Genetic Variability and Population Structure in the Sardinian Anglo-Arab Horse.
Authors: Giontella Andrea, Sarti Francesca Maria, Cardinali Irene, Giovannini Samira, Cherchi Raffaele, Lancioni Hovirag, Silvestrelli Maurizio, Pieramati Camillo
Journal: Animals : an open access journal from MDPI
Summary
# Editorial Summary: Genetic Variability and Population Structure in the Sardinian Anglo-Arab Horse Researchers used pedigree analysis and mitochondrial DNA sequencing to assess the genetic health and population dynamics of the Sardinian Anglo-Arab (SAA) breed, a historically significant Italian horse population with roots in Sardinia. With near-complete pedigree records available, the team calculated key population metrics including inbreeding coefficients (below 3%), effective population size estimates ranging from 185 to 457 depending on calculation method, and the ratio of effective founders to ancestors (3.68), findings that collectively point to a history of crossbreeding and possible population bottlenecks within the breed. The mitochondrial DNA evidence revealed substantial diversity in maternal lineages, particularly a strong L lineage presence likely resulting from Iberian horses recolonising the Mediterranean after the last Ice Age. Within the broader context of Italian horse breeds, the SAA demonstrates moderate genetic variability with managed but not concerning levels of inbreeding, suggesting the population remains viable for selective breeding programmes. For practitioners working with the breed—whether in competition, reproduction, or health management—these results indicate that structured breeding decisions can continue with confidence, though the documented crossbreeding history warrants consideration when establishing breeding goals or investigating breed-specific health concerns.
Read the full abstract on PubMed
Practical Takeaways
- •The breed shows manageable inbreeding levels (<3%) despite a bottleneck history, suggesting current breeding practices are maintaining genetic health reasonably well
- •Low effective founder ratio (3.68) indicates breeders should monitor future crosses carefully to avoid rapid inbreeding accumulation in this relatively small population
- •High mitochondrial variability suggests diverse maternal lines are available for breeding decisions, providing flexibility in mare selection
Key Findings
- •Pedigree completeness in Sardinian Anglo-Arab horses was near 100% with inbreeding coefficient and average relatedness both below 3%
- •Effective population size varied by calculation method: Ne_1 = 456.86, Ne_2 = 184.75, and Ne_3 = 209.31, indicating crossbreeding and bottleneck phenomena
- •Ratio of effective founders to number of ancestors was 3.68, suggesting limited founder diversity relative to total ancestors
- •Mitochondrial analysis revealed substantial variability with notable L lineage contribution, likely from Iberian Peninsula re-colonization post-Last Glacial Maximum