SUMMARY

Aims of this study were to apply AFLP markers to assess the genetic diversity and to define a marker-assisted traceability system in local chicken breeds. Data were based on 107 cocks of three different local chicken breeds from Veneto region (Italy): Robusta (PRR: n=54), Pepoi (PPP: n=33) and Padovana (PPD: n=20). Chickens were individually identified at birth with wing tag and reared in four different herds using a free-range system. Genomic DNA was extracted from whole blood and AFLP analysis was performed according to the protocol described in Barcaccia et al. (1998). Values of expected heterozygosity (H) and polymorphism information content (PIC) at AFLP loci were calculated for each breed. Genetic similarities of all possible pairs of genotypes were estimates using a Jaccard index; the values obtained were subsequently used in a factorial analysis in order to define latent variables which explain the whole genetic similarity relation system between individuals. The average PIC index within breed was generally low: 24.1 % for PRR, 23.6 % for PPD and 17.2 % for PPP. The average heterozygosities of the three breeds for all markers were 29.5 % for PRR and PPD and 21.3 % for PPP. In the majority of cases (from 90 % to 100 % of individuals within breed), marker-assisted traceability system used in this research correctly identified the breed of cocks. Hence, results are promising to identify biological tissue (meat, gamets, embryo, etc.) from these local chicken breeds. However, the method used in this study should be improved in terms of cost reduction for single sample, work effort, reproducibility and accuracy of results obtained