Development of a PCR-based dot blot assay for the detection of fowl adenovirus

Group-I Fowl adenovirus (FAdV) is still widespread in China's chicken farms, leading to huge economic losses. The traditional PCR method, which can detect all serotypes at the same time, is not sensitive enough to obtain accurate results, especially in some samples containing only a low titer of virus, such as contaminated live vaccine. In order to solve this problem, this study developed a dot blot assay based on the above PCR method. A total of 6 probes targeting the conserved region of FAdV were designed and systematically optimized through sensitivity, accuracy, and stability analyses. Results showed that it is not only suitable for 12 serotypes, but also effectively improve the sensitivity, which increased more than 100 times in comparison with PCR assay. Moreover, this sensitivity was increased 100 times when detecting contaminated live vaccine samples, showing the great prospect of this method in daily monitoring.