Background
The meat quality of different pig breeds is associated with their different muscle tissue physiological processes, which involves a large variety of genes related with muscle fat and energy metabolism. Understanding the differences of biological processes of muscle after slaughter is helpful to reveal the meat quality development of different breeds. Therefore, 8 domestic Large Black pigs (BP), a domestic breed with high fat contents in meat, and 7 Cross-bred commercial pig (CP), which has a high feed efficiency with high lean meat, was used to investigate the differences of their meat quality and genotype.
Results
The average daily gain (ADG) and hot carcass weight (HCW) of CP were higher than BP, but the back-fat thickness of BP was higher than CP ( P < 0.05). The CP had higher a* but lower h value than BP ( P < 0.05). The metmyoglobin (MMb) percentage of CP was higher ( P < 0.05) than BP. The fat content and oxygen consumption of longissimus dorsi (LD) muscle in BP were higher ( P < 0.05) than CP. BP had higher SFA and MUFA content, but CP had higher PUFA content ( P < 0.05). The RNA-seq was applied to compare the genome differences between the two pig breeds. The RNA-seq data highlighted 201 genes differentially expressed between breeds ( P < 0.05), with 75 up-regulated and 126 down-regulated genes in BP compared with CP. The real-time PCR was used to validate the results of RNA-seq for 8 genes, and the genes related with lipid and energy metabolism were highly expressed in BP ( P < 0.05).
Conclusions
Based on the results, BP had superior general meat quality to CP, while the growth performance of CP was better, and the genotype differences between these two breeds may cause the meat quality and growth performance variance.