Korean Journal of
Veterinary Service

This study was aimed to investigate the prevalence and antimicrobial resistance of Pseudomonas spp. isolated from bovine mastitis milk samples. A total of 50 (4.9%) Pseudomonas spp. was isolated from 1,023 samples, those collected between 2018 and 2021, derived from 110 dairy farms. The prevalence of the identified species of Pseudomonas isolates was as follows; P. aeruginosa (70.0%), P. fluorescens (14.0%), P. putida (10.0%), P. fragi (4.0%), and P. chlororaphis (2.0%). Most of somatic cell counts in the quarter milk carrying Pseudomonas spp. were less than 3,000,000 cell/ml (90.0%). The isolates of Pseudomonas spp. showed high susceptibility to cefepime (98.0%), ciprofloxacin (98.0%), ceftazidime (96.0%), and colistin (96.0%). The rate of antibiotic resistance in the isolates was highest to ceftiofur (92.0%), followed by the resistance rate to chloramphenicol (86.0%) and trimethoprim/sulphamethoxazole (80.0%). In addition, there is a remarkable difference in antimicrobial resistance pattern among Pseudomonas species. P. aeruginosa and P. putida showed a similar resistance pattern, whereas P. fluorescens showed exceptionally lower resistance to trimethoprim/sulphamethoxazole and chloramphenicol than that of the other species. This study showed that prevalence of Pseudomonas spp. other than P. aeruginosa were 30.0% in bovine mastitis milk, and the occurrence rate of antibiotic resistance were similar or higher level, compared with the previous reports on the mastitisderived Pseudomonas spp. isolated in Korea.

Keywords Antimicrobial resistance, Bovine mastitis, Pseudomonas spp., Somatic cell count

1. Banerjee S, Batabyal K, Joardar SN, Isore DP, Dey S, Samanta I, Samanta TK, Murmu S. 2017. Detection and characterization of pathogenic Pseudomonas aeruginosa from bovine subclinical mastitis in West Bengal, India. Vet World 10: 738.
   
2. Bogni C, Odierno L, Raspanti C, Giraudo J, Larriestra A, Reinoso E, Lasagno M, Ferrari M, Ducros E, Frigerio C, Bettera S, Pellegrino M, Frola I, Dieser S, Vissio C. 2011. War against mastitis: Current concepts on controlling bovine mastitis pathogens. Science against microbial pathogens: Communicating current research and technological advances 483-494.
3. Cheng WN, Han SG. 2020. Bovine mastitis: risk factors, therapeutic strategies, and alternative treatments—A review. Asian-Australas J of Anim Sci 33: 1699.
   
4. CLSI (Clinical and laboratory Standards Institute). 2019. Performance standards for antimicrobial susceptibility testing; 29th edition. CLSI document M100. 29th ed. CLSI, Wayne, PA.
5. Erskine R, Walker R, Bolin C, Bartlett P, White D. 2002. Trends in antibacterial susceptibility of mastitis pathogens during a seven-year period. J Dairy sci 85: 1111-1118.
   
6. Gomes F, Henriques M. 2016. Control of bovine mastitis: old and recent therapeutic approaches. Curr Microbiol 72: 377-382.
   
7. Halasa T, Huijps K, Østeras O, Hogeveen H. 2007. Economic effects of bovine mastitis and mastitis management: a review. Vet Q 29: 18-31.
   
8. Kang HJ, Kim IC, Kim JH, Son WG, Lee DS. 2001. Identification and antimicrobial susceptibility of microorganisms isolated from bovine mastitic milk. Korean J Vet Res 41: 511-521.
9. Kawai K, Shinozuka Y, Uchida I, Hirose K, Mitamura T, Watanabe A, Kuruhara K, Yuasa R, Sato R, Onda K, Nagahata H. 2017. Control of Pseudomonas mastitis on a large dairy farm by using slightly acidic electrolyzed water. Anim Sci J 88: 1601-1605.
   
10. Kim SE, Hah DY, Jang EH, Kwon HN, Jo SS, Kwon YT, Park DY, Lee KC, Kim JS. 2011. Survey of mastitis management and incidence of mastitis in high somatic cell count of bulk milk at dairy farms in the Gyeongnam. Korean J Vet Serv 34: 349-388.
    
11. Lee ES, Kang HM, Chung CI, Moon JS. 2007a. Antimicrobial susceptibility and prevalence of gram-negative bacteria isolated from bovine mastitis. Korean J Vet Res 47: 67-75.
12. Lee G, Kang HM, Chung CI, Moon JS. 2007b. Antimicrobial susceptibility and genetic characteristics of Streptococcus uberis isolated from bovine mastitis milk. Korean J Vet Res 47: 33-41.
13. Nam HM, Lim SK, Kang HM, Kim JM, Moon JS, Jang KC, Kim JM, Joo YS, Jung SC. 2009. Prevalence and antimicrobial susceptibility of gram-negative bacteria isolated from bovine mastitis between 2003 and 2008 in Korea. J Dairy Sci 92: 2020-2026.
    
14. Nam HM, Lim SK, Jang GC, Joung DY, Kim HJ, Lee CS, Jung SC. 2013 Culture results from quarter milk samples submitted to veterinary diagnostic laboratories during january~November 2012 in Korea. Prev Vet Med 37: 111-119.
    
15. Nam HM, Lim SK, Moon JS, Kang HM, Kim JM, Jang KC, Kim JM, Kang MI, Joo YS, Jung SC. 2010. Antimicrobial resistance of enterococci isolated from mastitic bovine milk samples in Korea. Zoonoses Public Health 57: e59-64.
    
16. NMC (National Mastitis Council). 2017. Laboratory Handbook on Bovine Mastitis, 3rd ed. New Prague: NMC, USA.
17. Ohnishi M, Sawada T, Hirose K, Sato R, Hayashimoto M, Hata E, Yonezawa C, Kato H. 2011. Antimicrobial susceptibilities and bacteriological characteristics of bovine Pseudomonas aeruginosa and Serratia marcescens isolates from mastitis. Vet Microbiol 154: 202-207.
    
18. Park HR, Hong MK, Hwang SY, Park YK, Kwon KH, Yoon JW, Shin S, Kim JH, Park YH. 2014. Characterisation of Pseudomonas aeruginosa related to bovine mastitis. Acta Vet Hung 62: 1-12.
    
19. Saidi R, Khelef D, Kaidi R. 2013. Subclinical mastitis in cattle in Algeria: frequency of occurrence and bacteriological isolates. J S Afr Vet Assoc 23;84: E1-5.
    
20. Schauer B, Wald R, Urbantke V, Loncaric I, Baumgartner M. 2021. Tracing Mastitis Pathogens—Epidemiological Investigations of a Pseudomonas aeruginosa Mastitis Outbreak in an Austrian Dairy Herd. Animals 11: 279.
    
21. Smith KL, Hogan JS. 1993. Environmental mastitis. Vet Clin North Am Food Anim Pract 9: 489-498.
    
22. Suleiman T, Karimuribo E, Mdegela R. 2018. Prevalence of bovine subclinical mastitis and antibiotic susceptibility patterns of major mastitis pathogens isolated in Unguja island of Zanzibar, Tanzania. Trop Anim Health Prod 50: 259-266.