Activity of neutrophils in the blood of healthy and mastitic cows

The purpose of the study was to evaluate the metabolic activity of neutrophils in pure blood healthy and mastitic cows. Examinations were performed on 10 cows with clinical mastitis, 10 with subelinical mastitis and 10 healthy cows. The blood samples were collected from the coccygeal vessels and milk veins on the first day of clinical mastitis treatment with an intramammary product containing amoxicillin, clavulanic acid and prednisolone (or observation of the other cows) and on 3(rd) and 7(th) days. The blood was examined in the following ways: without in vitro stimulation and in vitro stimulation using fMLP, OZ, PMA. The reactive oxygen species (ROS) production was assessed by means of luminol-enhanced chemilumineseence (CL) using a kinetic method for 40 minutes at 38 degrees C, measuring CL at 5 minute intervals (BioOrbit 1251 Luminometer). The area under the curve (integrate) was calculated. Significant differences in CL levels between peripheral blood and blood flowing from the udder were not found, irregardless of the use of stimulators or udder health status. The spontaneous and induced CL level, mainly through means of the receptor, was significantly higher in the blood of mastitic cows in comparison to healthy cows. PMNs from chronic mastitic cows were characterized by weakness of oxygen metabolism and a crucial increase of a stimulated respiratory burst through activation of the protein kinase C way (PMA). A significant decrease of OZ stimulated and non significant decrease of PMA stimulated CL was determined on the 3(rd) and 7(th) days after intramammary clinical mastitis treatment; however, the spontaneous CL remained on the same level.