Krvna slika kod krava u peripartalnom periodu i odnos prema pokazateljima metaboličkog stresa

Lactation and metabolic rearrangement significantly influence hematological parameters. The red bloodline of early lactation cows is characterized by hypochromic changes in erythrocytes and a reduced number of erythrocytes. The reduced concentration of hemoglobin is linked to milk production, since a higher hemoglobin concentration was found in heifers (which are not naturally lactating). The number of neutrophils was the highest in the first week after parturition, while the number of lymphocytes was the lowest in the same period, so the neutrophil:lymphocyte index was the highest in this period. The number of eosinophils increased slightly during the experimental period, while the number of monocytes was thehighest in the first week and then decreased. Such changes in the differential white line occur as a consequence of the action of acute stress and a sudden jump in the concentration of cortisol, which has shown its effect on immune cells. In white cattle, NEFA as an indicator of metabolic stress leads to a drop in the total number of leukocytes, and cows classified according to the NEFA and cortisol criteria show an increased percentage of neutrophils, a decreased percentage of lymphocytes, an increased N:L ratio, a decreased percentage of eosinophils and an increased percentage of monocytes. The influence of cortisol on the parameters of the blood count only exists in the first week because the concentration of cortisol rises sharply and then sharply decreases in the first few days after calving, while the concentration of NEFA rises slightly and is often persistent in the first weeks of lactation, which indicates a negative energy balance . In the study of the influence of metabolic stress indicators on the value of the parameters of the blood count, it was found that the classification of cows according to the values of NEFA and cortisol gives significant differences in the red and white bloodlines, which confirms the importance of peripartum metabolic stress caused by parturition and lactation in the response of the blood count in cows.