Unpredictable, sudden-onset bleeding in deer mice (Peromyscus maniculatus bairdii) after oral exposure to a gut-sterilising antibiotic cocktail

Abstract

Abstract Background: Animal models are valuable tools to investigate contributions of the gut microbiota to human disorders. Deer mice are studied for their expression of obsessive-compulsive-like behaviour, which has recently been associated with gut dysbiosis in this model. To this end, sterilisation of the gut microbiota by means of orally administered antibiotic cocktails, is a common procedure when studying the pathological role of dysbiosis. Methods: In this case report, we refer to six unexpected mortalities after exposing 26 adult deer mice (Peromyscus maniculatus bairdii) of both sexes to a gut sterilising regimen that consisted of ampicillin, vancomycin, imipenem, gentamycin, and amphotericin B. Results and conclusion: We recorded fatal bleeding episodes in four male and two female mice. While vancomycin is suspected to be the main agent of concern, future studies are needed to divulge the underlying mechanisms that resulted in the reported deaths.