The normalisation of CAPN gene expression in M. pectoralis superficialis in broiler lines differing in growth rate and their relationship to breast muscle tenderness.

The aim of this study was to assess mRNA abundance of calpain 1 (CAPN1) and calpain 3 (CAPN3) in breast muscle of 80 fast-growing (FG) and slow-growing broilers (SG) and relate gene expression in relation to growth and Warner Bratzler (WB) shear force of breast muscle. The expression of CAPN1 and CAPN3 genes was higher in the FG compared to the SG line, but significant results were obtained only for CAPN1. The CAPN1 mRNA level was strongly dependent on line and gender interaction. Lower values of shear force were observed in the FG line, where a higher level of calpain expression was shown. A new panel of housekeeping genes (RPL4 and SDHA) for normalisation of gene expression in muscle tissues could be used in other studies of gene expression in chicken.