Simultaneous Detection of Six Different Groups of Antimicrobial Drugs in Porcine Oral Fluids Using A Biochip Array-Based Immunoassay

Abstract

The objectives of this study were 1) to determine whether a biochip array-based immunoassay could be used to detect 6 different group antimicrobials in porcine oral fluids collected under experimental conditions; 2) to determine the feasibility of antimicrobial detection in clean versus dirty oral fluid samples; and 3) to determine if the assay could be used to detect chlortetracycline in oral fluids of swine ingesting a routine diet containing chlortetracycline. Biochip array-based immunoassay is currently used for simultaneous detection and quantitation of different group six antimicrobials in milk, urine, meat, honey, and feed. The assay had not been investigated for potential use in oral fluids. Following evaluation of different extraction procedures, a centrifugation method was chosen. Results showed that of the six target drugs, norfloxacin, ceftiofur, florfenicol, streptomycin, tylosin and tetracycline could be detected in both clean and dirty oral fluid samples. However, tetracycline was not well recovered in dirty samples. Chlortetracycline from tetracycline group was detected in all oral fluid samples collected from the field at concentrations ranging from 176.0-698.6 ppb. In conclusion, this assay can detect all target antibacterials from different groups in clean and dirty oral fluid samples with the exception of tetracycline which was not well-recovered from in dirty samples.