A total of 15 pigeon samples were randomly collected during summer 2007; from Moshtoher village, kalubia province, Egypt; from an outbreak in pigeon loft suffering from nervous manifestations. Polling of trachea, lungs, liver, spleen, heart, brain and kidneys for each bird were done. Newcastle disease virus (NDV) was detected and confirmed in 3/15, 5/15, 3/15, 3/3 and 12/15 of this field samples, as well as; 6/15, 9/15, 15/15, 15/15 and 15/15 of its corresponding inoculated allantoic fluid (AF) by electron, immuno electron microscopy, hemagglutination (HA), hemagglutination inhibition (HI) and reverse transcription polymerase chain reaction (RT-PCR) assays respectively. One isolate (highest HA titer) was tested for: challenge in pigeons and chickens, infectivity titration to obtain infective dose 50% (ID50), and pathotyping by mean death time (MDT) in embryonated chicken eggs. The infected birds developed noticeable Newcastle disease (ND) clinical and necropsy signs, 108.4 EID50 /0.1ml was achieved, while; the MDT value obtained was < 60 hours. The NDV was found to be velogenic; highly virulent isolate. The results of the present study indicated that ND should be suspected in pigeons whenever sudden deaths and nervous signs were recorded. Simple, fast, cheap, reliable and effective methods for diagnosis of NDV from infective materials are varied according to the infrastructure and viable equipments of the lab |
