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Subcutaneous nodular onchocercosis was detected and investigated in 17 Japanese Sika deer (Cervus nippon), captured in Gifu and Shiga Prefectures/Japan, in the period between 2016 and 2017. The worms were found in all the seventeen deer within characteristics subcutaneous nodules dispersed mainly in the back (especially in the lumbar region and flanks), with few scattered nodules were located at the forelimbs and neck. The all collected nodules were examined stereo-microscopically. The parasites were extracted from the nodules and identified through morphological and histopathological examinations. Molecular identification through sequencing of the following genes; internal transcribed spacer subunit 2 (ITS2)–28S ribosomal RNA (28S rRNA), cytochrome c oxidase subunit 1 (cox1) and mitochondrially encoded NADH dehydrogenase subunit 2 (NAD2) were performed. The histopathological, molecular and phylogenetic analysis demonstrated that, the filarial nematode isolated from Gifu and Shiga Prefectures in Japan is O. flexuosa. This is the first report about presence of O. flexuosa in Japanese Sika deer (Cervus nippon) in Gifu and Shiga Prefectures. SUPPLEMENTARY INFORMATION: The online version supplementary material available at 10.1007/s12639-021-01453-3.

Newcastle disease virus (NDV), a major pathogen of poultry worldwide, causes significant economic losses in the poultry industry. To characterize the ability of recently isolated virulent strains of NDV genotypes VI and VII to cause disease in quails, and to evaluate the efficacy of two NDV vaccines against such strains, Japanese quails were experimentally inoculated with either NDV genotype VI (Pigeon F-VI strain) or VII 1.1 (GHB-328 strain) with or without vaccination with inactivated NDV vaccine of genotype II (La Sota strain) or VII (KBNP strain). Mild to severe neurological signs developed in quails inoculated with the Pigeon F-VI strain from 3 to 14 days post infection (PI) and from 4 to 10 days PI in birds infected with the GHB-328 strain. The mortality rates were 46% and 33% for birds inoculated with NDV VI and NDV VII 1.1, respectively. The severity of histopathological changes depended on the viral isolates used. Vaccination with the La Sota or KBNP vaccine strain successfully protected quails against NDV-induced mortality and decreased the severity of clinical signs, pathological changes and cloacal viral shedding. This study showed that these virulent NDV isolates had mild to moderate pathogenicity in quails and that both vaccines protected against challenge with both virus strains. NDV vaccine genotype VII improved the level of protection against challenge with the VII 1.1 genotype compared with the classic vaccine, but failed to protect quails against challenge with the VI genotype.

A group of hamsters (n = 25) was intranasally infected with equine herpesvirus-9 (EHV-9) and mRNA transcription levels of several proinflammatory (IFN-γ, TNF-α and IL-6) and anti-inflammatory (IL-4, IL-10 and TGF-β) cytokines were investigated in brain tissue using RT-qPCR. These levels were correlated with the severity of sequential histopathological changes and intensity of immunohistochemical labelling of virus antigen in brain. Early and progressive upregulation of all the proinflammatory and anti-inflammatory cytokines investigated (P 0.05) was correlated with increasing severity of encephalitis and viral antigen expression from 2 days post infection (dpi) with a peak at 4-5 dpi (P 0.05).

Egyptian farms is still attacked by several outbreaks of FMDV, a highly contagious viral disease that threatens the livestock industry worldwide. Many of these outbreaks are unreported. Hence, the epidemiological situation and molecular characterization of the currently responsible strains of recent FMD outbreaks are missed. To identify FMDV strains currently circulating in cattle herds and catch the recent update in the morphophonological changes due to that virus, we carried out this study on the FMD outbreak from 2016–2017 in Egypt. Clinical samples (post mortem tissues samples, oral swabs, epithelial suspensions from ruptured vesicles, and blood) were collected from clinically examined animals suspected to be of being FMD virus = 229 cattle and 138 buffalo. Of 175, 96 (54.8%) samples and 85 (44.3%) from 192 samples were positive in 2016 and 2017, respectively. Pathological examination revealed the classical lesions of FMDV as vesicular and erosive lesions on cornified epithelial tissues. Multi-focal areas of lympho-plasmocytic myocarditis were seen in the heart of all calves. Similar lesions were also observed in the heart of adult cattle that died in that outbreaks. Detailed pathological alterations in adult and young animals were described. Polymerase chain reaction (PCR) screening of tissue specimens using specific primers for FMDV was done. Serotype O was the only serotype that was detected in our study and submitted in the Genebank. The four field isolates of serotype O that have been submitted in the Genebank had been found to belong to the EA-3 topotype. Nucleotide sequencing of the VP1 region and phylogenetic analysis has been used to determine the relationships between our field isolates, other recently isolated Egyptian isolates, and other isolates from some African countries and vaccinal strain used for serotype O in Egypt. The presence of strains of increased virulence among cattle and buffalo in Egypt could be attributed to the introduction of new viral strains through uncontrolled transboundary movements of animals during the last public revolution in Egypt in 2011.

