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Fifty broiler chicks were divided into five groups to study the antiviral and immune-stimulant effect of Allium cepa essential oils (ACEO). The effect of Allium cepa essential oils administration single or combined with NVD vaccine in broilers, more than one parameter was studied in this study i.e., the clinical symptoms that appeared on the chicks after the experimental infection with velogenic Newcastle disease virus, postmortem lesions, pathological lesions scoring, mortality rate (MR), and viral shedding, birds immunity was assessed by HI test and protection percent post-challenge with vNDV. Our result showed that mild clinical signs, lesion scoring, decreased viral shedding in ACEO treated groups 3 (G 3) more than control groups post-challenge with vNDV. Delayed onset of mild clinical signs in G3 followed by complete recovery 7th-day post-challenge (DPC). Low MR (40 and 0%) and high protection percent (100 and 60%) in ACEO treated G3 and G5, respectively. spleen, thymus, cecal tonsil, proventriculus, and cerebrum lesions scoring in G3 and G5 were significantly ((p ≤ 0.05).) lower than the control group, proving a decrease in NDV replication and effective antiviral activity of ACEO. HI titer significantly increased (p ≤ 0.05) In G3, G4 and G5 compared with control groups. There is no significant difference in HI titer in ACEO treated groups and vaccinated groups. In conclusion, oral administration of ACEO combined with NDV vaccines significantly reduces or eliminates lethal clinical signs, lesions, viral shedding, and enhances immune response and protection percent after vNDV challenge proving the natural antiviral and immune stimulant effect of ACEO onion extract. Implementing such a regime might aid NDV control in broiler flocks in endemic areas and reduce the epidemiological load of NDV in the environment. more...

Colibacillosis is a complicated disease causing severe economic losses and challenging veterinarians and producers. Therefore, this study aimed to characterize avian pathogenic Escherichia coli (APEC) strains causing respiratory troubles in chickens. Thirty broiler chicken flocks (2013-2016 outbreaks) at age of 17-35 days from Sharkia, Ismailia, Dakahlia and Sinai showed respiratory troubles and greenish diarrhea. The postmortem findings revealed typical colisepticemia picture including air sacculitis, fibrinous pericarditis and perihepatitis. The percentage of APEC isolation was 100 % while 10 flocks suffered mixed infections. From 284 collected samples (air sacs, heart blood, lungs and liver), E. coli isolation was mostly from air sacs (76.1 %) and lung (73.2 %) followed by heart blood (67.6%) and liver (54.9%). Based on serogrouping, the most common serogroups were O78 and O2 with percentage of 15% each. Based on antimicrobial disc diffusion test, the lowest (32.7 %) and highest resistance (100 %) were to doxycycline versus lincomycin, spiramycin, oxacillin and amoxicillin. PCR analysis for 55 MDR E. coli isolates revealed 3 antibiotic resistance genes (blaTEM (87.3 %), blaCTX-M (85.5 %) and blaOXA (5.5 %)) and 6 virulence genes in two multiplex PCR (iucD (96 %), Fim H (92.7 %), iss (76.4 %), ompT (58.2 %), tsh (45.5 %) and cvaC (9 %). An association between virulence and multidrug resistance genes in E. coli was concluded, that hindered the control strategy. Therefore, alternative strategies were necessary to minimize the antibiotic use and reduce the virulent strains occurrence. more...

Swollen Head Syndrome (SHS) is a disease of upper respiratory tract affecting broilers and broiler breeders which resulted in inflammatory exudates beneath the skin. SHS has been described as a multi-factorial disease where the initial lesion mainly caused by avian Metapneumo virus (aMPV), while the clinical signs are a consequence of bacterial complications and the severity of the disease depends on environmental factors. This study was planned to detect and try to isolate the etiological agents of SHS from 40 broiler flocks in 3 Egyptian Governorates (Sharkia, Dakahlia and Damietta). The chickens incorporated swollen heads and respiratory manifestations as nasal discharges, coughing, tracheal rales and frothy conjunctivitis from different localities. Samples included trachea and lung tissues, choanal cleft swabs and scraps from sinuses and turbinates. The AMPV subtype B was detected in 5 flocks by Real Time Polymerase Chain Reaction (RRT-PCR) -using 2 specific probes for differentiation of subtypes A and B. the AMPV-subtype B was detected with the percentage of 12.5%. Bacterial examination of collected samples revealed presence of mixed infection in some of examined flocks with isolation of E. coli in a percentage of 70%; Proteus mirabilis 40% and Pseudomonas aeruginosa (25%). In conclusion, to our knowledge, this is the first detection of aMPV among broiler chickens suffering from SHS in Egypt, using RRT-PCR in concurrent bacterial infections with E. coli, P. mirabilis and P. aeruginosa. more...

