Tropical Animal Health and Production

, Volume 51, Issue 7, pp 2079–2084 | Cite as

Bacteriological quality and safety of ready-to-consume milk and naturally fermented milk in Borana pastoral area, southern Ethiopia

  • Kebede AmenuEmail author
  • Delia Grace
  • Shemsu Nemo
  • Barbara Wieland
Short Communications


Milk and milk products play an important role in the diet of pastoralists in Ethiopia. However, only few studies have been conducted on the microbial contamination of milk and milk products in pastoral areas. Therefore, the objective of the present study was to assess the hygiene and safety of ready-to-consume milk and traditionally produced fermented milk products (yogurt) in Borana. A total of 203 raw milk and milk product samples collected from different points along the milk production and handling chains were tested for Escherichia coli, E. coli O157:H7, and Staphylococcus aureus. E. coli was detected in 51.7% of the analyzed samples with a mean count of 2.5 logCFU/ml. The study revealed that 10.8% and 2.5% of the milk and dairy product samples harbor S. aureus and E. coli O157:H7, respectively. Detection of E. coli O157:H7 in ready-to-consume milk has potential health implications for consumers in an area where raw milk consumption is common. To our knowledge, this is the first report of the isolation of E. coli O157:H7 from milk in pastoral systems in Ethiopia.


Escherichia coli O157:H7 Staphylococcus aureus Milk contamination Microbiological safety Borana Ethiopia 



Sample collection and laboratory analysis were undertaken when Kebede Amenu and Shemsu Nemo were affiliated with Hawassa University and we thank the University for the provision of laboratory space for the microbiological analysis.

Authors’ contributions

KA: conceived the research idea, wrote the protocol, supervised lab works, performed data analysis and drafted the initial manuscript, and revised the manuscript

SN: involved in proposal write-up, microbiological analysis, and manuscript preparation

BW, DG: supervised the research and made substantial intellectual contribution in the designing of the study, preparation of the study protocols; result interpretation and manuscript preparation. All authors read and approved the final manuscript.

Funding information

This study was initially supported through the CGIAR Research Program (CRP) on Livestock and Fish and since 2017 through CRP Livestock. Kebede Amenu was supported through DAAD (German Academic Exchange Service) Fellowship.

Compliance with ethical standards

Conflict of interest

The authors declare that there are no competing interests.

Ethics approval and consent to participate

The research protocol for this study has been approved by the Ethics Committee of the College of Veterinary Medicine and Agriculture of Addis Ababa University for milk sample collection from individual animals.

Consent for publication

The authors declare that the manuscript does not contain any personally identifiable information.


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Copyright information

© Springer Nature B.V. 2019

Authors and Affiliations

  1. 1.Department of Microbiology, Immunology and Veterinary Public Health, College of Veterinary Medicine and AgricultureAddis Ababa UniversityBishoftuEthiopia
  2. 2.International Livestock Research InstituteAddis AbabaEthiopia
  3. 3.International Livestock Research InstituteNairobiKenya
  4. 4.Faculty of Veterinary MedicineHawassa UniversityHawassaEthiopia

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