[Properties of the contagious ecthyma virus used for vaccine production]

Experiments were carried out to establish the effect of some antibiotics and merthiolate on the vaccinal Phylaxia strain of ecthyma contagiosa. Besides, followed up was the effect of these antibiotics on concomitant microflora that had multipled in the virus suspension. Trials were also made to titrate the vaccinal strain on lambs through scarification. Titration was carried out by the method of Schmidt. Virus dilutions of 10-1 were applied following scarification on the the thighs and fore limbs of two lams. A scarified site was also left without application to check up the effect. Each treatment needed two lambs. It was found that the antibiotics nistatin, kanamycin, oxacillin, tetraolean, oleandomycin, oxitetracyclin and chloramphenicol did not lower the activity of the vaccinal virus Phylaxia. The antibiotics tested at the respective concentrations had no sterilizing effect on the crust media regard to the concomitant bacteria. It is pointed out that the method of virus treatment can be employed to determine the biologic potential of productional batches of ecthyma contagiosa vaccine.