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Objective: Infectious laryngotracheitis virus (ILTV) is responsible for causing infectious laryngotracheitis (ILT), which is a rapidly spreading and extremely transmissible disease in chickens. The current research aims to isolate and characterize ILTV from layer chickens in Bangladesh. Materials and Methods: A total of 345 samples (trachea, larynx, and lungs) were collected from ILT-suspected dead and sick layer chickens of 32 ILT-suspected farms in three different outbreak districts (Gazipur, Tangail, and Mymensingh) of Bangladesh during the outbreak year 2021-2022. Rapid detection kits examined the samples for avian influenza virus (AIV) and Newcastle disease virus (NDV). ILTV-specific primers were used to screen 72 NDV- and AIV-negative samples by polymerase chain reaction (PCR). Using chorioallantoic membrane (CAM), the study isolated the ILT virus from 9 to 10-day-old seronegative embryonated chicken eggs (ECEs) using selected PCRpositive samples. The virus was confirmed using nucleotide sequencing, agar gel immunodiffusion test (AGIDT), viral neutralization test (VNT), and pathogenicity evaluations using mortality index for chicken embryos (MICEs) and intra-tracheal pathogenicity index (ITPI). Results: The results indicated that among the PCR-positive 10 samples, only two (Alim_ILT_1001 and Alim_ILT_1,000) were found positive using ECEs. There were two field isolates of ILTVs, as shown by the amplicon size of the ICP4 gene-based PCR. A phylogenetic study of the ICP4 gene revealed that the recent isolates have a close similarity with the ILTV isolates of Turkey, Bangladesh, and Australia. AGIDT revealed strong precipitation lines due to ILTV-specific antibodies reacting with field viruses, while VNT neutralized both isolates with conventional ILTV antibodies. The pathogenicity testing indicated that Alim_ILT_1001 had MICE and ITPI values of 0.77 and 0.63, whereas Alim_ILT_1,000 had 0.71 and 0.57. Conclusion: Both the ILTV isolates have similarities with the isolates of Turkey, Bangladesh, and Australia, and they are highly virulent for chickens. [ABSTRACT FROM AUTHOR]

Objective: The research aimed to isolate, adapt to cell culture, and characterize the lumpy skin disease virus (LSDV) from clinically infected cattle in Bangladesh. Materials and Methods: From September 2019 to June 2020, 37 skin nodules and skin swabs were aseptically collected from afflicted cattle in the outbreak regions of Jhenaidah and Kishoreganj in Bangladesh. The LSDV was isolated from embryonated specific pathogen-free (SPF) chicken eggs along the chorioallantoic membrane (CAM) route and the Vero cell line after several blind passages. The viral attachment protein was targeted for molecular detection using polymerase chain reactions (PCR). For phylogenetic analysis, PCR-positive products were partially sequenced. Results: The virus was evident in the cell line, showed cytopathic effects after the 13 blind passage, and on the CAM of SPF chicken eggs, exhibited thickening of the CAM with pock-like lesions. A total of 12 samples (32.43%) tested positive for LSDV by PCR. Phylogenetic analysis of the present isolates (accession numbers MN792649 and MN792650) revealed 100% similarity with strains from India (MN295064), Kenya (AF325528, MN072619, KX683219), Greece (KY829023), Serbia (KY702007), and Kazakhstan (MN642592); moreover, 99.43% to 100% similarity to the sheep pox virus. Conclusion: Partially sequenced LSDV was developed as a vaccine seed and was first isolated in Bangladesh and characterized at the molecular level. [ABSTRACT FROM AUTHOR]

Objective: Duck virus enteritis is a severe viral disease that kills ducks and swans worldwide. The clinical manifestations, gross pathology, molecular detection, and characterization of the duck virus enteritis virus (DVEV) in Australian black swans at a safari park in Bangladesh were described in this case report. Materials and Methods: On a safari park in Bangladesh, an Australian black swan flock exhibited clinical signs of anorexia, greenish watery diarrhea, increased thirst, partial paralysis, and death. Postmortem examinations of deceased swans revealed extensive pathological abnormalities in the trachea, liver, and spleen. To isolate DVEV, a viral inoculum produced from the liver and spleen of dead swans was implanted into 9-13-day-old embryonated duck eggs via the chorioallantoic membrane (CAM) route. DVEV was confirmed using a polymerase chain reaction (PCR) assay. Phylogenetic analysis was used to determine the genetic relationship between the DVEV isolates from Australian black swans, and 16 DVEV isolates previously described in the GenBank. Results: Hemorrhage was noted in the annular ring of the trachea, as well as an enlarged and hemorrhagic liver and spleen. The PCR assay amplified a 446-bp fragment of the DVEV DNA polymerase gene in the liver, spleen, and CAM homogenates. The phylogenetic analysis found that the DVEV isolates from swans were comparable to those from Bangladesh, India, Vietnam, China, Germany, the USA, and Egypt. Conclusion: According to the findings of this study, the DVEV was the cause of illness and mortality in an Australian black swan flock. [ABSTRACT FROM AUTHOR]