Histological characteristics of the musculus longissimus lumborum et thoracis muscle fibres in pigs in relation to selected RYR1, MYOG, MYOD1 and MYF6 genotypes

Abstract

Histochemical and biochemical muscle fibre properties are the factors that influence the quantitative and qualitative characteristics of pork meat. The aim of the study was to assess the influence of genetic effects of selected genetic markers MyoD genes and RYR1 on the achieved indicators of muscle fibres in the musculus longissimus lumborum et thoracis (MLLT). The study included a total number of 216 hybrid pigs with the mean slaughter weight of 123 kg. Gene polymorphism was determined by the PCR-RFLP method. The gene polymorphism was determined in the RYR1, MYOD1, MYOG, and MYF6 genes. Muscle fibre types from MLLT were identified. Concerning the RYR1 gene, the study found that homozygous-dominant animals reached a lower number of type I (8.35 vs. 10.52; P < 0.05) and a higher number of IIA (3.66 vs. 2.10; P < 0.05) and a higher number of IIB (76.61 vs. 67.91; P < 0.05). The maximum number in all types of muscle fibres reached BB genotype of the MYOG gene (type I: 14.02; IIA: 18.47; IIB: 83.08; P < 0.05). The AA genotype of the MYOD1 gene showed the lowest (P < 0.05) number of muscle in all fibre types (type I: 9.20; IIA: 0.85; IIB: 69.23). The influence of individual genotypes of selected genes on the selected muscle fibre characteristics was proven. The obtained results confirm the possibility of affecting the quality of pork with genomic selection of MyoD genes family.