Veterinary Research Forum

Abstract Infectious bronchitis, being caused by a coronavirus, is a significant disease affecting broiler and layer chickens, leading to substantial losses in the poultry industry due to the high mortality rates and decreased egg yield. Nearly 30 serotypes and 100 variants were described to date; developed vaccines are being for some severe cases, like the Massachusetts strain, to mitigate the effects. Determining the vaccinal strain's titer is crucial for creating an effective vaccine, and calculating the virus infectivity in the egg embryo is very important using dilutions ranging from 10^-3 to 10^-8, from each dilution 0.10 mL is used. The aim of this study was to determine the effects of the avian bronchitis virus injected into the allantoic cavity of ten days old embryonated eggs. Real-time polymerase chain reaction tests determined the viral load in the allantoic fluid. The embryos were removed to study gross injuries. The trachea, lung, and mesonephros were removed and submitted for histopathological studies, and nuclear factor-kappa B immunofluorescence analysis. The results revealed that the dilution of one-thousandth of the virus in the embryos caused the highest organ damage and viral replication. Varying degrees of hyperemia, edema, cellular infiltration, and degeneration were observed in the trachea, lung, and mesonephros depending on the virus dilution. This study provides valuable insights into the pathogenesis of the avian bronchitis virus, and has a potential impact on achieving an effective vaccine.

Abstract The angiogenesis process is a pivotal cellular process involved in both developmental and pathological circumstances. In this study we investigated effect of Urtica dioica agglutinin (UDA), as an unusual phyto-lectin from the chitin-binding protein family, on the angiogenesis of chicken embryos. The UDA was extracted from plant rhizomes and purified by affinity chromatography column. The activity of this lectin was assayed by hemagglutination test on the human RBCs. Anti-angiogenic effect of UDA on the extra-embryonic layer of the chick egg was studied in the different concentrations. Our results showed that the minimum concentration of UDA for agglutination were 48.00 and 15.00 µg mL^-1 in macro- and microscopic studies, respectively. Because the number and length of the vessels were dramatically decreased at 100 µg kg^-1 of UDA, the lectin had an inhibitory effect on angiogenesis of the embryonic vasculature of the chick. We concluded that UDA might target the vascularization events through binding to GlcNAc-conjugates. More investigations are needed to clarify the angiogenesis-related therapeutic roles of this interesting biomolecule.