Development of a multiplexed Luminex assay for simultaneous detection of enteric viruses in cattle.

Viral and bacterial gastroenteritis and diarrhea have long been a problem in livestock with devastating effects on animal health and production causing a heavy financial burden on producers. Therefore, the bead-based multiplex detection assay was created for simultaneous detection of three livestock viral diarrheic agents viz. bovine rotavirus (BRV), bovine coronavirus (BCoV) and bluetongue virus (BTV). The primers and probes for triplex MAGPIX assay for simultaneous detection of three enteric viruses were designed and the assay was optimized for hybridization temperature, primer-probe and bead concentrations. The newly developed MAGPIX assay was used to determine the prevalence of these diarrhea-associated viruses by testing 200 fecal samples collected from Haryana state of India during 2018-2019. The limit of detection of the developed triplex assay was 1 × 10⁵, 1 × 10⁴, and 1 × 10⁵ RNA copies for BRV, BCoV, and BTV, respectively, being lower than the reverse transcription-quantitative polymerase chain reaction (RT-qPCR). However, it was higher than the conventional RT-PCR, showing it to be more sensitive. The newly developed MAGPIX assay was a rapid, cost-effective and high throughput diagnostic tool for identification of three major entero-pathogenic diarrhea associated viruses, either alone or in tandem, with the aim to prevent and control viral diarrhea in animals.