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Background/Objective: Highly pathogenic avian influenza (HPAI) H5 subtype remains a significant menace to both the poultry industry and human public health. Biosecurity and mass vaccination of susceptible commercial poultry flocks are crucial to reduce the devastating economic loss and hinder the evolution of the virus. Methods: In this study, we developed a multivalent avian influenza virus (AIV) vaccine, including strains representing the HPAI 2.2.1.1., 2.2.1.2., and 2.3.4.4b clades circulating in Egypt and the Middle East. Specific pathogen-free (SPF) two-week-old chickens were vaccinated with a single vaccine shot and observed for four weeks post-vaccination before being challenged. The challenge experiment involved using one strain of HPAI H5N1 subtype clade 2.2.1.2 and two strains of HPAI H5N8 subtype clade 2.3.4.4b derived from chickens and ducks. To assess the vaccine's potency and efficacy, the pre-challenge humoral immune response and post-challenge survival and virus shedding were evaluated. Results: All the vaccinated birds exhibited 100% seroconversion 2 weeks post-vaccination (2 WPV). In addition, protective antibody titers against each diagnostic antigen, i.e., 7.8 ± 1.8 (H5N1, clade 2.2.1.2), 10.0 ± 0.0 (H5N1, clade 2.2.1.1), and 7.5 ± 0.9 (H5N8, clade 2.3.4.4b) were detected 3 WPV. The vaccination achieved complete protection (100%) against all challenge viruses with no disease symptoms. The vaccinated birds exhibited a statistically significant reduction in oropharyngeal virus shedding 2 days post-challenge (DPC). Conclusions: This study illustrated that a single application of a multivalent genetic-matching whole AIV vaccine under laboratory conditions elicits adequate protection against the HPAI challenge, representing 2.2.1.2 and 2.3.4.4b clades. The developed vaccine has the potential to be a vaccine of choice against a broad range of HPAI in commercial flocks raised under field conditions in endemic areas. [ABSTRACT FROM AUTHOR]

Copyright of Assiut Veterinary Medical Journal is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Avian colibacillosis is one of the most devastating diseases in chickens, resulting in high economic losses as well as high morbidity and mortality. Colistin is considered one of the most effective antimicrobials against colibacillosis. The recent discovery of mobile colistin resistance (mcr-1) determinants in humans and animals raised serious concerns about its potential dissemination among bacteria. This study aimed to investigate the presence of mcr-1 gene among E. coli isolates in broiler chickens infected with colibacillosis. As an experimental design was performed on broiler chickens after molecular detection of mcr-1 gene to explore the efficacy of neomycin as a hydrophobic antibiotic wither in the mcr-1 absence or its existence after oral inoculation of E. coli strains. Results revealed the high prevalence of colibacillosis among broiler farms in addition to highly spread of colistin resistance among E. coli isolates either through isolation on specific colistin resistance medium or molecular detection of the mcr-1 gene. On other hand, by histological examination we observed that the presence of the mcr-1 gene among E. coli isolates improved the treatment efficacy of the hydrophobic antibiotic. As a result of the significant antibiotic resistance issues and high risk of transmission of antibiotic-resistant bacteria and genes to humans, the development of antibacterials only for animal uses without cross-resistance to existing antibiotics might afford a solution in the future. Although there is an increase in acquired antibiotic resistance genes, it is possible to take advantage of this phenomenon, which in turn led to an increase in the sensitivity of some other antibiotics. Therefore, we recommend studying pharmacokinetic of antibacterials and making the most of this widespread phenomenon. [ABSTRACT FROM AUTHOR]

