Concentration of serum amyloid A and activity of ceruloplasmin in milk from cows with clinical and subelinical mastitis

The aim of the study was to determine the concentration of serum amyloid A (SAA) and the activity of ceruloplasmin (Cp) in milk from cows with clinical mastitis of various severities and with subclinical mastitis in aspect of their usefulness for the detection of mastitis in cows. The concentration of SAA was determined using the commercial ELISA kit. The activity of Cp was determined according to the Rice et al., method. The mean concentration of SAA in milk from cows with mastitis ranged from 4.47 to 322.26 mu g/mL. The mean SAA concentration in milk from healthy cows was 11.67 (7.40) mu g/mL and was significantly lower (P<0.01) compared to that in milk from cows with the particular forms of mastitis. The activity of Cp in milk from cows with mastitis ranged from 3.00 to 18.83 U/g of protein. Both in clinical and subclinical mastitis the activity of Cp was significantly higher (P<0.001) compared to that of milk from cows with healthy mammary glands (1.20 +/- 0.42 U/g of protein). The findings revealed that both the SAA concentration and Cp activity were sensitive indicators of inflammatory processes in the udder, even those graded as mild. Their determination in milk may be a reliable and non-invasive diagnostic method to detect mastitis, particularly its subclinical form.