mtt-formazan and Poultry-Diseases

Genetic resistance of native Egyptian breeds to very virulent infectious bursal disease virus (vvIBDV) and Newcastle disease virus (NDV) was investigated in two experiments. In the first experiment, birds from four breeds (Gimmizah, Sina, Dandrawi and Mandarah) were challenged with vvIBDV. The Mandarah chickens had the lowest mortalities (10%) compared to the Gimmizah, Sina and Dandrawi chickens (55%, 35%, and 55%, respectively). Antibody response, lymphocyte response to mitogen, and bursal lesions did not clearly correlate with the mortality rates. In the second experiment, the four chicken breeds were challenged with virulent NDV. The Mandarah chickens re-emerged as a resistant breed (20%, mortality), while the Sina, Dandrawi and Gimmizah breeds were highly susceptible (85%, 100% and 100% mortality, respectively). Further studies on the resistance mechanism are warranted.

Topics: Animals; Antibodies, Viral; Birnaviridae Infections; Bursa of Fabricius; Chickens; Egypt; Formazans; Genetic Predisposition to Disease; Histocytochemistry; Infectious bursal disease virus; Lymphocyte Activation; Newcastle Disease; Newcastle disease virus; Poultry Diseases; Tetrazolium Salts

Experiments were conducted in chickens to understand the effects of oral immunomodulation. Heat inactivated M phlei, a commensal Mycobacterium and a non-specific immunomodulator, was administered orally prior to live Newcastle disease F (ND F) strain vaccination. In experimental birds it lead to an enhanced cell mediated Immune response (CMI) against the vaccine. There was a reduction in the Haemagglutination inhibiting (HI) antibodies. However, it did not affect the protection against a virulent challenge, as the protection percentage was more or less same in vaccinated birds irrespective of the M.phlei administration. M. phlei administration could not enhance the immune response to inactivated ND F vaccine administered orally. The results indicate that M. phlei favours a CMI response to orally administered live ND F vaccine. It may be of potential use in enhancing CMI against vaccines and a cheaper alternative to costlier recombinant cytokines.

Topics: Adjuvants, Immunologic; Administration, Oral; Animals; Antibodies, Viral; Antibody Formation; Chickens; Female; Formazans; Hemagglutination Inhibition Tests; Immunity, Cellular; Male; Mycobacterium phlei; Newcastle Disease; Newcastle disease virus; Poultry Diseases; Tetrazolium Salts; Vaccination; Viral Vaccines