Prevalence and potential risk factors associated with methicillin resistant Staphylococcus aureus infection in Dairy farms

Abstract

Objective: A cross sectional study was conducted between June 2017 and August 2018 in around Dakahlia governorate to identify  Methicillin resistant Staphylococcus aureus (MRSA) and to determine risk factors associated with the occurrence of mastitis in dairy cows.

Design: Cross sectional study

Animals and samples: 130 dairy cattle (744 samples) and 181 environmental samples (36 bedding, 37 bulk tank milk BTM, 27 feed  troughs, 27 water troughs, 27 milk linear and 27 worker’s nasal swabs), with a total of 925 samples were studied.

Procedures: Three  hundred and seventy-two quarters were examined to detect clinical and subclinica l mastitis by physical examinations and California  mastitis test. In addition, bacteriological isolation and identification of Staphylococcus aureus and MRSA were carried on the above milk  samples of above mentioned quarters, teat swabs and environmental samples.

Results: The overall prevalence of Staphylococcus aureus  and MRSA was 59.4 and 22.4, respectively. The MRSA were more prevalent in mastitic quarter (X₂ = 31.146, P-value = 0.000), Holstein Friesian breed (Pvalue = 0.021), Old aged dairy cattle (>8 years) (P-value = 0.000), Multiparous cows (P-value = 0.000), large herd size  (>=2000) (P-value = 0.000).

Conclusion and clinical relevance: The present result indicates that MRSA is a major cause of mastitis in dairy  farms at northern Egypt, where one of the key elements for controlling its spreading depends mainly on determining its potential  risk factors responsible for its existence