Viktor I. Eremenko and Elena G. Rotmistrovskaya
Department Biological Sciences, I. I. Ivanov Kursk State Agricultural Academy, Kursk, Russia
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(Received : March 23, 2021; Accepted : May 17, 2021)
Trends of the activity of aspartate aminotransferase and alanine transferase in the blood serum of Holstein Black-and-White, Simmental, Aberdeen-Angus heifers and hybrids of the Simmental and Aberdeen-Angus breeds was studied for comparison. The experimental heifers (40 heads) were divided into four groups according to their breed and physical and gestational age. Animals were raised under the same conditions to ensure their normal growth, development and characteristic of each breed. The blood was taken aseptically from the tail vein in the morning hours before the first feeding. The blood samples were analyzed to determine the AST and ALT activity. ALT activity in Black-and-White heifers was 250.8±6.5 nkat/l, in Simmental heifers was 254.0±5.8 nkat/l, in Aberdeen-Angus heifers was 260.4±5.5 nkat/l, and in hybrid heifers was 263.0±5.7 nkat/l. By the 3rd month of pregnancy, the ALT activity in Aberdeen-Angus heifers reached 267.5±6.1 nkat/l, in crossbred heifers it increased to 270.0±6.6 nkat/l, which was significantly higher than the ALT activity in Black-and-White animals (250.2±5.5 nkat/l). At 4.5 and 6 months of pregnancy, the highest ALT activity among the compared groups was also observed
in crossbred animals. At 4.5 and 6 months, statistically significant differences were established between ALT activity in Black-and-White, Simmental, and crossbred heifers. AST activity in the first month of pregnancy was 361.5±6.8 nkat/l in Black-and-White heifers, 372.4±7.3 nkat/l in Simmental heifers, 370.5±7.8 nkat/l in Aberdeen-Angus, and 378.8±8.1 nkat/l in hybrid animals. By the 3rd month of pregnancy Simmental, Aberdeen-Angus and crossbred animals had an increase in AST activity and during this period of pregnancy, the activity of this enzyme was 375.5±8.4, 372.2±8.8 and 386.0±8.3 nkat/l, respectively. Three-month-pregnant Black-and-White heifers had almost no changes in the AST activity (360.6±8.8 nkat/l), which was significantly lower in relation to crossbred animals (P<0.05). It was identified that the activity of aspartate aminotraspherase (AST) and alanine transferase (ALT) depended on the duration of pregnancy and the breed. Higher activity of aminotransferases was found in crossbred heifers in comparison with other commercial breeds of cattle.
Key words : : Enzyme activity, Holstein, Simmental, Aberdeen-Angus, crossbred animal, heifer, cattle