L’espressione fenotipica dei caratteri di qualità della carne e la variabilità genetica di vitelloni di razza Chianina

In previous works several microsatellites with alleles significantly linked to meat quality traits (chemical composition, colour traits, water holding capacity and tenderness) have been pointed out. The aim of this research was to evidence if the animals with similar phenotypic quantitative expression of meat quality traits present also a high genetic similarity and some alleles with a particularly high frequency. Four different groups of animals have been identified by cluster analysis with the link "Sum of Square" method on meat quality traits of 87 Chianina bulls, 23, 15, 25 and 24 subjects grouping respectively in the clusters 1, 2, 3 and 4. For this study 25 microsatellites were analysed and genetic similarities within and among clusters were estimated using the Individual Multilocus Genotype (IMG). The average similarities within the groups resulted respectively of 0.523, 0.470, 0.471 and 0.507, the average similarity within the population being 0.488. The four groups of meat quality traits showed a very high variability among them than within each one; they presented also alleles with different frequencies with respect to the other groups.