Comparative efficacy of cryoprotectant in the lyophilization of pigeon paramyxovirus-1 vaccine

Preparation oflive attenuated freeze dried Pigeon Paramyxo Virus-1 (PPMV-1) vaccine selection ofproper cryoprotectant which could preserve and protect the virus against injury due to reduction of temperature at the time of lyophilization, was very necessary. PPMV-1 locally isolated lentogenic strain was selected as seed virus which was properly attenuated by serially passaging in 9 to 10 days old embryonated specific pathogen free (SPF) fowl eggs and produced master seed virus and working seed virus. Five per cent lactalbumin hydrolysate with 10% sucrose (LAS) and 1% polyvinyl pyrrolidone (PVP) were used as two different cryoprotectant for lyophilization of working seed virus. After lyophilization value of haemagglutination (HA) titer and embryo infective dose fifty per ml (EID₅₀/ml) were changed and concluded that both LAS and PVP could be used as suitable cryoprotectant where LAS was better than PVP which was first time done in the whole world.