Some instrument failure and methodological issues have significantly delayed the project and most results were only obtained within the four months prior the action end.
Listed below, are the preliminary results for each analyses performed.
Microbiomes: At the genus level, the gut microbiota composition was dominated by Clostridium> Romboutsia> Proteus> Ezakiella> Bacteroides> Paeniclostridium> Peptoniphilus> Vagococcus> Peptostreptococcus> Enterococcus> Tissierella> Anaerococcus. We characterised the health status of the minks by quantifying the following pathogenic bacteria, Enterococcus faecalis, Ralstonia pickettii, Salmonella enterica and Serratia spp. in four organs (kidney, spleen, lung, lymph node). Ralstonia pickettii was the most abundant pathogen and has been detected in the lymph node, kidney and spleen, while in lungs it was the second most abundant bacteria after Metamycoplasma orale. Further analyses will be performed to associate gut microbiota composition to the abundance of pathogens in the four organs analyzed.
Diet: Out of 15 samples (stomach content or feces) we were able to obtain prey DNA for only 7 individuals (we used COI gene metabarcoding) . DNA from the freshwater fish Phoxinus bigerri was detected in three individuals, we also detected DNA of micro-mammals (Crossidura russula, Rattus norvegicus), amphibians (Rana temporaria) and other freshwater fish species (Salmo trutta, Leuciscus burdigalensis, Acanthobrama persidid, Squalius cephalus, Gobio lozanoi).
Pollutants: In the 31 muscle samples, the antibiotic trimetoprime was only detected in three individuals and carbamazepine, a drug to prevent and control seizures, was detected in one individual. Yet in one blood sample used to validate the extraction method for metabolomic analyses, we were able to detect more pharmaceuticals. For instance, we were able to detect three synthetic hormones: altrenogest a synthetic progestin commonly used to synchronize estrus in livestock; norethisterone acetate a progestin which can be used in birth control pills, and methylprednisolone a medication used to reduce inflammation. In addition, we were also able to quantify other environmental pollutants in most whole blood samples such as polycyclic aromatic hydrocarbons and phtalates.
Fecal cortisol: Cortisol concentrations in fecal samples ranged from 3.45 to 168.5 pg/mg dw, in the sub-sample in which these values are available, cortisol concentration will be added as a predictor in the models to explain gut microbiota composition.
Metabolomics: Whole blood samples were extracted with MeOH and MeOH/ACN and metabolomic analyses are undergoing.
