Faecal Pellets as a Non-Invasive Source for DNA-Based Monitoring of Lagomorphs

Introduction: Faecal DNA is increasingly used in non-invasive genetic studies, offering a valuable tool for wildlife research, especially for elusive or protected species. It enables genetic analysis with minimal or no impact on animal welfare. Aims: Here we review scientific publications using faecal pellets as a source of DNA in wild lagomorphs, provide a critical overview of field and laboratory methodologies and provide suggested improvements for future genetic studies. Methods: Using the Scopus database, 45 publications from 1996 to 2024 were identified and analysed. Key aspects examined include sampling strategies, storage methods, DNA extraction protocols, molecular markers, and the intended applications of faecal DNA. Results: Although lagomorphs are widely studied, only a limited number of investigations used faecal pellets as a DNA source. These focused on 7 genera and 15 species, mainly Lepus (69%) and Sylvilagus (33%). Most studies were conducted in North America (n = 20) and Europe (n = 16), addressing species and individual identification, sexing, hybridisation and methodological validation. Mitochondrial DNA sequencing and microsatellite genotyping were the most common applications, respectively, for species determination and individual identification or population-level analyses. Discussion: This review highlights the usefulness of faecal pellets for genetic investigations on this taxon; however, improvements are needed. We prompt for methodological standardisations and for the development of taxon-specific SNP panels that could assure data reproducibility and comparability. We are confident that this review will provide a valuable starting point for future studies and assist researchers starting non-invasive genetic investigations on lagomorph populations.