Antimicrobial Susceptibility of Campylobacter spp. Isolated from Cattle in Mongolia.

Poultry and cattle are the major reservoirs of Campylobacter infection in humans. However, no information is available on Campylobacter spp. in cattle in Mongolia. Thus, this study aimed to assess their prevalence and antimicrobial resistance. Between 2019 and 2023, rectal swabs were collected from cattle on dairy farms around Ulaanbaatar city and in total, 35 Campylobacter spp., including 23 C. jejuni, 7 C. hyointestinalis, 4 C. fetus, and 1 C. lari, were isolated. Multilocus sequence typing of C. jejuni cattle isolates revealed substantial genetic diversity and identified 7 sequence types (STs) including ST61, which is known to be associated with cattle and sheep. Interestingly, the antimicrobial resistance patterns of the C. jejuni cattle isolates completely differed from those of previously reported chicken isolates. Excluding one ciprofloxacin-resistant isolate, all isolates were susceptible to tetracycline and ciprofloxacin. This is the first report on the characterization of Campylobacter spp. in cattle in Mongolia. Although no official statistics of human campylobacteriosis are currently available in Mongolia, data on Campylobacter spp. in food-producing animals represent valuable information for investigating potential sources and infection routes to humans.