The prevalence of Gallibacterium anatis in poultry production has increased over the last two decades. However, only a few studies have explored the pathogenicity of this bacterium in commercial layer chickens. This trial studied the aspects of the pathogenicity of a Gallibacterium anatis biovar haemolytica local Egyptian isolate (previously registered as strain B14 with GenBank accession no. KJ026147). We used 500 base pairs of a 16S ribosomal RNA gene and the 16S-23S ribosomal RNA intergenic spacer, partial sequence in an experimental infection trial in commercial White Shaver layer chickens aged 19 wk. The hens were divided into three groups of 40 birds each. The hens in Groups 1 and 2 were experimentally infected through the intranasal (IN) and intravenous (IV) routes, respectively, with a dose of 0.2 ml/bird containing 1.2 × 109 colony-forming units/ml. In contrast, Group 3 was kept as a noninfected control group. Both IN and IV infections resulted in a delayed egg laying for 1 wk and a significant (P ≤ 0.05) drop in egg production by 7.81% and 10.28% compared with the control group over 7 wk. Severe lesions in the form of hemorrhagic pneumonia, catarrhal tracheitis, ovarian follicle and oviductal regression, and septicemia were evident on necropsy, demonstrating the pathogenicity of G. anatis as a primary pathogen.

This study aimed to investigate the neuropathogenesis of equine herpes virus 9 (EHV-9) by studying the effects of a single point mutation introduced in two different EHV-9 genes. The two EHV-9 mutants, 14R and 19R, were generated carrying a point mutation in two separate EHV-9 genes. These mutants, along with the wild-type EHV-9, were used to infect a hamster model. The EHV-9- and 19R-infected groups showed earlier and more severe clinical signs of infection than the 14R-infected group. The white blood cells (WBCs) count was significantly increased in both EHV-9- and 19R-infected groups compared to the 14R-infected group at the 4th day post infection (DPI). Viremia was also detected earlier in both EHV-9- and 19R-infected groups than 14R-infected group. There were differences in the anterograde transmission pattern of both EHV-9 and 19R compared to 14R inside the brain. Serum TNF-α, IL-6 and IFN-γ levels were significantly increased in both EHV-9- and 19R-infected groups compared to the 14R-infected group. Histopathological and immunohistochemical analyses revealed that the mean group scores for the entire brain were significantly higher in both EHV-9- and 19R- infected groups than 14R-infected group. Collectively, these results confirm that the gene product of Open Reading Frame 19 (ORF19) plays an important role in EHV-9 neuropathogenicity and that the mutation in ORF19 is responsible for the attenuation of EHV-9.

Summary The neuropathogenesis of equine herpesvirus 9 (EHV-9), a neurotropic herpesvirus, and its mutant clone (SP21) was studied experimentally in a hamster model. EHV-9-infected hamsters showed clinical signs of infection at 3 days post infection (dpi), while infection with SP21 resulted in clinical signs at 4 dpi. Clinical signs were more severe in the EHV-9-infected group than in the SP21-infected group. There was a significant difference in the time of anterograde transmission of EHV-9 and SP21 inside the brain. Viraemia was detected in the EHV-9-infected group at 4–5 dpi, while no viraemia was detected in the SP21-infected group. The serum concentration of tumour necrosis factor-α was significantly higher in EHV-9-infected animals than in those infected by SP21 group at 4–5 dpi, but there was no difference in the serum concentration of interferon-γ. The spatiotemporal profiles of viral replication and virus-associated histopathology were remarkably similar, were high in the olfactory bulb and cerebral hemispheres, and decreased progressively towards the medulla oblongata. The mean group scores of the histopathological changes for the entire brain were significantly higher in the EHV-9 group than in the SP21 group at all time points, starting from 3 dpi. These results suggest that the gene products of the open reading frame (ORF)19 and ORF14 play essential roles in the neuropathogenesis of EHV-9, as the two point-mutations detected in SP21 significantly altered the neuropathogenesis of the virus.

