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Biochemical and hormonal characteristics of peripheral blood in bulls in relation to genotype
1University of Technology and Life Sciences, Faculty of Animal Breeding and Biology, Department of Animal Physiology, Mazowiecka 28, 85-084 Bydgoszcz, Poland. bglow@utp.edu.pl
Abstract:
The study aimed at investigating differences in selected peripheral blood biochemical parameters and hormones in bulls of various genotype: Polish Holstein-Friesians (PHF; group I) and crossbreeds obtained from PHF dams sired by Limousin bulls (LMxPHF; group II). The blood for analysis was taken from the jugular vein twice. In blood serum the content of glucose, total protein, albumin, urea, total cholesterol, HDL, triglyceride, AST and ALT activity were determined. Insulin, triiodothyronine (T3) and thyroxine (T4) concentrations were also evaluated. The results showed that the insulin concentration and aspartate aminotransferase activity (AST) was significantly different (P<0.05) in both of the animal groups therefore it may be associated with bull genotype. Changes in triglyceride and urea levels were unclear thus long-term observation would be necessary to precisely interpret the relationships between blood serum parameters and bull genotype.
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