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In November 2015 the emergence of the first plasmid-encoded colistin resistance gene mcr-1 was detected in animals as well as human beings in China. Within the last couple of months, a multitude of further studies was performed, indicating a global spread of the plasmid encoded resistance gene. As in human medicine, colistin is one of the last therapeutic options for the treatment of multidrugresistant bacteria, the current situation has to be assessed critically. On the other hand in veterinary medicine, colistin is widely used for the treatment of diarrhoea in food-animals like pigs or poultry. Thus, indicating that the worldwide spread of the plasmid-encoded colistin resistance gene mcr-1 reflects a major topic at the interface of human and animal health. To evaluate the mcr-1 occurrence on farm level, bacterial cultures sampled on pig- as well as chicken-fattening farms during the years 2011 to 2013 were systematically screened for the presence of this gene. Primarily cultures deriving from pooled feces, boot swabs as well as dust samples, collected in a crosssectional study including 58 pig-fattening and 45 chicken-fattening farms throughout Germany were investigated by PCR. Subsequently single mcr-1 positive E. coli and one K. pneumoniae were isolated using MacConkey agar plates containing 2 μg/ml colistin. The received isolates are currently further investigated by using different phenotypic- as well as genotypic approaches. Based on the so far obtained results the mcr-1 gene occurrence for the years 2011 to 2013 can be assessed at a value of 26% of the investigated pig- as well as 24% of the investigated chicken-farms. Ongoing and thorough investigations of the current situation in livestock farms are highly recommended.