Live vaccine against contagious ecthyma of sheep - prepd. from virus attenuated by passaging on foetal skin cells

Live viral vaccine against contagious ecthyma of sheep comprises the attenuated viral strain 'L-1' (deposition number 8). This is isolated from the infected areas of the skin of a lamb and adapted by repeated passages on a primary culture of sheep foetal skin cells. Esp. 10-20 passages on cells from a 3-3.5 month old foetus are carried out at 36-37 deg.C. The attenuated strain is grown on cells of 3-month old sheep foetal skin at 36 deg.C. pref. using medium N199 contg. 2% bovineserum for maintenance. Particularly the virus contg. material is first harvested when 50-70% of the cells are infected and the second harvest is taken 24-36 hrs. later. This vaccine is highly immunogenic, safe and free from contaminating viruses. The attenuated strain can be grown on readily available substrates and provides immunity (which lasts for at least 9 months) against a wide range of epizootic viral strains. LA PRESENTE INVENTION CONCERNE LE DOMAINE DE LA MEDECINE VETERINAIRE, ET PLUS PRECISEMENT, UN VACCIN VIRAL VIVANT CULTIVE CONTRE L'ECTHYMA CONTAGIEUX DES RACES OVINES ET SON PROCEDE DE PREPARATION.CONFORMEMENT A L'INVENTION, LE VACCIN INDIQUE CONTRE L'ECTHYMA CONTAGIEUX CONTIENT UNE SOUCHE L-1 N 8 DU VIRUS DE L'ECTHYMA CONTAGIEUX OBTENUE A PARTIR DU VIRUS DES RUES, ISOLE DANS LES ENDROITS INFECTES DE LA PEAU DE L'AGNEAU ATTEINT DE L'ECTHYMA CONTAGIEUX, ET ADAPTEE PAR PLUSIEURS PASSAGES A UNE CULTURE PRIMAIRE DE CELLULES DE LA PEAU DU FOETUS DE 3-3,5 MOIS DU MOUTON.LE PROCEDE DE PREPARATION DU VACCIN CONSISTE A CULTIVER LA SOUCHE L-1 N 8 SUR LA CULTURE DE CELLULES DE LA PEAU DU FOETUS DE 3-3,5 MOIS DU MOUTON SUR UN MILIEU D'ENTRETIEN. LA PREMIERE RECOLTE DE LA MATIERE CONTENANT LES VIRUS EST REALISEE APRES LA LESION DE 50-70 DE CELLULES DE LA CULTURE.LE VACCIN PEUT ETRE UTILISE DANS LA MEDECINE VETERINAIRE CONTRE L'ECTHYMA CONTAGIEUX DES RACES OVINES: MOUTONS ET CHEVRES.