Humoral factors of natural resistance of Bos indicus cattle selected for antibody titre to Brucella abortus.
The concentration of lysozyme, total immunoglobulin and bactericidal activity were measured in sera of Bos indicus cattle, retrospectively screened for specific antibodies to Brucella abortus and classified as being positive reactors or negative reactors. In addition, the effect of complement in the sera was studied to demonstrate complement dependence of antibody-mediated bacterial killing. It was observed that, under the test conditions, serum bactericidal activity and concentration of total immunoglobulin were associated with high specific antibody levels (P less than 0.001). Furthermore, there was a slight decrease in the lytic activity of lysozyme in the sera of animals with high antibody titres.
Gwakisa
P S
PS
Faculty of Veterinary Medicine, Sokoine University of Agriculture, Morogoro, Tanzania.
Minga
U M
UM
D000818:Animals; D000907:Antibodies, Bacterial / Q000032:analysis*; D001770:Blood Bactericidal Activity; D002003:Brucella abortus / Q000276:immunology*; D002417:Cattle / Q000276:immunology*; D007113:Immunity, Innate; D009113:Muramidase / Q000097:blood
D000907:Antibodies, Bacterial; D009113:Muramidase