Immune responses to inactivated oil adjuvanted Equine Herpes Virus-1 using different emulsifiers in horses

42-46Immune responses to formalin inactivated, oil adjuvanted equine herpes virus-1 (EHV-1) using Tween-80 (OET-80) and mannide monooleate (OEMM) emulsifiers were compared with a killed EHV-1 commercial vaccine in the three groups of EHV-1 seronegative Kathiawari horses. Each group of horses (n=3) was immunized with three doses each of the OET-80, OEMM and commercial vaccine. The complement fixation test (CFT) and virus neutralization test (VNT) were used to measure antibody levels in these horses. Mild complement-fixing (CF) antibody responses were observed after primary immunization with all the three products. Nearly 4-fold rise in CF antibody response after first booster in horses was seen up to 5, 6 and 9 weeks with OET-80, commercial vaccine and OEMM, respectively. Second booster CF antibody response was also seen in all the three groups. After primary immunization, VN antibody response was noticed in all the three groups. However, first booster injection of commercial vaccine, OET-80 and OEMM increased nearly 4-fold rise in VN antibody titre; which lasted up to 7, 9, and 12 weeks, respectively. VN antibody titre obtained after first booster injection of OEMM in horses was significantly higher (P≤0.05) as compared to OET-80 and commercial vaccine. After second booster injection rise in VN antibody titre was also observed in all the three groups of immunized horses. Control group of horses did not show any CF and VN antibodies responses. OEMM produced better CF and VN antibody responses than OET-80 and commercial vaccine