Apramycin resistance plasmids inEscherichia coli: possible transfer toSalmonella typhimuriumin calves

Abstract

SUMMARYAn outbreak of salmonellosis in calves was monitored for persistence of Salmonella typhimurium excretion in faeces and the effect of treatment with apramycin. Prior to treatment apramycin-resistant Escherichia coli were present but all S. typhimurium isolates were sensitive. Following the treatment of six calves with apramycin, apramycin-resistant S. typhimurium were isolated from two treated calves and one untreated calf. Plasmid profiles of E. coli and S. typhimurium were compared and plasmids conferring resistance to apramycin and several other antibiotics were transferred by conjugation in vitro from calf E. coli and S. typhimurium isolates to E. coli K-12 and from E. coli to S. typhimurium. The plasmids conjugated with high frequency in vitro from E. coli to S.

Human isolates of apramycin-resistant Escherichia coli which contain the genes for the AAC(3)IV enzyme

“…These were chosen because all the apramycin-resistant E. coli isolated by the authors fromn pigs and calves showied cross resistance to gentamicini [3].…”

“…uriumn of bovine origin is a common food poisoning pathogen in man. Hunter and co-workers [3] have subsequently described the presence of the same apramycin resistance plasmid in E. coli and S. typhinruriium in an outbreak of salmonellosis in calves. Transfer of the plasmid from E. coli to S. typhiniurrirun may have occurred during treatment of the calves with apramycin.…”

“…Attempts were made to transfer resistance from some isolates in broth matings using a method previously described [3].…”

Mechanisms of Resistance in Multiple-Antibiotic-Resistant Escherichia coli Strains of Human, Animal, and Food Origins

“…The AAC(3)-IV enzyme modifies apramycin in addition to GEN. Apramycin is used exclusively in veterinary medicine, but the GEN-related chemical structure and the mobility of the aac3-IV gene inside plasmids may have contributed to the selection and dissemination of these strains in a human environment (17).…”

Effects of HACCP system implementation on reproduction, milk quality, and milk sanitation on dairy farms in Korea

“…However, there is a growing concern over the extensive use of medication in the livestock industry. One concern is the opportunity for the development of antibiotic resistant pathogens and also the antibiotic residues left in animal products intended for human consumption (Chee-Sanford et al, 2001;Dowson et al, 1994;Hunter et al, 1992). The study revealed a significant reduction in monthly antibiotic expenses after implementing the HACCP system on dairy farms.…”