Development of colloidal gold-based test strip for rapid detection of serotype 4 fowl adenovirus.

The outbreaks of hepatitis-hydropericardium syndrome (HPS) caused by serotype 4 fowl adenovirus (FAdV-4) have spread from broilers to laying hens, breeders, geese and Cherry Valley duck, resulting in high economic losses to the poultry industry globally. In this study, a rapid colloidal gold test strip for detection of FAdV-4 was developed by using two monoclonal antibodies (mAbs) against the Fiber-2 of FAdV-4. Specificity analysis revealed that the test strip only reacted with FAdV-4, but not with other pathogens including different serotypes of fowl adenovirus and other avian pathogens tested. The limit of the detection (LOD) of the strip could reach as low as 0.1 μg/0.1 mL of GST-Fiber-2 protein and 1 × 105 TCID50/0.1 mL of FAdV-4, respectively. Moreover, the test strip could be efficiently applied in detecting tissue samples from diseased chickens with HPS. Comparison analysis further revealed that the test strip showed good compatibility with PCR assay for detection of virus isolates and clinical samples. In conclusion, our test strip provides an efficient on-site diagnostic method in a quick and convenient manner for detection of FAdV-4, especially in resource-limited areas.