الفهرس 
Introduction
Historic emergence and EpidemiologyOnly 14 pages are availabe for public view
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Abstract
About 130 Living pigeonscollected from local markets and pigeon’s lofts in Assiut, Minia and NewValley governorates, were examined for PPMV-1, clinical signs were nervous disorders, and greenish diarrheaand the post mortem examination didn’treveal more than brainhemorrhage.
Virus isolation from the brain samples of the suspected birds were carried out through preparation of bacterial free suspension then inoculated in 9-11 days old embryonated chicken eggs (ECE) via allantoic route. To determine the hemagglutination character of paramyxoviruses, the harvested allantoic fluids were tested for hemagglutination90 samples were HA positive out of 130 collected samples(69.2%). Preliminary identification was done by hemagglutinationinhibition (HI) test using specific antiserum from chickens vaccinated only against Newcastle. The results revealed 85 samples were inhibited out of ninety HA positive examined samples with a percentage 94.4% were HI positiveactivity.
Five representative samples were processed forevaluation of pathogenicity of PPMV-1isolatesusing intracerebral pathogenicity index (ICPI) in one day old chicksand the results showed four isolates were lentogenic in virulence with score >0.7 and one isolate was mesogenic <0.7.
Molecular characterization was done for the five strains that were previously characterized by ICPI through sequence analysis for the partial F gene and the results revealed that:
i. The analysis of the deduced amino acids of (f) protein gene cleavage site for the obtained PPMV-1strains showed that all examined isolates had multibasic amino acid sequence 112KRQKRF117 at the F-gene cleavage site which indicated the belonging of the examined isolates to velogenic strains in contrast to results of ICPI that four isolates were lentogenic with value equal or less to 0,7 and one was mesogenic with value more than 0.7. This variation is considered a characteristic to a variant strain of pigeon paramyxovirus type 1.
ii. Also, phylogenetic analysis based on the nucleotides showed that the examined isolates were clustered in class II genotype VI/b isolates that were characterized and specified for pigeon paramyxovirus.
iii. The similarity index based on the nucleotides revealed that our isolates had greatest similarity with the previously characterized Egyptian isolates recovered from pigeons (pigeon-Egypt-Sharkia-2-2013-Vib-2-kx580) isolated in Sharkia 2013 and (pigeon-Egypt-Sharkia-17-2014-Vib-2-kx58) isolated in Sharkia 2014with a percentageranged from95%-96.8% and95.3%-97.5% respectively.Also, the homology index revealed high similarity with Russian isolates; (Pi-Rus-Vladimir-687-05-VIb-2-JF824032) and (Pi-Rus-kursk-0484-09-JF824028) with percentages ranged from94.7% - 97.1% and 90.7%-91.2% respectively.Proving that the isolates circulating in the area of research may be have an origin from north of Asia.
For further confirmation of the obtained results, an experimental infection in pigeons was designed.group of birds received 50μl intraocular and 50μl intranasal and the other group received50μl intramuscularof the isolated allantoic fluid.The birds were observed for clinical signs,morbidity and mortality due to PPMV-1 infection daily. Brain and liver samples were collected from diseased and dead birds and processed separately for E.C.E inoculation and the allantoic fluid tested for presence of ND antibodies using the HA and HI assay by standard methods.Pigeons showed signs of paralysis and were depressed, consumed less food and water, and displayed ruffled feathers from 4 d.p.i and onwards.All isolated samples from pigeons responded positively in the HA and HI tests, confirming that our isolates during this work are of pigeon origin and have high affinity to cause infection in pigeons, with morbidity rates ranged from (60-100%) and mortality ranged from (40-80%).