Thumbnail Image

Theses (PG)

Browse

20182
Reset filters
Subject: Veterinary Microbiology × Start date: 2006 × Thesis Type: Ph.D ×
Reset filters

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    ThesisItemOpen Access
    CONSTRUCTION OF Brucella melitensis GHOST AS A VACCINE CANDIDATE AGAINST BRUCELLOSIS
    (KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDA, 2018-07) SUMATHI, B. R; B. M. VEEREGOWDA
    he present study reports the usefulness B. melitensis ghost as a vaccine candidate against sheep and goat brucellosis. An overall seroprevalence of 36.36 per cent (200) by RBPT, 47.27 per cent (260) by c-ELISA and 36.36 per cent (200) by both the tests with highest seroprevalence of 56 per cent in Bengaluru rural for sheep and of 43 per cent in Kolar for goats was observed. On an isolation from aborted foetuses five Brucella spp. were recovered which were confirmed to be B. melitensis biotype 1 by biochemical tests, dye sensitivity tests, agglutination with monospecific serum and by genus specific, species specific and Bruce ladder PCR. The B. melitensis Rev 1 and B. melitensis field isolate ghosts were constructed at a cell concentration of 3.0 x 10 9 CFU/mL of culture with 80 μg/mL GI24 for complete ghost formation was confirmed by absence of growth on BSA, non amplification of specific bands in AMOS multiple PCR and morphological changes observed in scanning and transmission electron microscopy. All three vaccines, were evaluated in mice by IP and oral routes, for humoral immune response by quantifying IgG levels in post vaccinal sera and for cell mediated immune response by lymphocyte proliferation assay and cytokine profiles of IL-10, IL-4, TNF-α and IFN-γ. There was a significant difference in IgG levels between control and vaccinated groups. Further, within the vaccinated groups there was a significant (P<0.05) difference between Rev 1 vaccinated group from Rev 1 ghost and field ghost vaccinated groups in both IP and oral routes. The serum IgG levels were significantly higher in Rev 1 IP route vaccinated group than other groups. There was an interplay of both Th2 (IL-4 and IL-10) and Th1 cytokines (TNF–α and IFN-γ) in eliciting effective immune response, wherein initial response was dominated by Th2 through IL-4 and IL-10 which antagonize the TNF–α and IFN-γ cytokines whose role is very essential to initiate cell mediated immune responses. In later stages decreased levels of IL-4 and IL-10 resulted in surge of TNF–α and IFN-γ cytokines resulting in effective Th1 mediated cellular immune response which is required for effective clearance of Brucella organisms. The ghosts made from B. melitensis Rev 1 and field isolate performed equally well as B. melitensis Rev 1 by eliciting an effective immune response and protecting mice against B. melitensis 16M challenge.
  • Thumbnail Image
    ThesisItemOpen Access
    DEVELOPMENT AND EVALUATION OF INACTIVATED Mycobacterium avium subspecies paratuberculosis VACCINE IN SHEEP
    (KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR, 2018-07) RAMESHA, C. B.; Dr. D. RATHNAMMA
    The present study was undertaken to evaluate autogenous inactivated MAP vaccine of sheep origin with inactivated MAP S5 vaccine of goat origin in Mandya breed of sheep. The clinical symptoms attributable to JD were not observed in any of the vaccinated animals, whereas unvaccinated animals showed progressive loss of body weight, emaciation, weakness, pasty diarrhoea and rough hair coat after 90 days post vaccination (DPV). In Lymphocyte transformation test, PBMCs from the vaccinated animals had higher stimulative index. In serum nitric oxide assay, more of serum nitric oxide was observed in vaccinated animals. In serum IFN γ assay, vaccinated animals had significantly higher level of IFN γ. All three groups of animals showed peak levels at 90 DPV and maintained up to 180 DPV. Indirect ELISA results revealed that vaccinated animals had significantly higher antibody levels. Both the vaccines successfully inhibited localization of MAP in the intestine and in turn faecal shedding of MAP was significantly low in vaccinated animals up to 300 days. The shedding of MAP increased steadily after 90 days post challenge in control animals. Vaccinated animals remained healthy and gained significantly higher body weights compared to control. Gross and microscopic lesions were not observed in vaccinated animals, control animals showed thickening and corrugation of small intestine and enlarged lymph nodes, infiltration of mononuclear and epitheloid cells in intestine and lymph nodes. None of the vaccinated animals were positive for AFB. Further 33.33 per cent unvaccinated challenged animals were positive for AFB. Whereas, 16.66 per cent vaccinated and 50 per cent unvaccinated animals were positive for MAP antigen by immunohistochemistry. The CD4+ and CD8+ T cells in lymph nodes by immunohistochemistry revealed high concentration of CD8+ cells in vaccinated animals. There was no significant difference in expression of CD4+ T cells. Both inactivated MAP vaccines had elicited cellular and humoral immune responses and effectively inhibited the localization of MAP.