Occurrence of plasmids and antibiotic resistance among Campylobacter jejuni and Campylobacter coli isolated from healthy and diarrheic animals

Abstract

Serologically defined strains of Campylobacter jejuni and Campylobacter coli from healthy and diarrheic animals were examined for the occurrence of plasmid DNA in association with the antibiotic susceptibility of the bacterial host and the health status of the animal host. Of all campylobacter organisms surveyed, 53% (116 of 200) contained plasmid DNA. A plasmid occurrence rate of 73.8% was obtained for C. coli from healthy pigs, contrasted by lower plasmid occurrence rates for C. coli from diarrheic pigs (30%) and from all diarrheic animals (21.4%). For C. jejuni, in contrast, only 13.6% of healthy cattle contained plasmid DNA, contrasted by a higher plasmid occurrence rate of 31.2% from diarrheic cattle. A high plasmid occurrence rate of 75.8% was observed for C. jejuni from healthy chickens. Campylobacter plasmids ranged in size from '1 to 86 megadaltons. Antibiotic susceptibility for 52 animal isolates (excluding chickens) indicated that most isolates were susceptible to kanamycin, erythromycin, gentamicin, tetracycline, and compound sulfonamide, whereas few were susceptible to bacitracin (19.2%); approximately half were susceptible to ampicillin (55.8%) and streptomycin (51.9%), and no isolates were susceptible to penicillin G. More isolates containing plasmids were resistant to ampicillin, tetracycline, and gentamicin than were isolates not carrying plasmids, there being a statistically significant difference for tetracycline and gentamicin, which suggested that these two antibiotics were probably plasmid mediated. The antibiotic susceptibility patterns of 21 chicken isolates of C. jejuni, by contrast, were different in that most were susceptible to ampicillin in addition to kanamycin, erythromycin, and gentamicin, whereas few were susceptible to compound sulfonamide, streptomycin, and tetracycline in addition to penicillin G and bacitracin. A 30or 39-megadalton plasmid, or both, common to many of the chicken isolates was usually associated with tetracycline resistance. Campylobacter jejuni and to a lesser extent Campylobacter coli have been associated with both human and animal diseases, most commonly causing gastroenteritis (4, 5, 9, 17, 19, 25, 34). Campylobacter spp. now have been isolated from a wide range of hosts (34, 37, 42, 44), and it * Corresponding author. commonly are carried on plasmids, as are virulence properties such as attachment factors, toxin production, and invasiveness (11). Although C. jejuni and C. coli are known to carry plasmids (2, 7, 40, 41), no plasmid yet has been correlated to pathogenicity and only tetracycline resistance has been shown to be carried on a transferable 38megadalton (MDa) plasmid (40, 42). In this study, C. jejuni 339

Antimicrobial susceptibility patterns of thermophilic Campylobacter spp. from humans, pigs, cattle, and broilers in Denmark

“…However, only 7 (7%) of 95 isolates from broilers, 1 (3%) of 29 isolates from cattle, and 1 of the 3 isolates from pigs were resistant to erythromycin. This is in general agreement with the findings of previous studies among animals (5,6,24,27,29) and among humans in other countries (1,12,18,19,(22)(23)(24)29).…”

“…As also reported by Cabrita et al (6), only a few C. coli isolates were resistant to tetracycline; however, this is in contrast to observations by other authors (5,11,20,29). A high proportion (48%) of C. coli isolates from pigs were resistant to streptomycin, which is in agreement with previous studies (5, 6, 11), whereas only a few isolates from broilers (6%) and none from humans were resistant.…”

“…One of the three isolates from pigs also tested resistant to streptomycin. Relatively high levels of resistance to streptomycin among isolates from cattle have also been reported in other studies (5,6,27).…”

Resistance to antimicrobial agents used for animal therapy in pathogenic‐, zoonotic‐ and indicator bacteria isolated from different food animals in Denmark: a baseline study for the Danish Integrated Antimicrobial Resistance Monitoring Programme (DANMAP)

“…The gene encoding kanamycin resistance in campylobacter has been identified and found to encode simultaneous resistance to neomycin (107). In other studies most isolates have been found susceptible to kanamycin (11,14), even though some resistance has been detected among C. coli isolates from pigs (40).…”

Exploring PFGE for Detecting Large Plasmids in Campylobacter jejuni and Campylobacter coli Isolated from Various Retail Meats

“…Some strains of Campylobacter were also found to harbor kanamycin along with tetracycline resistance plasmids [ 14 ]. Similarly, Campylobacter was found to carry plasmids associated with resistances to gentamycin, penicillin G, and ampicillin [ 15 ]. Campylobacter species isolated from retail meats were found to be resistant to several antimicrobials like tetracycline, doxycycline, erythromycin, nalidixic acid, and ciprofloxacin [ 16 ].…”