Development of polymerase chain reaction-lateral flow dipstick assay for detection of Mycoplasma bovis in cattle.

Mycoplasma bovis (M. bovis) is capable of causing a range of diseases in cattle, encompassing calf pneumonia, arthritis, conjunctivitis, meningitis, and mastitis. It is widely recognized as one of the predominant pathogens posing a significant threat to the global cattle industry. Therefore, accurate and sensitive methods are urgently needed to detect M. bovis. This study aims to detect M. bovis by combining colloidal gold with biotin-labeled oligonucleotides to improve detection sensitivity and form a chromogenic detection probe based on signal amplification technology. Here, we developed a sensitive and specific polymerase chain reaction-lateral flow dipstick assay (PCR-LFD) strip for efficient nucleic acid detection of M. bovis. A pair of specific primers with 5' ends labeled with biotin and digoxigenin probes was designed for PCR experiments. Colloidal gold particles-labeled anti-digoxigenin IgG coated gold-labeled test strip was prepared, streptavidin was used as the detection probe, and nitrocellulose membrane coated goat anti-mouse IgG was used as the control line. Our results showed that the detection limit of the PCR-LFD was 89 fg/µL for the M. bovis DNA. The results from the test strip were highly consistent with those from real-time qPCR. This assay were highly specific for M. bovis, as there were no cross-reactions with other microorganisms tested and the detection sensitivity of the test was also relatively high (97.67%). The novel strips present a promising tool for the cost-effective and sensitive diagnosis of M. bovis.