Tehran University of Medical Sciences Iranian Journal of Parasitology 1735-7020 14 2 2019 06 19 334 339 EN Eui-Suk JEONG Department of Laboratory Animal Medicine, College of Veterinary Medicine, Konkuk University, Seoul 05029, Republic of Korea AND Laboratory Animal Center, Daegu-Gyeongbuk Medical Innovation Foundation, Daegu 41061, Republic of Korea Jong-Hyung PARK Department of Laboratory Animal Medicine, College of Veterinary Medicine, Konkuk University, Seoul 05029, Republic of Korea Seung-Hyun RYU Department of Laboratory Animal Medicine, College of Veterinary Medicine, Konkuk University, Seoul 05029, Republic of Korea Soo-Young CHOI Department of Laboratory Animal Medicine, College of Veterinary Medicine, Konkuk University, Seoul 05029, Republic of Korea Kyoung-Sun LEE Laboratory Animal Center, Osong Medical Innovation Foundation, Chungbuk 28160, Republic of Korea Jong-Man KIM Laboratory Animal Center, Osong Medical Innovation Foundation, Chungbuk 28160, Republic of Korea Byung-Hwa HYUN Laboratory Animal Center, Osong Medical Innovation Foundation, Chungbuk 28160, Republic of Korea Yang-Kyu CHOI Department of Laboratory Animal Medicine, College of Veterinary Medicine, Konkuk University, Seoul 05029, Republic of Korea 2018 03 19 2019 06 19 Background: Recently, the use of common marmoset (Callithrix jacchus) has increased in biomedical research as an animal model. This study aimed to test fecal samples to monitor bacterial and parasite infections in common marmoset at the Laboratory Animal Center of Osong Medical Innovation Foundation in Korea. Methods: To monitor bacteria and parasites in common marmoset, we tested 43 fecal samples of 43 common marmosets by culture and parasitological test in 2014. Infection by Chilomastix mesnili was determined by PCR method. Results: We identified nonpathogenic bacteria such as Proteus mirabilis and Escherichia coli in feces of normal common marmosets. Interestingly, C. mesnili was isolated from a healthy common marmoset by fecal centrifugation concentration and PCR. The monkey infected with C. mesnili was treated with metronidazole. After the treatment, C. mesnili were not found in feces using fecal centrifugation concentration and PCR. Conclusion: This is the first case report of C. mesnili infection in common marmoset. Treatment with metronidazole is found to be highly effective in eradicating C. mesnili infection in common marmoset. https://ijpa.tums.ac.ir/index.php/ijpa/article/view/2061 https://ijpa.tums.ac.ir/index.php/ijpa/article/download/2061/951