Monitoring of antibiotic resistance in bacteria isolated from laboratory animals.
The drug resistance of microorganisms isolated from laboratory animals never treated with antibiotics is being reported consistently, while the number of laboratory animals used in medicine, pharmacy, veterinary medicine, agriculture, nutrition, and environmental and health science has increased rapidly in Korea. Therefore, this study examined the development of antimicrobial resistance in bacteria isolated from laboratory animals bred in Korea. A total of 443 isolates (7 species) containing 5 Sphingomonas paucimobilis, 206 Escherichia coli, 60 Staphylococcus aureus, 15 Staphylococcus epidermidis, 77 Enterococcus faecalis, 27 Citrobacter freundii, 35 Acinetobacter baumannii were collected from the nose, intestine, bronchus and reproductive organs of ICR mice and SD rats. Of these species, Acinetobacter baumannii and Enterococcus faecalis showed significant antimicrobial resistance according to the minimum inhibition concentration (MIC) in E-test. In case of Acinetobacter baumannii, several isolates showed MIC values 16-128 µg/mL for cefazolin and cefoxitin, and higher resistance (128-512 µg/mL) to nitrofurantoin than that of standard type. Resistance to cefazolin, cefoxitin and nitrofurantoin was detected in 17.14, 20.00, and 8.57% of the Acinetobacter baumannii isolates, respectively. In addition, 44.1% of the Enterococcus faecalis isolates collected from the laboratory animals were resistant to oxacillin concentration of 16-32 µg/mL range, while MIC value of standard type was below oxacillin concentration of 6 µg/mL. These results suggest that in rodent species of laboratory animals, Acinetobacter baumannii are resistance to cefazolin, cefoxitin and nitrofurantoin, whereas those of Enterococcus faecalis were resistance to oxacillin.
Department of Biomaterials Science, Collage of Natural Resources & Life Science, Pusan National University, Miryang, Korea.
Jun-Seo
JS
Goo
Mee-Kyung
MK
Jang
Sun-Bo
SB
Shim
Seung-Wan
SW
Jee
Su-Hae
SH
Lee
Chang-Jun
CJ
Bae
Songhee
S
Park
Kwang-Je
KJ
Kim
Ji-Eun
JE
Kim
In-Sik
IS
Hwang
Hye-Ryun
HR
Lee
Sun-Il
SI
Choi
Young-Ju
YJ
Lee
Chul-Joo
CJ
Lim
Dae-Youn
DY
Hwang