Association of LEP- and CTSF-genotypes with levels of meat quality PSE, NOR and DFD in pigs of large white breed of Ukrainian selection

Aim. To study the distribution of genotypes by polymorphisms of the leptin (LEP SNP g.3469 T > C, LEP SNP g.2845 A > T) and cathepsin F (CTSF SNP g.22 C > G) genes according to the quality levels PSE, NOR and DFD meat in Large White pig breed of Ukrainian selection and to fi nd associations of genetic markers with the total indicator of meat quality. Methods. We studied meat samples (m. longissimus dorsi) from 102 pigs of Ukrainian Large White breed, raised to the weight at slaughter of 120 ± 5 kg in the experimental farm “Stepne” of the Poltava region, Ukraine. The ranking of muscle tissue was carried out according to the total indicator of meat quality (TM). PCR-RFLP analysis was used for DNA typing. The associations between genetic markers and TM were determined using ANOVA. Results. Genetic population analysis of Large White breed pigs of Ukrainian selection by genetic markers LEP SNP g.3469 T > C, LEP SNP g.2845 A > T and СTSF SNP g.22 C > G was carried out. The informative value of LEP SNP g.2845 A > T and СTSF SNP g.22 C > G, according to the calculated polymorphism information content, was optimal for associative studies (PIC = 0.311 and 0.373, respectively). The distribution of meat samples by quality levels PSE, NOR and DFD was performed. Most of them had traits of moderately expressed (n = 22) and weakly expressed (n = 59) PSE defect (light, soft, exudative meat). The calculated coeffi cients of Chuprov’s mutual conjugation between the genotypes for the studied SNPs and meat quality levels showed a moderate relationship between the genotypes for LEP SNP g.2845 A > T and CTSF SNP g.22 C > G and meat quality levels, К = 0.26 and 0.24, respectively. According to the results of ANOVA, the differences were found between homozygous and heterozygous CTSF SNP g.22 C > G genotypes in terms of the total indicator of meat quality. Conclusions. The meat of heterozygous pigs for CTSF SNP g.22 C > G (g.22GC) is characterized by a higher total indicator of meat quality (4.6) compared to the meat of homozygous animals g.22GG (4.2, p ≤ 0.05) and g.22CC (3.9, p ≤ 0.01).