Page Banner

United States Department of Agriculture

Agricultural Research Service

Research Project: EPIDEMIOLOGY, ECOLOGY, AND MOLECULAR GENETICS OF ANTIMICROBIAL RESISTANCE IN PATHOGENIC AND COMMENSAL BACTERIA FROM FOOD ANIMALS Title: Prevalence, species distribution and antimicrobial resistance of enterococci isolated from dogs and cats in the United States

Authors
item Jackson, Charlene
item Cray, Paula
item Davis, Johnnie
item Barrett, John
item Frye, Jonathan

Submitted to: Journal of Applied Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 24, 2009
Publication Date: October 1, 2009
Citation: Jackson, C.R., Cray, P.J., Davis, J.A., Barrett, J.B., Frye, J.G. 2009. Prevalence, species distribution and antimicrobial resistance of enterococci isolated from dogs and cats in the United States. Journal of Applied Microbiology. 107(4):1269-1278.

Interpretive Summary: The contribution of dogs and cats as reservoirs of antimicrobial resistant enterococci remains largely undefined. This is increasingly important considering the possibility of transfer of bacteria from companion animals to the human host. In this study, dogs and cats from veterinary clinics were screened for the presence of enterococci. A total of 420 enterococci were isolated from nasal, teeth, rectal, belly and hindquarter sites of 155 dogs and 121 cats. Eighty percent of dogs and 60% of cats were positive for enterococci. The majority of positive samples were from the rectal, hindquarter, and belly areas. Ten enterococcal species were identified; the predominant species identified was Enterococcus faecalis from dogs and E. hirae from cats. More isolates were resistant to ciprofloxacin in E. faecium, chloramphenicol resistance in E. faecalis and gentamicin resistance in E. faecalis from dogs. The majority of E. faecium from cats were resistant to nitrofurantoin. Multi-drug resistance (MDR) (resistance is greater than or equal to 2 antimicrobials) was observed to as few as two and as many as eight antimicrobials. Results from this study indicate that healthy dogs and cats are a source of antimicrobial resistant enterococci and may act as a reservoir of antimicrobial resistance genes that can be transferred to the human host. This research will be useful to policy makers and researchers studying the role that companion animals have in the dissemination and persistence of antimicrobial resistance in humans which may impact human health.

Technical Abstract: The contribution of dogs and cats as reservoirs of antimicrobial resistant enterococci remains largely undefined. This is increasingly important considering the possibility of transfer of bacteria from companion animals to the human host. In this study, dogs and cats from veterinary clinics were screened for the presence of enterococci. A total of 420 enterococci were isolated from nasal, teeth, rectal, belly and hindquarters sites of 155 dogs and 121 cats. Eighty percent (124/155) of dogs and 60% (72/121) of cats were positive for enterococci. From the total number of dog samples (n=275), 32% (n=87) of hindquarter, 31% (n=86) of rectal, and 29% (n=79) of belly samples were positive for enterococci. The majority of isolates originated from rectal samples (53/145; 37%) from cats. The predominant species identified was Enterococcus faecalis (105/155; 68%) from dogs and E. hirae (63/121; 52%) from cats. Significantly more E. faecalis were isolated from rectal samples than any other enterococcal species (P<0.05) for both dogs and cats suggesting site specific colonization of enterococcal species. The highest levels of resistance was to ciprofloxacin in E. faecium (9/10; 90%), chloramphenicol resistance in E. faecalis (17/20; 85%) and gentamicin resistance in E. faecalis (19/24; 79%) from dog samples and nitrofurantoin resistance in E. faecium (15/19; 79%) from cats. Multi-drug resistance (MDR) (resistance is greater than or equal to 2 antimicrobials) was observed to as few as two and as many as eight antimicrobials regardless of class. This study demonstrated that dogs and cats are a common source of antimicrobial resistant enterococci which may impact human health.

Last Modified: 11/24/2014