Validity of Ascorbic Acid as Viral Inactivant for Infectious Bovine Rhinotracheitis Virus and Bovine Viral Diarrhea Virus

Abstract

he present study was devoted to assess the potentiality of ascorbic acid (vit.C) catalytic with copper sulphate as inactivator for Infectious Bovine Rhinotracheitis Virus (IBRV) and Bovine Viral Diarrhea Virus (BVDV) compared with the conventional inactivants Binary Ethylene Imine (BEI). Stock viruses suspension of the two viruses were prepared. Virus infectivity titer were 10 7.5 and 10 6.5 respectively. The (BVD) and (IBR) viruses for suspension were inactivated separately with different concentrations (0.5,1.0 and 1.5mg/ml) of ascorbic acid. The treated viruses were incubated at 37°C incubator with continuous stirring for different period of time. It was found that the ascorbic acid induced complete virus inactivation at concentration of (1.0 and 1.5 mg/ml) after (24 and 18) hrs for BVDV and after (more than 24,24 hrs) for IBRV. While 0.001 M-BEI induced complete virus inactivation within 4 and 6 hours post treatment at 37°C respectively. Safety tests were carried out for the inactivated viruses either by using ascorbic acid or BEI, both of them was proved safe when inoculated MDBK tissue culture, in mice and in rabbit revealing complete virus inactivation. This study concluded that the optimum ascorbic acid concentration for IBRV and BVDV is (1.5mg/ml) because it made complete viral inactivation for two virus with 24 hour for each virus. Further study should be focused on IBRV and BVDV ascorbic acid inactivated vaccine to envisage the animal immune response comparing with traditional method (BEI inactivated vaccine) with the presence of ascorbic acid as an immune modulator agent in its composition especially in its nano form.