Copyright of Assiut Veterinary Medical Journal is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A variety of illnesses, including arthritis, tenosynovitis, stunted growth, and malabsorption syndrome, are caused by Avian Reoviruses (ARVs), which have become more prevalent in Egypt during recent years and resulted in significant economic losses. This study investigated 27 suspected samples collected from 14 broiler breeders and 13 broilers suffering from immunosuppression, decreased body weight, and diarrhea. Fourteen samples tested positive based on RT-PCR, and the virus could be isolated from ten samples in Specific Pathogen Free (SPF) embryonated chicken eggs. Ten isolates were subjected to molecular and genetic analysis of the S1 gene (sigma C) and S2 gene (sigma A). The amino acid identity of the S1 gene revealed that these viruses are closely related to the viruses that were identified in Israel during 2020 (91.8%-97.2% identity) and belonged to the genetic cluster 5 (genotype 5), which also includes some viruses that are circulating in the United States and Canada. They also showed weak similarity (48.9%-50.2%) with the available vaccine strains in the Egyptian field that belong to cluster 1, genotype 1. The S2 gene showed amino acid homology of 91.7%-98.2% with the current vaccine used in Egypt. However, the Egy-Reo-7-2021 virus had the lowest similarity (84.2%-87.6%) to the available vaccine. It is hypothesized that the difference between field and vaccine strains may have contributed to the failure of current vaccinations to produce protective immunity against current ARV strains circulated in Egypt, which made the disease a problem to the poultry industry. Developing homologous vaccines and evaluating their potency and efficacy are required in Egypt. [ABSTRACT FROM AUTHOR]

Management of temporomandibular disorder (TMD) still attains researchers’ interest. Recently, platelets rich plasma (PRP) products especially plasma rich in growth factors (PRGF), has gained the focus of researchers in musculoskeletal field for being safe autologous substance with promising outcomes. PRGF is a serum that devoid the white blood cells, RBCs, however, the platelets were concentrated by 2.84-fold. The regenerative effect of the PRGF and its known therapeutic rule on injured tissues renders it research worthy topic. At this article we will review the rationale of PRGF intra-articular injection in TMD patients. [ABSTRACT FROM AUTHOR]

Background: Lipocalin-2 (LCN2) is an adipokine related to insulin resistance and metabolic syndrome (MetS) in addition to its role in innate immunity and apoptosis. Objective: To estimate LCN2 tissue levels (lesional and non-lesional) in psoriasis. To assess the metabolic status of patients and to detect any possible associations between LCN2 and MetS. To evaluate the effect of narrow-band ultraviolet B (NBUVB) on tissue LCN2 in psoriasis. Methods: This case-control study was conducted on 25 psoriatic patients and 25 healthy controls. Dyslipidemia and MetS have been evaluated. Tissue LCN2 was estimated using ELISA technique before and after treatment with NBUVB. Results: Tissue LCN2 was significantly higher in psoriasis, with no significant difference as regards dyslipidemia or metabolic disturbance in these patients. Both lesional and non-lesional LCN2 and PASI score dropped significantly after NBUVB. No significant correlations have been detected between tissue LCN2 and disease extent or PASI score. Significant positive correlations were detected regarding tissue LCN2 levels between lesional and non-lesional samples before and after treatment. Conclusions: Psoriatic patients were at higher risk of metabolic disorders. LCN2 was not related to metabolic disturbances in our patients. NBUVB might exert its therapeutic effect in psoriasis through reduction of tissue LCN2. [ABSTRACT FROM AUTHOR]

Ten infectious bursal disease virus (IBDV) field strains were isolated from 15 broiler flocks located in various parts of Asyut, Egypt. Seven strains were subjected to comparative sequencing and phylogenetic analyses to help provide optimal control program for protection against IBDV infection. Sequence analysis of a 530 bp hypervariable region in the VP2 gene revealed that the rate of identity and homology was around 95.6-99.1%. Sequence characterization revealed the 7 strains identified as vvIBDV with the four amino acids residues typical of vvIBDV (2421,2561,2941,299S). The BURSA-VAC vaccine was the nearest vaccine in sequence similarity to the local examined IBDV strains followed by CEVACIBDL then Bursine plus and Nobilis Gumboro indicating its probable success in the face of incoming outbreaks when using these vaccines. Phylogenetic analysis revealed that the presence of three clusters for the examined strains and are grouped with reference very virulent IBDVs of European and Asian origin (Japanese and Hong Kong) strains suggesting the different ancestors of our isolates. The antigenic index showed a number of changes on the major and minor hydrophilic antigenic peaks of the virus surface structures indicating a new genetic evolution of the surface structure epitopes that may lead to vaccination failure and reemergence of the disease. [ABSTRACT FROM AUTHOR]