Improved agar plate assays of bovine lysozyme and haemolytic complement activity

Bovine serum and colostral whey samples were examined for lysozyme and haemolytic complement activity, employing agar plate techniques. The tests were carried out in agarose gel containing Micrococcus lysodeikticus (for lysozyme), and antibody sensitized rabbit erythrocytes (for complement), respectively. The confirmation of lysozyme (E.C.3.2.1.17) — dependent lysis has been presented elsewhere (Lie & Syed 1986), while heat-inaotivation and antibody to C3 were used in the present study to confirm that the haemolytic activity was attributable to the complement cascade. Repeatability and sensitivity of the described tests were found to be superior to those of photometric procedures. Staining and preservation techniques were developed which extended the applicability of the assay, as they made reading of results independent of time and resulted in the plates being very suitable for photography and storage.