Development of a novel biochip for rapid multiplex detection of seven mastitis-causing pathogens in bovine milk samples.

To efficiently prevent and treat bovine mastitis and minimize its effect on the dairy industry, a sensitive, rapid, and specific test is required for identifying the mastitis-causing pathogens. In this study, a biochip capable of detecting 7 common species of mastitis-causing pathogens, including Corynebacterium bovis, Mycoplasma bovis, Staphylococcus aureus, and the Streptococcus spp. S. agalactiae, S. bovis, S. dysgalactiae, and S. uberis, within 6 hr was developed. The technique is based on DNA amplification of genes specific to the target pathogens and consists of 4 basic steps: DNA extraction of bacteria, polymerase chain reaction, DNA hybridization, and colorimetric reaction. To examine the accuracy and specificity of this biochip, a preliminary test with 82 random quarter milk samples were analyzed and compared with results from conventional microbiological methods conducted simultaneously. Results from all but 1 sample analyzed by the biochip were in agreement with those analyzed by bacteriology. The biochip could be a feasible tool for rapidly diagnosing mastitis-causing pathogens in milk and providing information for a more effective treatment to cure mastitis.