RESEARCH ARTICLES

Molecular characterisation of antimicrobial resistance in coagulase negative staphylococci isolated from bovine subclinical mastitis
S. Anaina, K. Vijayakumar, K. Justin Davis, R. L. Rathish and B. K. Mani

doi: https://doi.org/10.51966/jvas.2023.54.1.153-159

Journal of Veterinary and Animal Sciences.2023.54(1):153-159

Author Details

S. Anaina: MVSc Scholar, Department of Veterinary Epidemiology and Preventive Medicine, College of Veterinary and Animal Sciences, Mannuthy, Thrissur-680651, Kerala, Kerala Veterinary and Animal Sciences University, Pookode, Wayanad, India.

K. Vijayakumar: Dean, College of Veterinary and Animal Sciences, Mannuthy, Thrissur, Kerala Veterinary and Animal Sciences University, Kerala, India.

K. Justin Davis: Assistant Professor, Department of Veterinary Epidemiology and Preventive Medicine, College of Veterinary and Animal Sciences, Mannuthy, Thrissur-680651, Kerala, Kerala Veterinary and Animal Sciences University, Pookode, Wayanad, India.

R. L. Rathish : Assistant Professor, Department of Veterinary Epidemiology and Preventive medicine, College of Veterinary and Animal Sciences, Pookode, Wayanad-673576, Kerala Veterinary and Animal Sciences University, Kerala, India.

B. K. Mani : Associate Professor, Department of Veterinary Microbiology, College of Veterinary and Animal Sciences, Mannuthy, Thrissur-680651, Kerala, Kerala Veterinary and Animal Sciences University, Pookode, Wayanad, India.

 

Article History

Received: 30.10.2022 Accepted: 16.12.2022 Published online: 31.03.2023

Corresponding author: S. Anaina

e-mail : anainasperumpillil @gmail.com

Citation : Anaina,S., Vijayakumar,K., Justin Davis,K., Rathish,R.L. and Mani,B.K. 2023. Molecular characterisation of antimicrobial resistance in coagulase negative staphylococci isolated from bovine subclinical mastitis. J. Vet. Anim. Sci. 54(1):153-159

DOI: https://doi.org/10.51966/jvas.2023.54.1.153-159



Abstract


Coagulase negative staphylococci (CNS) are emerging as the most prevalent causative agent of bovine mastitis. They are resistant to many commonly used antibiotics due to the presence of antimicrobial resistance (AMR) genes. A study was conducted to evaluate the AMR profiling of CNS isolated from bovine subclinical mastitis.Coagulase negative staphylococci were isolated from 49 (44.95 per cent) of the subclinical mastitis samples. Disc diffusion assay revealed that highest resistance was shown against gentamicin (42.85 per cent) followed by methicillin (32.6 per cent), ceftriaxone – tazobactam (24.48 per cent), enrofloxacin (20.4 per cent), tetracycline (16.32 per cent) and least resistance to cotrimoxazole (4 per cent). Genotypic characterisation of AMR genes such as mecA, aacA-aphD and norA by PCR was done for determining resistance to methicillin, gentamicin and fluroquinolone resistance. The CNS carried aacA-aphD, norA and mecA in 44.89 per cent, 32.65 per cent and 14.28 per cent, respectively. Comparison of phenotypic and genotypic characterisation of AMR in CNS was carried out by McNemar test and it was found that there was significant difference between the presence of mecA gene and methicillin resistance. There was no significant difference noticed forcharacterisation of phenotypic and genotypic AMR of CNS for gentamicin and fluroquinolone resistance.

Keywords: Coagulase negative Staphylococci, antimicrobial resistance, methicillin, gentamicin, fluroquinolones