This study investigated the distribution of 40K, 137Cs and 90Sr during the processing of cow milk into cottage cheese from central Bosnia and Herzegovina and Livno cheese from the southwestern production area, with particular emphasis on physicochemical composition and regional differences. Raw milk (n = 15 per group), corresponding cheeses (n = 15 per group), and composite whey samples (one per cheese type) were analyzed for protein, fat, dry matter, water content, 40K, and 137Cs, as well as titratable acidity in milk samples. In a random second-stage subset, because of the cost and complexity of the radiochemical method, 90Sr was determined. Mean activity concentrations in milk used for cottage and Livno cheese production were 42.31 and 40.77 Bq/L for 40K, 0.030 and 0.057 Bq/L for 137Cs, and 0.015 and 0.030 Bq/L for 90Sr, respectively. Corresponding cheese means were 26.45 and 28.23 Bq/kg for 40K, 0.038 and 0.087 Bq/kg for 137Cs, and 0.073 and 0.369 Bq/kg for 90Sr. Processing retention factors showed limited transfer of 40K and 137Cs into cheese, whereas 90Sr was retained mostly in the curd. Significant regional differences were observed for 137Cs in both milk and cheese, whereas 40K did not differ significantly between regions. Differences between regions for 90Sr were also indicated, but these results should be interpreted cautiously because it was analyzed only in a limited second-stage subset. These findings show that radionuclide behavior in artisanal dairy systems is jointly shaped by radionuclide chemistry, cheese technology, and local environment, highlighting the need for site-specific food-chain assessment.

Objective: The aim of the study was to determine the possible impact of the total daily amount of skim milk on the level of bilirubin and liver enzymes through regression analysis. Materials and Methods: The study included 63 Holstein-Friesian cows. They were formed in 3 groups, based on the amount of daily milk production. Peripheral blood was punctured, through which the activities of total bilirubin were analyzed (μmol/L), as well as liver enzymes: alanine aminotransferase – ALT (U/L), aspartate aminotransferase – AST (U/L), lactate dehydrogenase – LDH (U/L) and alkaline phosphatase – ALP (U/L). Results: The lowest concentration of total bilirubin in blood plasma was recorded in the group of cows that have the lowest daily milk production (1.295 ± 0.255 µmol/L), and highest concentration is in cows that produce the most milk (1.855 ± 0.159 µmol/L), but intergroup differences are not significant. Regression analysis found a statistically significant relationship between the amount of produced daily milk and the concentration of total bilirubin (R2=0.132, p=0.0050.05). Conclusion: The activities of bilirubin and liver enzymes in the examined cows were in physiological balance. This indicates that the cows on the farm are raised in modern and good zootechnical and feeding conditions. In such conditions, dairy cows are able to maintain blood composition and homeostatic integrity within physiological limits and adequate reproductive and productive capacity.