الفهرس 
Chapter I : IntroductionOnly 14 pages are availabe for public view
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Abstract
The present study was designed to prepare an inactivated cell culture pigeon paramyxo virus vaccine. The obtained results revealed that :
1- PPV-1 was propagated successfully in Vero cell culture inducing mild cytopathic effect (CPE) on the 3rd to 4th day post-inoculation during the first three passages and the virus harvest was obtained by the 7th day. The detected CPE was began to start early on the first day post cell infection by the fourth passage and complete CPE was obtained by the 3rd day.
2- The cytopathic effect was characterized by cell rounding, cell degeneration and ended with cell lysis and detachment of the cell sheet.
3- The virus titer was started at low levels (3 log10 TCID50 ∕ ml) then increased gradually by serial virus passage to reach a peak titer (8 log10 TCID50 ∕ ml) by the 8th passage.
4- The growth kinetics of PPV-1 in Vero cell culture showed that there was gradual increases in the titers of cell associated virus (CAV) during the first hours post cell infection recording a peak titer (3.5 log10 TCID50 ∕ ml) by 36 then such virus titer began to decrease and the cell free virus (CFV) began to increased at the same time and reached its peak (7.5 log10 TCID50∕ ml) by 60 hours post infection. The total virus yield was increasing gradually from 1.5 log10 TCID50∕ ml 12 hours post infection to record its maximum titer (8 log10 TCID50∕ ml) by 72 hours post virus inoculation.
5- Using 3% of BEI at 37˚ C; it was found that complete inactivation of PPV-1 could be obtained by 4 hours after the starting of the inactivation process as recorded by
virus titration on hour intervals. The loss in virus titer was gradually and liner where it was 1 log10 TCID50∕ ml each half hour.
6- The prepared inactivated cell culture PP vaccine was found to be free from foreign contaminants; did not induce any abnormal clinical signs in vaccinated pigeons and protected them against the challenge with the virulent virus while unvaccinated birds showed typical signs of PP virus infection.
7- Monitoring of the induced immunity in vaccinated pigeons with the prepared inactivated cell culture PP vaccine; it was found that SNT and HI tests revealed that the vaccine was able to induce detectable levels of specific PP antibodies by the first week post vaccination (titer of 4 by SNT and 8 by HI). These antibodies were increased to reach a titer of 32 by SNT and 64 by HI on the third week post vaccination then decreased to 16 and 32 respectively after application of the challenge test. Later on; PP antibodies recorded their peak titer (128 by SNT and 256 by HI) by the first month post challenge (about 2 month post vaccination) and still unchanged up to 9 months then began to decrease gradually to reach their lowest titers (8 by SNT and 16 by HI) on the 12th month.
8- It was noticed that in field vaccinated pigeons, the induced specific PP antibodies were similar in behavior to those in experimentally vaccinated birds although they showed some what lower peak titers (64 by SNT and 128 by HI) on the second month post vaccination.