HEMATOLOGICAL AND CYTOLOGICAL CHARACTERISTICS OF COWS WITH DIFFERENT LEVELS OF MILK PRODUCTIVITY

Abstract

The article studies the content variability of erythrocytes, leukocytes, hemoglobin, ESR index as well as numerous versions of micro-nucleus test and NOR (Nucleus Organizing Regions) Index. The studies were held for the inter-phase lymphocytes nuclei of the blood of heifers of the Ukrainian red-motley breed species that have various level of milk productivity. The studies displayed that the better the productivity do the heifers have the higher the erythrocyte and leukocyte values are. The direct and positive correlation between the milking of the cows, the level of erythrocytes and the level of hemoglobin is established. However, there was no connection found between the milk productivity level and the content of leukocytes in the blood. It is stated that the least level of erythrocytes that contain micro-nuclei is registered for the cows with a milking value of 3000-4000 kg. For the groups of cows that have the milking level of 6000 kg and above an abrupt increase of erythrocytes with micro-nuclei was detected, comparing to the groups of the lower milk productivity. The frequencies of the lymphocytes with micro-nuclei are slightly higher for the groups that have the productivity level of 3000-4000 kg of milk, comparing to the groups of productivity of 4000-6000 kg and is lower than the heifers with productivity of 6000 kg and above. By the coloration of the samples with silver nitrate it is stated that the least NOR number in inter-phase lymphocytes nuclei is applicable for the heifers with milking level of 3000-4000 kg, while the highest number is noticed for the cows of the productivity level of 5000-6000 kg. The average NOR Index among all researched groups of animals is 2.36.