Division

Rabbit antisera to 146S antigen of seven types of foot-and-mouth disease virus (FMDV) used at a predetermined optimum concentration in carbonate/bicarbonate buffer, pH 9,6. Antigens are prepared from selected strains of virus grown on monolayers of BHK-21 cells. The unpurified supernatants are used and pretitrated according to the protocol but without serum, to give a dilution which after the addition of an equal volume of PBST (phosphate buffered saline containing 0,05 % Tween-20 and phenol red indicator) would give an optical density reading of between 1,2 and 1,5. The viruses can be used inactivated. PBST is used as a diluent. Guinea-pig antisera are prepared by inoculating guinea pigs with 146S antigen of each serotype. A predetermined optimum concentration is prepared in PBST containing 10 % normal bovine serum and 5 % normal rabbit serum. Rabbit anti-guinea-pig immunoglobulin conjugated to horseradish peroxidase is used at a predetermined optimum concentration in PBST containing 10 % normal bovine serum and 5 % normal rabbit serum. Test sera are diluted in PBST.