The features of morphological and biochemical blood parameters and linear growth of steers of different origin

Abstract

The growth of beef production is possible with an increase in the number of young cattle on rearing and fattening. In the Russian Federation over-replacement young cattle of dairy breeds are mainly used for this purpose. However, the transfer of dairy cattle breeding to industrial production technologies has led to a reduction in livestock for fattening. This raises the question of the development of specialized beef cattle breeding and the increase in the number of beef cattle. The purpose of the work was to study the features of morphobiochemical indicators of blood and linear growth of beef steers of diff erent origin. The data on the results of hematological studies of Aberdeen-Angus steers and their crossbreds with Black-and-White breed have been presented in the paper. The changes in the shaped elements and biochemical parameters of the blood by the periods of rearing steers were analyzed. It was found that crossbred animals had higher rates than their purebred herdmates. A higher content of erythrocytes and hemoglobin was observed in crossbred young animals. This indicates more intensive redox processes occurring in the body and its respiratory function, which corresponds to the increase in productivity. It was found that with the age of animals in the experimental groups, there was the decrease in the blood level of hemoglobin and erythrocytes with slight fl uctuations in leukocytes, which is a common biological pattern of growth and development of animals. With a higher level of albumins in the blood, the average daily weight gain was also higher. At 3 months of age, crossbred steers had the highest average daily gains in live weight. They had by 2,3 % higher albumin content than purebred herdmates. A comparative evaluation of the linear growth of experimental steers of the beef productivity direction revealed certain diff erences in the main measurements and conformation indices; a tendency to improve beef forms in crossbred animals was noted.