ISOLATION AND IDENTIFICATION OF METHICILIN RESISTANT S. aureus FROM BOVINE MASTITIC MILK IN AND AROUND WOLAITA SODO, SOUTHERN ETHIOPIA
No Thumbnail Available
Date
2014-06
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
A cross sectional study was conducted from November 2013 to May 2014 in and around Wolaita Sodo town, Southern Ethiopia, to isolate and identify methicilin resistant S. aureus and their resistance to different antimicrobials and also identify risk factors associated with occurrence of dairy cow mastitis. A total of 257 dairy cows were included during the study period. Total of 1020 quarters were examined to detect clinical and subclinical mastitis by physical examinations of udder and milk and California mastitis Test (CMT), respectively. The prevalence of mastitis was 40.9%. Out of this, 4.66% and 36.18% were clinical and subclinical respectively. The univariate logistic regression showed that among potential risk factors considered from the farm attributes, age, milking hygiene, parity, lactation period, farm floor and previous mastitis treatment had significant (p=<0.05) effect on the prevalence of mastitis. However, breed was not a significant potential risk factor. 39 (15.1%) S. aureus was isolated and out of this, 8(3.11%) and 31(12.06%) were from clinical mastitis and subclinical mastitis respectively. The result showed a significant association of S. aureus with mastitis (p=0.025). The present study showed the resistance of S. aureus to penicillin G (100%), cefoxtin (71.8%), amoxicillin-clavulinic acid (61.5%), tetracycline (69.2%), streptomycin (66.7%), chloramphenicol (35.9%), sulphamethoxazole-trimethoprim (43.6%) and vancomycin (56.4%). In the present observation, 28 (71.8 %) S. aureus isolates not only showed MRSA but also multidrug resistance (MRSA) primarily to penicillin G, cefoxtin, tetracycline and streptomycin because of resistance to β-lactams and frequent use. Association of MRSA with age of cows was also highly significant (p = 0.000) and all MRSA were isolated from adult and old cows. 92.8% of MRSA isolates was found in previously mastitis treated animal showed significant association (p=0.001). The development of antimicrobial resistance is nearly always as a result of repeated therapeutic and/or indiscriminate use of them. Regular antimicrobial sensitivity testing helps to select effective antibiotics and to reduce the problems of drug resistance development towards commonly used antibiotics.
Description
Keywords
antibmicrobials, association, cross sectional, dairy cows, MRSA