A Comparison of the Multi-class, Multi-residue Drug Analysis (MRD) and the Charm Kidney Inhibition Swab (KIS) Test Supporting Detection and Identification of Antimicrobial Drugs.

Project 11-225 - Researcher: Mark Mitchell

Project Start: 2012  Project Completion: 2013

The CFIA requires federal packing plants to randomly test carcasses for the presence of sulfamethiazine residues. Researchers at the University of Guelph Lab Services compared the current system of residue detection, called KIS (Kidney Inhibition Swab), with a new lab test called MRD (Multiresidue Drug test). Kidneys and diaphragms from 127 pigs were randomly selected from condemned carcasses from two federally-inspected Ontario abattoirs. Both organs were sampled for antibiotic residue with the KIS and MRD tests.  All tested kidneys came back negative for antimicrobial residue using the KIS test, however kidneys and diaphragms from 17 carcasses came back positive for residue using the MRD test.   While positive test results were found on the MRD test, only one sample was over the acceptable residue limit.  The most common residues found on the MRD test werelincomycin, chlotetracycline, and sulfamethazine,  which are allcommonly found in feed.

The results demonstrate that the KIS test is able to acuratly indicate the presence of antimicrobial residue if it is at the acceptable residue limit or greater but the MRD test can identify antimicrobial residue at low levels and can name the specific drug found and the amount present.   Why use one test over the other?  A KIS test can be done at the plant with the general “positive” or “negative” result being immediately determined.  The MRD test must be sent to a lab, is more time consuming, expensive and labour intensive and not suitable for use as a quick test in the plants.

Final Report to OP