Abstract:
Milk is a vital source of nutrients for both humans and animals, and it must be free of
potentially hazardous microorganisms. A cross-sectional study was undertaken from
December 2022 to June 2023 to investigate milk handling practices and to estimate the
prevalence, associated risk factors, and antibiotic susceptibility profile of S. aureus isolates in
selected dairy farms in Dire Dawa, Ethiopia. Face-to-face interviews with 100 respondents
using a structured questionnaire based on their familiarity with the farm were conducted to
assess the potential risk factors for S. aureus contaminations in milk. Besides, a total of 132
lactating cow samples were gathered using a simple random sampling technique from a
selected dairy farms and tested using standard microbiological procedures. The disc diffusion
method was also used to analyze the isolates' antibiotic susceptibility profiles. In the study
area about milk handling practices, among the total of 100 interviewed respondents, 57.00%,
70.00%, 47.00%, 86.00%, 43.00%, 86.00%, 63.00%, 40.00%, 31.00%, and 24.00%
interviewers were experienced hand washing before milking, uses plastic milking equipment,
uses detergent to clean bucket, randomly milking, milking of mastitis animals, cleaning barn
once per day, consumed raw milk, GIT disturbance while drinking raw milk, had awareness
on milk born infection, and acquiring illness, respectively. On the other hand, all of them
practiced storing milk at room temperature and in plastics. Of all respondents, 63.00% kept
milk up to 2 hours before use. The overall recorded prevalence of S. aureus was 18.2%
(24/132). The prevalence of S. aureus from milk, hands of milkers, and equipment swabs
were 15.9%, 29.2%, and 25.0%, respectively. There was significant statistical variation
between the prevalence of S. aureus concerning farm categories, age, parity, lactation stage,
udder and leg hygiene, and history of mastitis cow (p<0.05). Moreover, the isolate was found
to be susceptible to Sulphamethezole (83.3%), and Vancomycin (66.7%) whereas strongly
resistant to Penicillin (83.3%). The study found antibiotic-resistant S. aureus in raw milk
cows and swabs, as well as poor milk handling, practices, and raw milk-consuming behavior
in the study area. To protect against milk contamination with S. aureus and sanitary milk
handling practices in the study area, dairy producers should be educated on correct milk
handling and hygiene practices.
