Non-enzymatic antioxidants concentration and lipids peroxidation level in milk from cows with subclinical mastitis.

Abstract

Mastitis is the inflammatory reaction of the udder to invading pathogens, characterized by pathological changes in the mammary tissue, an increase in the number of somatic cells, physical, chemical and microbiological changes in the milk. We have investigated the relationship between somatic cells counts (SCC) and the concentration of antioxidant vitamins (retinol and α-tocopherol), the degree of oxidative degradation of lipids and caseins concentration. Increasing the number of somatic cells has the effect of decreasing concentration of vitamins studied. A normal SCC was correlated with the content of retinol 17.26 ± 0.86 respectively α-tocopherol 63.6 ± 3.08 μg/ml. A SCC number greater than 500.000/ml determine a decrease in retinol concentration, the average value 13.87 ± 0.90 μg/ml and the decrease in α-tocopherol concentration, the average values 50.27 ± 1.27 μg/ml. Total protein content and the proportions of casein and whey protein in total protein undergo significant changes, even when sub clinical mastitis was only slight. Dropping antioxidants concentration is correlated with an increase in oxidation processes at the level of lipids, particularly fatty acids, as demonstrated by the increasing concentration malonildialdehyde (MDA - peroxidation final product).