Indian Journal of Comparative Microbiology, Immunology and Infectious Diseases
Year : 2008, Volume : 29, Issue : 1&2
First page : ( 17) Last page : ( 22)
Print ISSN : 0790-9320.

Studies on Immunomodulatory effect of levamisole and stressroak in chicks vaccinated with different Newcastle Disease (ND) vaccines

Basu S., Singh S.D.*, Dhama K.

Avian Diseases Section, Division of Pathology, Indian Veterinary Research Institute, Izatnagar - 243 122 (U.P.)

*Corresponding author: e.mail - sdsingh2005@rediffmail.com

Abstract

A study was carried out to assess the immunomodulatory effect of Levamisole and Stressroak in chicks vaccinated with different Newcastle Disease (ND) vaccines viz. live RDF, live RDF in-oil and live RDF + killed R₂B-in-oil. Two promising immunomodulators i.e. Levamisole and Stressroak were used to study their role in further enhancement of immune response. The humoral antibody levels as detected by HI and ELISA appeared significantly higher in live RDFin-oil and live RDF + killed R₂B-in-oil groups with or without immunomodulators at different weeks post-vaccination (wpv) compared to live RDF vaccine groups. The cell-mediated immune (CMI) response, studied by lymphocyte proliferation assay, revealed that the mean stimulation indices (SI) of peripheral blood lymphocytes (PBLs) subjected to non-specific Con-A stimulation in all the vaccinated groups appeared significantly higher than the control group on 2^nd, 3^rd, 4^th and 5^th wpv, thus suggesting better efficacy of oil-adjuvanted vaccines to enhance the CMI response in chickens. The vaccine groups treated with Levamisole or Stressroak showed better mean SI values in comparison to vaccine alone groups suggesting the immunopotentiating effect of Levamisole and Stressroak on CMI response. Challenge study revealed that the live RDF vaccine protected the birds completely upto 4^th week of age but not till marketing age (6–8 weeks), while oil-adjuvanted vaccine groups with or without immunomodulators offered a complete protection against virulent RD virus till 8^th week of age and also revealed refractivity of birds to multiplication of virus. Thus in an overall assessment, livze RDF-in-oil is deemed superior and there was an added enhanced immune response with immunomodulators.

Top