an increase in thepregnancy period of heifers, regardless of the breed of the animals. In all periods ofpregnancy, the level of hemoglobin and erythrocytes was slightly higher in crossbred heifers(Aberdeen -Angus x Simmental) in relation to the compared breeds (black-mottled,Simmental and Aberdeen-Angus). The level of leukocytes in the blood during pregnancy isnot subject to significant changes in experimental heifers. There are no interbreeddifferences in the level of leukocytes in the blood.