BLOOD PHOSPHOLIPIDS AND MUSCLE PROTEIN AS SENSITIVE BIOMARKERS OF T-2 MYCOTOXIN TOXICITY IN COMMON CARP (CYPRINUS CARPIO L.)

T-2 mycotoxin, a highly toxic trichothecene produced by Fusarium species, poses a significant threat to aquaculture due to its stability and prevalence in contaminated feed. This study aimed to evaluate the effects of dietary exposure to T-2 toxin on total lipid and protein levels in the blood and muscle tissues of common carp (Cyprinus carpio), focusing particularly on the interrelationships between biochemical parameters and their potential as biomarkers of toxic stress. Fish weighing 250-300 g were exposed to T-2 toxin at a concentration of 0.25 mg/kg of feed (five times the maximum permissible concentration) for 14 days under controlled laboratory conditions. Total lipids, phospholipids and total protein levels were determined using standard biochemical methods. Statistical analyses included Student’s t-test, Cohen’s d effect size, Pearson’s correlation and linear regression. The results revealed significant metabolic disturbances induced by T-2 toxin. Total lipids, phospholipids and protein levels in the blood were significantly reduced (p < 0.05), with particularly strong effects observed for phospholipids (Cohen’s d = 4.95). In contrast, muscle tissue exhibited a significant increase in total lipid content (p = 0.033), accompanied by a marked depletion of protein (p < 0.001; Cohen’s d = 6.51). This indicates a shift towards lipid accumulation and protein catabolism. Correlation analysis revealed coordinated metabolic regulation in the blood, with strong positive correlations between all parameters. In contrast, muscle tissue showed disrupted metabolic integration, including a strong negative correlation between lipids and protein (r = −0.72). Regression analysis confirmed that lipid levels significantly predicted protein depletion in muscle tissue (R² = 0.52), while phospholipids were strong predictors of protein concentration in blood (R² = 0.66). Thus, T-2 toxin exposure resulted in pronounced and tissue-specific metabolic alterations, characterised by systemic depletion of circulating biomolecules and local metabolic imbalance in muscle tissue. Blood phospholipids and muscle protein emerged as highly sensitive biomarkers of T-2 toxicity. These findings provide new insights into the mechanisms of mycotoxin-induced metabolic disruption in fish and highlight the importance of integrated biochemical and statistical approaches for early detection of sublethal toxic effects in aquaculture.