Comparative characteristics of biochemical parameters in wild and commercially bred foxes (Vulpes vulpes L., 1758) using PCA and correlation analysis methods

A comprehensive study of the biochemical profile of wild and commercially bred foxes (Vulpes vulpes L., 1758) of different colors (silver-black and red Ognevka Vyatskaya) was carried out using the methods of principal components (PCA) and correlation analysis. The analysis revealed significant metabolic differences between the groups related to the effects of domestication and sexual dimorphism. The PCA method showed that the factor structure of biochemical parameters in wild foxes is more distributed (82.1 % of the variance is explained by three components), whereas consolidation of metabolic processes is observed in bred on industrial fur farms, especially red Ognevka Vyatskaya foxes (up to 70.1 % of the variance in the first component). Specific associations were found in wild individuals: positive AsAT loads with creatinine (rs = 0.823; p<0.01) in females and a strong positive correlation of AsAT with albumin (rs = 0.985; p<0.01) in males, reflecting adaptive mechanisms in natural populations. Foxes bred on industrial fur farms demonstrate a more orderly metabolism with strong correlations between liver enzymes (ALT-AsAT: rs = 0.975; p<0.01 in red females). The difference in nitrogen metabolism is particularly significant: in wild females, a unique negative correlation of urea with creatinine (rs = -0.891; p<0.01) was found, whereas in animals bred on animal farms, these parameters are positively related. The study confirms that the process of domestication leads to the reorganization of metabolic networks, reducing their variability and enhancing the integration of key physiological parameters. The revealed differences reflect the adaptation of wild foxes to changing natural conditions and the specialization of individuals bred on industrial animal farms in a stable environment of maintenance and feeding. The data obtained are important for understanding the physiological consequences of animal domestication and can be used in developing criteria for assessing the status of animals bred on specialized animal farms.

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