Establishing the immune status of poultry flocks against Newcastle disease in commercial poultry raising
Sŭrtmadzhiev, K.; Gerganov, G.; Kolarova, B.
Veterinarno-Meditsinski Nauki 17(5): 25-31
1980
ISSN/ISBN: 0324-1068 PMID: 6165132 Document Number: 158680
An experiment was carried on 133 grown up fowls and broilers from 4 industrial farms, vaccinated with spray lento and mesogenic vaccines for straining the immunity against pseodopest through RIHA and provoking pseudoplague with a pathogenic virus. A high degree of resistance was proved (94.8%), in spite of the fact that about 30% of the fowls investigated, showed low titres with regard to RIHA. Negative results with regard to RIHA were proved in 18% out of the mass counts of 3.572 blood serums of the vaccinated fowls. Attention is called to the fowls vaccinated against pseudoplague, serologically negative through RIHA, which hinder the assessment of the immune state of the fowl flock or the possibility to be potential virus-carriers during the infection with a pathogenic virus of pseudo-pest. The possibilities of the precipitation reaction in agar gel are also pointed out, both for the assessment of immunity against pseudo-pest and for the detection of a latent pseudo-pest infection in vaccinated fowl flocks.