Contamination and antibiotic resistance of multiple pathogens in raw milk from different farms of different regions of China in 2019

Abstract

ObjectiveTo understand the contamination of pathogens and the antibiotics resistance characterization in raw milk in China.MethodsA total of 53 raw milk samples collected from 43 pastures in different regions in China from September to November in 2019 were detected the contamination of six pathogens, and isolates were tested for the antibiotic resistant ability.ResultsThe contamination rates of Escherichia coli, Staphylococcus aureus, Bacillus cereus and Listeria monocytogenes were 62.26%(33/53), 20.75%(11/53), 5.66%(3/53)and 3.77%(2/53), respectively. The detection of Cronobacter and Salmonella were negative. A total of 117 isolates were selected for antibiotics resistance test and 58 strains were resistant to antibiotics, accounted for 49.57%(58/117). 33 of 90 gram-negative strains were resistant strains, accounted for 36.67%(33/90). 25 of 27 gram-positive bacteria were resistant strains, accounted for 92.59%(25/17).ConclusionThe bacterial contamination in raw milk collected from pastures in different regions was quite different, and showed a downward trend with the decrease of temperature. Isolates from raw milk showed a high multiple antibiotics resistance rate, suggesting a cautious control of veterinary antibiotics should be adopted.

Keywords

• raw milk
• pathogens
• contamination rate
• antibiotics resistance