Relationship between VRTN gene polymorphism and growth, slaughter and meat quality traits in three polish pig breeds

Earlier studies have shown that insertion/deletion polymorphism (g.20311 20312ins291) in vertnin (VRTN) gene is associated with number of vertebrate in pigs. Because vertebral number determines the size of important meat cuts and influences carcass conformation, the aim of this study was to estimate the relationship between VRTN gene polymorphism and growth, slaughter and pork quality traits including texture parameters. Investigations were carried out on 526 pigs represented three breeds: Polish Landrace, Polish Large White and Pulawska. VRTN gene polymorphism was determined by PCR methodology. Association study was performed for each breed separately. It was demonstrated that the analyzed polymorphism had significant influence on several economically important porcine traits. Among growth traits VRTN genotypes were associated with test and lifetime daily gains, number of days on test (p <= 0.05) and age of slaughter (p <= 0.01, ps0.05). For carcass parameters, relationships were noticed for carcass yield (p <= 0.01), weight of loin and its area, average backfat thickness and weight of primary cuts (p <= 0.05). Taking into consideration meat quality, VRTN polymorphism influenced intramuscular fat content, meat colour (yellowness) and pH24 (p <= 0.05). For texture parameters, it was correlated with toughness, cohesiveness, chewiness (p <= 0.01, p <= 0.05) and firmness (p <= 0.05) measured in M. longissimus dorsi and M. semimembranosus. Only intramuscular fat content, chewiness of ham, carcass yield and cohesiveness of loin showed unequivocal tendency. In case of the first trait, each breed Wt/Wt genotype was associated with its highest values (p <= 0.05), while the second and third traits, Q/Q genotype was correlated with its lowest values (p <= 0.01, p <= 0.05). Highest loin cohesiveness was observed in animals with Wt/Q genotype (p <= 0.01, p <= 0.05).