1. Avipoxvirus (APV) infections are one of many threats inflicting economic losses within the poultry industry, particularly in tropical and subtropical countries. A proper and comprehensive study for APVs is needed to increase the knowledge concerning the diversity and evolution of the virus. 2. For this purpose, 136 bird flocks of different species and breeding types were examined for APV infection between October 2016 and November 2017. One hundred and thirty samples had visible pocks on the chorioallantoic membrane (CAM) which were designated as fowl pox-like viruses via amplification of 578 bp from the P4b gene and 1800 bp from the fpv140 locus. 4. A comprehensive phylogenetic analysis of fpv167 locus (P4b), fpv140 locus (fpv139 and fpv140) and fpv94 (DNA polymerase) revealed that all the analysed strains belong to fowl pox-like viruses (clade A; subclade A1 and A2). Based on the fpv140 locus full nucleotide sequence, three turkey originated strains were seen to be divergent from chicken originated sequences and branched into novel subclade A1.b. 5. Trees comparison, within the term of speculation of virus-host specificity, clearly highlighted a high order specific subgrouping among subclades in the case of the fpv140 locus (including fpv139 and fpv140). Hence, the fowl poxvirus, turkey poxvirus and pigeon poxvirus strains clustered into distinct host-specific subclades A1a, A1.b and A2, respectively, which could not be seen in the FWPV-P4b and DNA polymerase phylogeny. more...

Chicken infectious anemia virus (CIAV) is among the naturally occurring viruses that cause immunosuppression in chickens. In the present study, the impact of CIAV infection on both NDV vaccination immune responses and bird performance were demonstrated. Post CIAV infection, the mean live body weights of the ND-vaccinated groups showed improvement compared with the non-NDV vaccinated groups. The immunosuppressive effects of CIAV infection was higher and more obvious on live ND vaccinated group compared with the other vaccinated groups. The vaccination with combination of live and inactivated vaccines showed better HI-NDV Ab responses especially when inactivated vaccine was administrated at 9 days (group II). In consistent, both the phagocytic Percent and Index were lower in case of vaccination with live NDV vaccine only and CIAV infection. Birds were vaccinated with both live and inactivated NDV vaccines at different time points showed superior protection rate (100%) compared with the other groups. Microscopically, CIAV infection led to severe deterioration in the lymphoid tissues (thymus, bursa, spleen and bone marrow) such as focal to diffuse depletion of lymphocytes and hematopoietic cells. This study highlights the negative impact of CIAV infection on both bird performance and immune status. more...

In a trial to investigate the bacterial causes of leg infection in broiler chickens, a total of 308 samples (foot bad and hock joint) of broiler chickens suffering from lameness were collected randomly from different broiler farms at Ismailia, Sharkia and North Sinai Governorates. Clinical and post-mortem examination, besides bacteriological analysis of the samples were carried out. The bacteriological investigation revealed the isolation of Staphylococcus aureus (83.8%, 258/308), Staphylococcus lentus (16.2%, 50/308), Escherichia coli (28.6%, 88/308); Salmonella spp. (1.3%, 4/308) , Pseudomonas aeruginosa (1.9%, 6/308) and Pasteurella multocida (1.9%, 6/308). Antimicrobial sensitivity tests of the isolated bacteria revealed that S. aureus isolates were sensitive to Cefotaxim, Ciprofloxacin, Enrofloxacin and sulpha Trimethoprim. Virulence associated factors (coagulase gene and clumping factor) were determined in S. aureus isolates by conventional PCR. The results showed that the coagulase gene was identified in 10 S. aureus isolates, while, the clumping factor was detected in only two isolates. It could be concluded that the staphylococcal infection is the most important cause of arthritis in broiler chickens. more...

