Physiological changes in hematological parameters of black-and-white cows at the beginning of lactation

Biotech University, Moscow, Russia

^* Corresponding author: ilnyrafaizullina@yandex.ru

Abstract

The onset of lactation can affect the condition of cows, affecting the metabolic processes throughout the body and hematological parameters. The blood parameters of high-milk cows after the first and after the second calving were evaluated in the work. 47 fully healthy pregnant cows were selected 3 weeks before the expected calving. These included first-heifers and re-calving purebred cows of a black-and-white breed. The animals were divided into two groups according to the number of pregnancies available in their lives: the group of first-born heifers consisted of 22 heads, the group of re-calves included 25 heads. The examination was performed 3 weeks before calving and 3 weeks after calving with taking blood samples. The first heifers after calving showed a decrease in the concentration of glucose, total protein and albumin with a significant increase in the concentrations of malondialdehyde, non-esterified fatty acids and globulin compared with the first study. Re-calved cows showed a significant decrease in the amount of glucose, total protein and albumin in the blood, combined with a significant increase in cholesterol and malondialdehyde levels compared to their pre-calving values. In re-calving cows, a significant decrease in non-esterified fatty acids was noted in comparison with calved first-calf cows. During the transition phase, control of the main hematological parameters is necessary for the timely prevention of pathology in first-heifers and re-lost cows.