Feasibility of a DNA biosensor assay based on loop-mediated isothermal amplification combined with a lateral flow dipstick assay for the visual detection of eggs in faecal samples.

is an important nematode that causes ascaridiasis in free-range and indoor system chicken farms. Infection with may damage the intestinal mucosa and inhibit nutrient absorption, leading to a reduced growth rate, weight loss and a decreased egg production. Consequently, infection is a significant health problem in chickens. In this study, we developed a loop-mediated isothermal amplification coupled with a lateral flow dipstick (LAMP-LFD) assay for the visual detection of eggs in faecal samples. The LAMP-LFD assay consists of six primers and one DNA probe that recognize the internal transcribed spacer 2 (ITS2) region; it can be performed within 70 min and the results can be interpreted with the naked eye. Using the LAMP-LFD assay developed in this study, DNA was specifically amplified without any cross-reactions with other related parasites (, , , , sp., ) and definitive hosts (, ). The minimum detectable DNA concentration was 5 pg/μl, and the detectable egg count was 50 eggs per reaction. The assay can be performed in a water bath, without the need for morphological investigations and laboratory instruments. It is therefore a viable alternative for the detection of in chicken faeces and can replace classical methods in field screening for epidemiological investigations, veterinary health and poultry farming management.This is the first study using the LAMP-LFD assay for detection.The results can be observed by the naked eye.The developed assay can be used to detect eggs in faecal samples.