Age-related dynamics and interrelationships of biochemical blood parameters in landrace and duronco pigs

The article presents the study results of the breed features and age dynamics of the enzyme activity - aspartate aminotransferase, alanine aminotransferase and urea in gilts of the Landrace and Duroc breeds. Significant breed differences in the biochemical status were revealed. The gilts of the Landrace breed have a relatively stable and high enzyme activity. The average alanine aminotransferase activity in Landraces was 43.8 U/L, which is 36.0% more than in Durocs. The aspartate aminotransferase content in the blood serum of Landrace gilts varied within a narrow range of 25.9 U/L to 44.0 U/L, while the Duroc showed a pronounced amplitude of changes from 42.3 U/L to 15.0 U/L, with a sharp decrease by the end of the study. The serum urea concentration increased in both breeds by the end of the study, but the dynamic pattern was different: Landrace gilts showed a smooth increase to a maximum of 5.1 mmol/L at week 16, while Duroc gilts showed a sharp decrease to 1,2 mmol/L at week 17. The average urea level in Landrace gilts was 23.3% higher. Significant breed differences in metabolism have been established. In Landrace pigs, a moderate positive correlation between transaminases (r = 0.48), no correlation between alanine aminotransferase and urea (r = 0.05), and a negative correlation between aspartate aminotransferase and urea (r = -0.33) were found. In Duroc pigs, by contrast, a single positively correlated biochemical complex was revealed: a strong correlation between alanine aminotransferase and aspartate aminotransferase (r = 0.86), as well as moderate positive correlations of both enzymes with urea (r = 0.55 and r = 0.47, respectively). The revealed features reflect breed-specific metabolic processes formed as a result of selection. The obtained data should be used in the development of biochemical markers in breeding programs.