الفهرس 
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Abstract
Avian influenza virus subtype HPAI H5N1 was isolated, identified, confirmed by NAMRU-3 and
reported to the gene bank under No. EF042622.A formalin oil inactivated AI vaccine from the field
strain was prepared in SPF chicken eggs and tested for sterility, safety and immuno-genicity
according to OIE manual (2004). Immunogenicity of the prepared vaccine was compared with
imported H5Nl and H5N2 imported vaccines in 7 weeks negative layer type chickens. The higher HI
titers in imported can be attributed to the type of inactivator, antigen mass and oil adjuvant. Saponin
proved to improve immune response to both prepared and imported vaccines. Effect of dose and age
of vaccination on immune response of layer and broiler chicks was carried out and pointed out that
low HI antibodies levels were in a dose of 0.25 ml/bird inactivated AI-H5N1 or H5N2 at 1, 7 or 21
days, dose of 0.5 ml was better. AI vaccination at 7 days of age showed the earlier and higher titres
than vacCination at 1 day or 21 days. Vaccinations with H5N2 produce more hornoqenous titres but
lower than H51’J1. Birds received two full doses of H5N1 or H5N2 or H9N2 vaccine showed higher HI-
titres than one dose. Broiler chicks having high maternal antibodies are bad antibody producer to AI
vaccines which had no marked effects on body weight gains between vaccinated groups. The field
results showed that the full 3 vaccinal doses till 20 weeks increased titres from 4.00 ± 1.29 to 6.56
±1.18 ,which remained high stable and homogenous till the 40th week. There is a decline phase at
age of 25-40 weeks (maximum egg production). Three doses of AI-H9N2 vaccine, at age of 1, 7 and.
16 week of age induced high and homogenous HI and ELISA titres. ELISA positive samples ranged
from 93.33% (mean titre range 4580 ±4232 to 8292 ± 7885). It can be concluded that results of
both tests are correlated. Results of breeder and progeny H9N2 HI antibody titres in breeder ~7.47
± 0.88 all samples were positive and progeny showing titres range 4.87 ± 0.35 and 6.33 ± 0.48.
ELISA positive breeder samples in rate of 100% with antibody titres of 11117 ± 5154 or greater 90%
of the 1 day old chicks’ samples were positive with variable means 4706 ± 4673 to 14091 ± 4740.
Comparing results of HI and ELISA tests on sera of broiler chickens vaccinated with AI H9N2 vaccine
has some sort of positive relation between the results of the two tests. The detected HI (4.73 to 3.60)
and ELISA (13875 to 5708) antibody titres were decreased to half its original level within 6 - 9 days.