Amoxicillin-clavulanic acid and ciprofloxacin-treated SPF mice as gnotobiotic model

Abstract

The experiment was carried out on 24 SPF BALB/c female mice and lasted for 15days with a 5-day antibiotic (ATB) treatment and then 10days without ATB treatment. The aim of our study was to acquire an animal model with reduced and controlled microflora and, at the same time, to ensure that the good health of these animals is maintained. Per oral administration of amoxicillin and clavulanate potassium in Amoksiklav (Sandoz, Slovenia) at a dose of 387.11mg/kg body weight (0.2ml of dilution per mouse) and subcutaneous administration of ciprofloxacin in Ciloxan (Alcon, Spain) at a dose of 18.87mg/kg body weight (0.1ml of dilution per mouse) were performed every 12h during first 5days of experiment. Five-day treatment with ATB led to a reduced survivability of microorganisms in faeces (28.33±0.43% on day 2) and caecum content (28.10±1.56%), where no cultivable microorganisms in faeces were present. Ten-day convalescence of decontaminated animals under gnotobiotic conditions prevented recovery of species diversity in mice gut microflora. This was reduced to two detectable cultivable species, namely Escherichia coli (GenBank KX086704) and Enterococcus sp. (GenBank KX086705) which were capable to restore its metabolic (CRL 2012) and morphological potential (Baratta et al. Histochem Cell Biol 131:713-726, 2009) within physiological range. Animals obtained under this procedure can be used in further studies. As a result, we created a mouse gnoto model with reduced and controlled microflora without alteration of the overall health status of the respective animals.