... in both countries, and ceftiofur and apramycin use in Canada, and enrofloxacin use in Vietnam. Frequent usage of agents in the past, such as chloramphenicol in Vietnam and nitrofurantoin in ... disease) in 2007 and submitted to the NIVR in Vietnam or the FMV in Québec, Canada, were initially tested by PCR for the presence of defining genes of ETEC and STEC pathotypes. They were then virotyped ... tested by PCR for the presence of defining genes of ETEC and STEC pathotypes. They were then virotyped by colony hybridisation (Ngeleka et al., 2002) for detection of the presence of 20 virulence...