GENOMIC INVESTIGATION ON THE EFFECTS OF THE SELECTION IN SMALL RUMINANT SPECIES

Climate change as predicted for the upcoming decades in Italy poses increasing challenges for the biodiversity management of native Italian breeds. Consequently, it is vital to investigate the genetic impact of climate change on these breeds in terms of selection and adaptation. Given their variability and presence in different habitats, small ruminant species, such as goats and sheep, represent ideal subjects for studying the genetics that lays behind the adaptation to different environments. By introducing genomic data in the investigation of small ruminants we can observe how the genome of these various species and breeds has adapted to artificial selection and environment as well as provide useful information to breeders and their associations . In this thesis genomic tools were used to investigate the signs that adaptation and selection left on Italian small ruminants population with a particular focus on goats. We analyzed the biodiversity of 33 different Italian goat breeds and populations by identifying the interactions between their genotypes and the environment where they were raised by means of Landscape Genomics (the 1st paper). Then we examined how the different breeding systems and management differentiate them and what signatures are left in their genome by means of the Runs of Homozygosity (the 2nd paper). In the final paper we evaluated the relationships between values for genomic and pedigree inbreeding coefficients for six different case-study breeds of sheep and goats in order to provide breeders and their associations with more accurate estimates as well as useful and reliable data, thereby laying the foundation for the construction of genomic indexes for small ruminants in Italy.