The Effect of spp., spp. and Enterobacteriaceae on the Development of Whey Protein Levels and Oxidative Stress Markers in Cows with Diagnosed Mastitis.

Mastitis is one of the most common diseases of high-yielding dairy cows, and over 90% of cases are caused by spp., , or spp. Certain groups of proteins are very significant in terms of the cow's antioxidant, bacteriostatic, and germicidal properties: lysozyme (Lz), lactoferrin (Lf), and β-lactoglobulin (BLG). This study aimed to determine the influence of spp., spp., and Enterobacteriaceae on the secretion of bioactive whey proteins and oxidative stress markers. From the herd, 60 multiparous cows with diagnosed mastitis were selected. Samples were taken individually from each quarter and pooled, which gave 60 samples. did not affect the BLG synthesis, whereas lysozyme and lactoferrin responded to a high concentration of these bacterial strains. In the case of spp. infection, the BLG level increased. These strains did not affect the levels of di-malonic aldehyde (MDA), lactoferrin, and lysozyme. In contrast, they were significantly influenced by spp. In summary, the levels of whey proteins and oxidative stress markers changed depending on the bacterial strain inducing inflammation. Lysozyme and lactoferrin may be markers of udder inflammation caused by and spp., whereas β-lactoglobulin may prove useful in diagnosing spp. induced mastitis.