Testing a Farm Animal Model for Experimental Kidney Graft Transplantation: Gut Microbiota, Mycobiome and Metabolic Profiles as Indicators of Model Stability and Suitability

The aim of this pilot study was to comprehensively evaluate the gut microbiota, mycobiome, and metabolomic profile of six 4-month-old crossbred pigs (A–F) originating from the same litter and from a specific breeding facility intended for preclinical transplantation experiments, in order to assess their physiological uniformity and identify potential health-related risks prior to inclusion in a kidney transplantation study. The results demonstrated an overall high degree of microbial and metabolic uniformity among the animals, confirming the stability and suitability of the selected breeding source for experimental purposes. At the same time, several individual differences of potential clinical relevance were observed. Animals A, E, and F exhibited signs of microbial and metabolic imbalance, including reduced diversity, increased oxidative activity, and the presence of potentially pathogenic taxa (Porphyromonadaceae bacterium DJF B175, Aspergillus). In contrast, animals B, C, and D showed a balanced metabolic and microbial profile without pathological deviations. The obtained results highlight the importance of preoperative assessment of the gut bacteriome, mycobiome, and metabolome when selecting animals for transplantation experiments. Such a selective screening approach may contribute to the early identification of physiological deviations, reduction of interindividual variability, and increased reliability and translational potential of preclinical studies.