Avian leukosis retroviruses (ALV) cause lymphomas and other cancers in chickens. Previous studies have used enzyme-linked immunosorbent assays (ELISA) and indirect immunofluorescence assays (IFA) to detect ALV p27 group-specific antigens (GSA) in commercial chicken eggs. In the poultry industry eradication programme against exogenous ALV, ELISA assays are used to identify chickens infected with...

PIWI-interacting RNAs (piRNAs) protect the germ line by targeting transposable elements (TEs) through the base-pair complementarity. We do not know how piRNAs co-evolve with TEs in chickens. Here we reported that all active TEs in the chicken germ line are targeted by piRNAs, and as TEs lose their activity, the corresponding piRNAs erode away. We observed de novo piRNA birth as host responds to...

The subgroup J of avian leukosis virus causes myelocytomas, a neoplastic condition the birds that affects several visceral organs. In present study, myelocytomas were diagnosed in adult laying based on cytological and histopathological examination. On necropsy examination, showed enlarged liver spleen with multifocal tumorous growths liver, spleen, kidneys, lungs, ovary, proventriculus, intesti...

rence of avian leukosis virus subgroup J in commercial layer fl ocks in China. Z. Emerging of avian leukosis virus subgroup J in a fl ock of Chinese local breed [in Chinese].opment and application of polymerase chain reaction (PCR) tests for the detection of subgroup J avian leukosis virus. (exogenous avian leukosis virus, subgroup J) has an env gene related to those of en-dogenous elements EAV...

To the Editor: In recent years, cases of avian leukosis virus subgroup J (ALV-J) infection and tumors in commercial layer chickens and breeders of egg-type chickens have been emerging in the People’s Republic of China. ALV-J was fi rst isolated from meattype chickens with myeloid leukosis in 1988. Although egg-type chickens have been experimentally infected with ALV-J to induce tumors (1), fi e...

In order to ensure the safety of vaccines produced on avian cells, rigorous testing for the absence of avian retroviruses must be performed. Current methods used to detect avian retroviruses often exhibit a high invalid-test/false-positive rate, rely on hard-to-secure reagents, and/or have readouts that are difficult to standardize. Herein, we describe the development and validation of two cons...

The genome of nearly all chickens contains various DNA proviral insertions of retroviruses of subgroup E avian leukosis virus (ALVE). However, the elimination or control of ALVE gene expression is desirable to improve productivity, to improve resistance to avian leukosis virus (ALV)-induced tumours, and to develop safer live virus vaccines in chick embryos and cultured chick cells. Restriction ...

The identification of endogenous avian leukosis virus (ALV) and endogenous avian retrovirus (EAV) in chick cell-derived measles and mumps vaccines in current use has raised concern about transmission of these retroviruses to vaccine recipients. We used serologic and molecular methods to analyze specimens from 206 recipients of measles, mumps, and rubella (MMR) vaccine for evidence of infection ...

A genomic DNA library was constructed, in a bacteriophage 2 vector, from line 0 chick embryo fibroblasts (CEFs) infected with HPRS-103, an exogenous avian leukosis virus (ALV; envelope subgroup J) recently isolated from meat-type chickens, The library was screened at high stringency using a full length RAV-1 (subgroup A) proviral probe. From 106 plaques, two clones which hybridized strongly to ...