During the period from 2015 to 2017, frequent outbreaks of inclusion body hepatitis (IBH) were observed in broiler chickens and falcons in Saudi Arabia. Fifty samples were collected from both species. The histopathological examination and polymerase chain reaction confirmed the IBH infection in eight samples (five samples from chickens and three samples from falcons). The genomic sequence and phylogenetic analysis based on nucleotide and amino acid sequences of Saudi strains, reference fowl aviadenoviruses (FAdVs) and field viruses available in Genbank revealed that all investigated FAdVs clustered into FAdV-2 (species D) and FAdV-6 (species E). The host-dependent characterization revealed that falcon origin strains showed low identity (∼35%) with falcon adenoviruses isolated from USA, which clustered into a separate group. The identification of FAdV-D and FAdV-E in diseased falcons and chickens indicates cross-species transmission although falcons and chickens are phylogenetically different. The control of IBH infection in falcons and chickens should be based on the separation of carriers and susceptible chickens as well as falcons to prevent cross-species contact. Vaccination is an important method for prevention of IBH. The characterization of newly emerging FAdV strains provides valuable information for the development of an efficacious control strategy based on the molecular structure of current circulating FAdV strains in different species of birds. more...

The present work aimed to isolate and characterize Salmonellae from chickens, ducks, quails and turkeys in five Egyptian Governorates. Polymerase chain reaction (PCR) was used for the detection of common virulence genes. A total of 265 flock samples (150 chickens, 60 ducks, 30 quails and 25 turkeys) were collected from Dakahlia, Kafrelsheik, Damietta, Sharkia and Gharbia Governorates. Birds were subjected to either clinical and/or post-mortem examination, in adittion to isolation and identification of salmonellae from internal organs including liver, lung, spleen, caecum and unabsorbed yolk sac. Biochmeical and serological identification of the isolates was done. Twenty eight birds (10.6%) were found positive for Salmonella isolation. The number and percentage of positive chickens, ducks, quails and turkeys were 16 (10.7%), 7 (11.7%), 3 (10%) and 2 (8%), respectively. Salmonella Typhimurium, S. Enteritidis, S. Kentucky, S. Paratyphi A, S. Molade, S. Heidelberg, S. Infantis and S. Apeyeme were isolated from chickens. While S. Enteritidis, S. Typhimurium, S. Paratyphi A, S. Kentucky, S. Inganda and S. Bargny were isolated from ducks. While, S. Virchow, S. Tamale and S. Typhimurium were isolated from Quails and S. Wingrove, finally, S. Kentucky were isolated from turkeys. Molecular characterization of common virulence genes Salmonella outer proteins (sopB), Plasmid encoded virulence gene (spvC), salmonella enterotoxin (stn) and bacterial colonization factor (bcfC) showed the presence of stn and bcfC genes in all isolates, while, sopB and Spv genes were present in 64.3% and 10.7%, respectively. It is concluded that salmonellae with common virulence genes were widely spread among domestic birds in Delta areas, Egypt, resulting in economic and public health problems which require the application of strictly biosecurity measures in poultry rearing. more...

The complete genome sequence of a virulent Newcastle disease virus (NDV) isolated from chickens in Egypt was determined and compared to the sequence of NDV strains isolated from different parts of the world. The genome is 15,186 nucleotides (nt) long and consists of 6 genes in the order of 3′-N-P-M-F-HN-L-5′. The genome contains a 55-nt leader region at the 3′ end and a 114-nt trailer region at the 5′ end. Interestingly, the phylogenetic analysis showed that strain Egypt is closely related with the NDV strains isolated in China. In addition, the sequence of the fusion protein cleavage site of strain Egypt was identical to that of the NDV strain recently isolated in Mali. Determination of complete genome sequences of additional NDV strains from Africa is necessary to understand the epidemiology of currently circulating viruses in Africa. more...