Quantifying tetracycline resistance

This study’s goal was to evaluate the impact of sub-therapeutic feeding of chlortetracycline (CTC) on the fecal concentration of tet(C), a gene that confers tetracycline resistance via an efflux mechanism. We developed a real-time quantitative PCR assay to measure the quantity of tet(C) in whole fecal DNA samples. The vast proportion of variability in tet(C) (91%) was associated with differences in concentration between the individual pigs, and there was no significant difference in the copy number of tet(C)/mg of feces between the treatment and control pigs (p\u3e0.05, linear regression, SPSS 11.0.5)