Abstract:
A cross sectional study was conducted from November 2019 to April 2020 in Oebre
Markos Town, to isolate and identify Methicillin Resistant Staphylococcus aureus from
raw cow's milk and to evaluate their resistance pattern to different antimicrobials.
Purposive sampling technique was employed and 50 dairy farms were involved in the
study. From a total of 150 samples were collectedfrom pooled milk sample (50), milker's
hand swab (50) and container swab (50). 14 (9.3%) of them were found to be positive for
S. aureus. Out of 14 S. aureus isolates, 8(57.14%) tested positive for MRSA. Of which
(8(57.14%)), 5 (62.5%), 2 (66.6%), and 1(33.3%) were from pooled milk; Hand swab
from milker's and swab from containers, respectively. This study involved 50 respondents
of milking persons who practiced udder washing (56%) and drying (52%) before milking,
however; 96% did not use drying towel separately for the udder. while 80% did not
practiced washing of hands between milking, 98% practiced washing of hands before
milking. MRSA was identified using cefoxitin disk diffusion method. Of all S. aureus
isolates, 57.14% were found resistance to cefoxitin. MRSA isolates were found to be
sensitive to sulpha-trimethoprime (87.5%) and Gentamycin (87.5%) followed by
Erythromycin (75%), ciprofloxacin (62.5%), chloramphenicol (62.5%). Lowest sensitivity
was to tetracycline (25%). From all isolates of MRSA, 75 % of them developed multidrug
resistance. In conclusion, this study showed the existence of MRSA in dairy farms of
Debre markos town, where milker's hand and milking container were attributed to be the
main source of contamination. Therefore milking should be practiced under personal and
environmental hygienic conditions using clean and disinfected utensils.