Encephalitis in hamsters, which was induced by equine herpesvirus (EHV)–9, EHV-1 strain Ab4p, and zebra-borne EHV-1, was investigated and compared to assess viral kinetics and identify the progression and severity of neuropathological findings. Hamsters were inoculated with EHV-9, EHV-1 strain Ab4p, and zebra-borne EHV-1 via the nasal route and euthanized at 24, 48, 72, 96, 120, 144, and 168 hours postinoculation (HPI). The inoculated hamsters had mild to severe neurological signs at 60 to 72, 96, and 120 HPI, and the mortality rate was 75%, 0%, and 0% for animals inoculated with EHV-9, EHV-1 strain Ab4p, and zebra-borne EHV-1 viruses, respectively. Inoculated hamsters had varying degrees of rhinitis and lymphoplasmacytic meningoencephalitis, as well as differences in the severity and distribution of cerebral lesions. Furthermore, the cellular distribution of viral antigen depended on the inoculated virus. Neuronal necrosis was widely detected in animals inoculated with EHV-9, while marked perivascular cuffs of infiltrating inflammatory cells and gliosis were detected in animals inoculated with EHV-1 strain Ab4p and zebra-borne EHV-1. In the present study, 3 viruses belonging to the herpesvirus family induced encephalitis after initial propagation in the nasal cavity. These viruses might travel to the brain via the olfactory pathway and/or trigeminal nerve, showing different distributions and severities of neuropathological changes.

In this study, we aimed to evaluate the preventive effects of Brazilian green propolis on equine herpes virus (EHV)-induced encephalitis in a hamster model. We first investigated the antiviral activity of Brazilian green propolis against EHV-9, and then, examined the effects of propolis on the kinetics and production of cytokines. Sixtyfive male, Syrian hamsters were divided into two treatment groups and control group. The 1st group is a control. The second group was infected intranasally with 50 μl of EHV-9 [3 × 104 plaque-forming units (pfu)] without propolis treatment. The third group received propolis at 500 mg/kg of ethanol extract of Brazilian green propolis by a gavage for 7 days, followed by intranasal inoculation with 50 μl of EHV-9 (3 × 104 pfu). Pre-treatment with propolis was not effective in preventing EHV-9-induced encephalitis via intranasal route. This speculation is supported by similar clinical signs and similar immunohistochemistry based on viral antigen distribution in the brain of infected hamsters in groups 2 and 3 from 3rd day post inoculation (dpi). There were significant increases in cerebral mRNA levels of IL-2, IL-10, and IFN-𝛾 after propolis administration in the propolis-treated group before and after EHV-9 challenge compared with the control non-treated group. In conclusion, Brazilian green propolis showed no obvious effect on the prevention of acute EHV-9-induced acute encephalitis in a hamster model, despite its immune-enhancing activity.

Avian oncogenic viruses include Marek’s disease virus (MDV), a highly contagious herpesvirus, as well as retroviruses such as avian leukosis virus (ALV) subgroups A to J and reticuloendotheliosis virus (REV). In this study, we are surveying the incidence of these viruses during 2011-2015. A total of 64 flocks were vaccinated against MDV by using bivalent vaccine (HVT FC-126 + Rispens CVI988) (45 commercial Brown, white layers and 19 broiler breeder flocks) suffering from increase mortality with high No. of culling birds, bad uniformity and the post mortem examination revealed the presence of tumor lesions in different visceral organs. The age of birds varied from 11-24week, located in eight different governorates; [El-Sharkia, El-Dakahlia, El-Behera, Ismailia, Damietta, El-Monofia, El-Giza, Alexandria] .The total mortality reached 32.6% in brown commercial layers, 25.2% in white commercial layers (with average 28.9%) , 35.7% and 25.2% in females and males of broiler breeders respectively. Samples were collected from a total number of 20 out of 64 examined flocks, the twenty flocks representive 8, 6 and 6 commercial brown, white layer and broiler breeders respectively from tumor organs (liver, spleen, kidney, Bursa of Fabricious, heart, nerve, brain, mesentery and proventriculus). The histopathology-positive tissue sections were identified and further con-firmed by RT-PCR in addition to a blood samples were also collected for serological test using ELISA for ALV and REV. PCR using primers specific to (MDV, ALV, REV) appeared to be the method of choice for rapid and accurate diagnosis of these viruses. PCR and ELISA tests demonstrated the presence of MDV only in all collected samples except one sample was positive for both MDV and REV virus but all samples were negative for ALV.