Evaluation of four commercial test for detection of ceftiofur in waste milk tank samples

Abstract

Antimicrobial resistance is a great concern for human and animal health. Over the years increasing concern has been established over drug resistance to 3rd generation cephalosporins, including ceftiofur. Drug use in lactating animals commonly results in drug residues in the milk that in the U.S. is frequently used as a feed source for pre-weaned calves. This milk is commonly called waste milk, and also includes milk from cows with high somatic cell counts (SCC) and fresh cows. Feeding waste milk to preweaned calves has been shown to potentially result in a higher selection of cephalosporin resistant bacteria. The objective on this study was to evaluate factors affecting the specificity, specificity and predictive values of 4 commercially available tests (labeled for detecting beta-lactam drug residues in comingled milk) when testing waste milk (WM) tank samples.