Development of the first microsatellite panel for Murciana chicken as a method of native breed conservation

The conservation of native poultry breeds is essential to ensure the continuity of valuable genetic resources, most of which are threatened by the expansion of industrial poultry farming. Management and genetic selection strategies supported by molecular tools, such as microsatellites, are key to guaranteeing their preservation. In this study, we developed and validated a multiplex panel of 22 microsatellites optimised for the Murciana local chicken breed, with the aim of characterising its genetic variability and assessing its efficiency for parentage assignment. The selected markers were distributed into two complementary panels to avoid fragment overlap and maximise allelic resolution. Genetic diversity analysis revealed moderate variability, with parameters such as the mean number of alleles (Na ≈ 5.05), observed heterozygosity (Ho ≈ 0.50), expected heterozygosity (He ≈ 0.54), and polymorphic information content (PIC ≈ 0.48), showing values comparable to or higher than those reported for several other local breeds. These results indicate that the Murciana breed retains a relatively broad genetic base, although signs of genetic drift and a slight excess of homozygosity highlight the need for management strategies focused on allele retention. In addition, the combined panel achieved near-complete parentage exclusion probabilities (≈ 1.000), successfully assigning up to 85% of pair of parents, a 100% of paternities, and between 84% and 100% of maternities depending on the scenario. Therefore, the multiplex panel provides a practical tool for conservation management, enabling inbreeding control and genetic monitoring to support the long-term viability of the Murciana breed.