Newcastle disease (ND) is considered to be one of the most economically significant avian viral diseases. It has a worldwide distribution and a continuous diversity of genotypes. Despite its limited zoonotic potential, Newcastle disease virus (NDV) outbreaks in Egypt occur frequently and result in serious economic losses in the poultry industry. In this study, we investigated and characterized NDV in wild cattle egrets and house sparrows. Fifty cattle egrets and fifty house sparrows were collected from the vicinity of chicken farms in Kafrelsheikh Governorate, Egypt, which has a history of NDV infection. Lung, spleen, and brain tissue samples were pooled from each bird and screened for NDV by real-time reverse transcriptase polymerase chain reaction (RRT-PCR) and reverse transcriptase polymerase chain reaction (RT-PCR) to amplify the 370 bp NDV F gene fragment. NDV was detected by RRT-PCR in 22 of 50 (44%) cattle egrets and 13 of 50 (26%) house sparrows, while the conventional RT-PCR detected NDV in 18 of 50 (36%) cattle egrets and 10 of 50 (20%) of house sparrows. Phylogenic analysis revealed that the NDV strains identified in the present study are closely related to other Egyptian class II, sub-genotype VII.1.1 NDV strains from GenBank, having 99.7%–98.5% identity. The pathogenicity of the wild-bird-origin NDV sub-genotype VII.1.1 NDV strains were assessed by experimental inoculation of identified strains (KFS-Motobas-2, KFS-Elhamoul-1, and KFS-Elhamoul-3) in 28-day-old specific-pathogen-free (SPF) Cobb chickens. The clinical signs and post-mortem changes of velogenic NDV genotype VII (GVII) were observed in inoculated chickens 3 to 7 days post-inoculation, with 67.5%–70% mortality rates. NDV was detected in all NDV-inoculated chickens by RRT-PCR and RT-PCR at 3, 7, and 10 days post-inoculation. The histopathological findings of the experimentally infected chickens showed marked pulmonary congestion and pneumonia associated with complete bronchial stenosis. The spleen showed histocytic cell proliferation with marked lymphoid depletion, while the brain had malacia and diffuse gliosis. These findings provide interesting data about the characterization of NDV in wild birds from Egypt and add to our understanding of their possible role in the transmission dynamics of the disease in Egypt. Further research is needed to explore the role of other species of wild birds in the epidemiology of this disease and to compare the strains circulating in wild birds with those found in poultry.

The epidemiology, Pathogencity and the possible ways of treatment of Klebsiella pneumoniae (K. pneumoniae) infection as a respiratory pathogen in broiler chicken farms in different places in Gharbia Goernorate were investigated during 2014/2017.For this purpose 150 samples were collected from lung, trachea, , liver and intestine samples of 150 diseased, 1-5-week-old commercial broiler chickens suffered from respiratory disorders, diarrhea, growth retardation and mortality with pneumonia, pericarditis, airsaculitis and enlarged liver. Bacteriological examination of swabs from trachea, lung, liver and intestine revealed Gram negative, non-motile rod-shaped organisms which were commonly isolated from lung, liver, intestine and trachea. The isolation trials revealed 10 K. pneumoniae positive cases with an incidence (6.6%). Identification of the isolated strains Biochemically by API 20 E and molecularly by polymerase chain reaction (PCR) revealed that the isolates belonged to K. pneumoniae. The K. Pneumoniae isolate was inoculated experimentally in 7 dayold chicks and clinical signs, lesion were reproduced. Clinical signs& P.M lesions characteristic in K.Pneumoniae infection was reproduced when the K. Pneumoniae isolates was inoculated in 7 day old chicks.