Integrating phenotypic and genomic data to describe a Sicilian local cattle ecotype adapted to Mediterranean environments

Sicily hosts three local cattle populations: the officially recognized Modicana and Cinisara breeds, and the Siciliana ecotype, reared in the mountainous Nebrodi area. Socioeconomic changes, the lack of official recognition, and unrestricted crossbreeding with cosmopolitan breeds have accelerated genetic erosion, threatening the conservation of the Siciliana population. Here we combined phenotypic and genomic analyses to characterize the Siciliana cattle and gather information to support conservation strategies. Phenotypic data, including qualitative and morphometric traits, were collected from 32 individuals representative of the typical mountain ecotype. Genomic analyses were conducted using medium-density SNP data from 90 Siciliana individuals compared with 35 Italian and French breeds. Results showed a body conformation coherent with the adaptation to mountainous environments and extensive farming, characterised by a mesomorphic and dolichomorphic conformation, homogeneous qualitative traits, and a variable body types. Genomic analyses revealed moderate genetic diversity (Ho = 0.33), low inbreeding (0.04), and a distinct profile of genomic ancestry, whilst still grouping with the other Sicilian breeds. Introgression varied among farms and reflected different breeding practices, including crosses with Limousine, to increase meat yield, or Modicana, likely to benefit from its recognized breed status. Overall, our results suggest the uniqueness of the Siciliana ecotype but highlight significant genetic erosion due to extensive crossbreeding, emphasizing the need for targeted conservation actions.