Genetic diversity of old chicken breeds kept in Poland.

The aim of this study was to compare the genetic variation of five local chicken breeds reared in Poland. Twenty-seven microsatellite markers were investigated in 138 birds belonging to five breeds: Miniature Cochin (MCO), Gold Italian (GI), Green Legged Partridge (GLP), Silver Italian (SI) and White Leghorn (WL). One hundred eighty five alleles were detected in the overall population, with a mean number of 6.85 ± 3.32 alleles per locus. For the local breeds, the observed and expected heterozygosity ranged from a minimum of 0.287 to a maximum of 0.458 and from 0.397 to 0.499 for the GI and SI breeds, respectively. The overall population heterozygote deficiency was 0.430, the average Wright’s inbreeding coefficient (FIS) was 0.061 and the heterozygote deficiency due to breed subdivision was 0.393. Wright’s fixation index was slightly positive for all breeds excluding MCO (FIS = -0.476) and the estimated molecular inbreeding (fij) within breed ranged from 0.296 (GLP and SI) to 0.361 (WL) evidencing limited coancestry. Mean allelic richness, obtained with rarefaction method based on sixteen observations, was 2.12 being the WL the less variable (1.79). Tomiuk and Loeschcke’s DTL genetic distance values were used to draw a neighbornet network which separated the cluster made of MCO and GLP from the cluster of GI, WL and SI. The results arising from our microsatellites analysis represent a starting point for the valorization of these local Polish chicken breeds for monitoring and preserving their genetic variability.