Naturally Occurring Frameshift Mutations in the tvb Receptor Gene Are Responsible for Decreased Susceptibility of Chicken to Infection with Avian Leukosis Virus Subgroups B, D, and E

Rapid and sensitive visual detection of avian leukosis virus by reverse transcription loop-mediated isothermal amplification combined with a lateral flow immunochromatographic strip assay

Considering that avian leukosis virus (ALV) infection has inflicted massive economic losses on the poultry breeding industry in most countries, its early diagnosis remains an important measure for timely treatment and control of the disease, for which a rapid and sensitive point-of-care test is required. We established a user-friendly, economical, and rapid visualization method for ALV amplification products based on reverse transcription loop-mediated isothermal amplification (RT-LAMP) combined with an immunochromatographic strip in a lateral flow device (LFD). Using the ALVp27 gene as the target, five RT-LAMP primers and one fluorescein-isothiocyanate-labeled probe were designed. After 60 min of RT-LAMP amplification at 64 °C, the products could be visualized directly using the LFD. The detection limit of this assay for ALV detection was 102 RNA copies/μL, and the sensitivity was 100 times that of reverse transcription polymerase chain reaction (RT-PCR), showing high specificity and sensitivity. To verify the clinical practicality of this assay for detecting ALV, the gold standard RT-PCR method was used for comparison, and consistent results were obtained with both assays. Thus, the assay described here can be used for rapid detection of ALV in resource-limited environments.

Advances on genetic and genomic studies of ALV resistance

Avian leukosis (AL) is a general term for a variety of neoplastic diseases in avian caused by avian leukosis virus (ALV). No vaccine or drug is currently available for the disease. Therefore, the disease can result in severe economic losses in poultry flocks. Increasing the resistance of poultry to ALV may be one effective strategy. In this review, we provide an overview of the roles of genes associated with ALV infection in the poultry genome, including endogenous retroviruses, virus receptors, interferon-stimulated genes, and other immune-related genes. Furthermore, some methods and techniques that can improve ALV resistance in poultry are discussed. The objectives are willing to provide some valuable references for disease resistance breeding in poultry.

Avian Leucosis Virus-Host Interaction: The Involvement of Host Factors in Viral Replication

Avian leukosis virus (ALV) causes various diseases associated with tumor formation and decreased fertility. Moreover, ALV induces severe immunosuppression, increasing susceptibility to other microbial infections and the risk of failure in subsequent vaccination against other diseases. There is growing evidence showing the interaction between ALV and the host. In this review, we will survey the present knowledge of the involvement of host factors in the important molecular events during ALV infection and discuss the futuristic perspectives from this angle.

Conservation of chicken male germline by orthotopic transplantation of primordial germ cells from genetically distant donors†

Successful derivation and cultivation of primordial germ cells (PGCs) opened the way to efficient transgenesis and genome editing in the chicken. Furthermore, implantation of male PGCs from non-chicken galliform species into the chicken embryos resulted in cross-species germline chimeras and viable offspring. We have recently improved the PGC technology by demonstrating that chicken male PGCs transplanted into the testes of adult cockerel recipients mature into functional sperms. However, the availability of this orthotopic transplantation for cross-species transfer remains to be explored. Here we tested the capacity of genetically distant male PGCs to mature in the microenvironment of adult testes. We derived PGCs from the Chinese black-bone Silkie and transplanted them into infertile White Leghorn cockerels. Within 15-18 weeks after transplantation, we observed restoration of spermatogenesis in recipient cockerels and production of healthy progeny derived from the transplanted PGCs. Our findings also indicate the possibility of cross-species orthotopic transplantation of PGCs. Thus, our results might contribute to the preservation of endangered avian species and maintaining the genetic variability of the domestic chicken.