الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Newcastle disease (ND) is highly contagious disease, caused by pigeon paramyxo virus serotype -1 (PPMV-1) is a variant of avian Paramyxo virus serotype -1 (APMV-1), causing ND in poultry and pigeons were found to be susceptible birds. This study was carried out to follow up the behavior of NDV in experimentally infected pigeons in order to determine to any extent pigeons could be a vector in ND transmission and at any extent pigeons could be immunized against the disease. The obtained results through the present study revealed that: • Tow of 40 experimentally infected pigeons with the virulent ND virus; showed signs of illness represented by off food; ruffle feather and diarrhea on the fifth day post infection. These pigeons were still alive but with under weight level. These findings indicate that the response of pigeons to NDV experimental infection was 5%. • It was found that 95% of collected samples from experimentally infected pigeons (group-1) were found to be positive to ND virus as demonstrated by HA test while 70% of collected samples of contact pigeons (group-2) were positive to ND virus by the same test. HI test was carried out on such samples to confirm that the shedding virus is ND virus revealing 87.5% and 60% positivity among samples obtained from infected and contact birds respectively. On the other side none of samples collected from group-3 (control non infected pigeons housed separately from other groups) showed positive results to ND virus. • Application of HI test on serum samples collected from pigeons by the 4th week post experimental infection with ND virus revealed antibody titers in the experimental pigeons were 11log2; 7log2 and 0 in pigeon group-1 (experimentally infected pigeons); group-2 (in contact pigeons) and group-3 (non infected control) respectively. • The use of homologous virus in HIT; SNT and ELISA, revealed that all vaccinated pigeon groups exhibited detectable antibodies by the first week post vaccination reached their peak by the 2nd month post vaccination then began to decline gradually to reach their lowest titers by the 12th month post vaccination. So, on the use of PP virus, it was noticed that specific PP antibodies were higher (in pigeons vaccinated with PP vaccine) than those non-specific antibodies induced by other ND vaccines. On the other side the use of ND virus showed that antibodies were lower (in pigeons vaccinated with PP vaccine) than those induced by other ND vaccines. • It was found that PP vaccine provided 100% protection against the homologous PP virus and 90% against ND virus (group-1) while Hitchner-B1 protected pigeons against PP virus with 50% only and 100% against ND virus while inactivated ND vaccine protected 60% of challenged pigeons against PP virus and 100% against ND virus. On the other side, non-vaccinated challenged pigeons survived PP virus with 10% only and survived ND virus with 80%. • It is preferable to use the specific PP vaccine to protect pigeons against the disease but in case of such vaccine absent; inactivated ND vaccine could be used in a preferable suggestion than Hitchner-B1 vaccine.