马身猪高肌内脂肪含量形成的机制研究

he intramuscular fat (IMF), or marbling, is one of major factors affecting pork quality, and its content can influence the palatability and tenderness of meat. The Mashen pigs is well known for their high IMF, but the mechanism remains unclear. In present study, the Mashen pigs and Large white pigs (30 d and 180 d after birth) were used to explore the possible mechanism of higher IMF in Mashen pigs. The IMF contents were determined by Soxhlet extractor method, and the candidate key genes involved in adipogenesis by both Real-time PCR and Western blot. The results showed that the Mashen pig possessed higher IMF content in skeletal muscle. Real-time PCR results indicated that mRNA expressions of C/EBPα (P < 0.05), PPARγ (P < 0.01), Zfp423 (P< 0.05) and C/EBPβ（P < 0.05）were higher in Mashen pigs compared with Large white pigs. Accordingly, the protein contents of PPARγ (P< 0.05), C/EBPα (P < 0.001) and FABP4 (P < 0.001) were higher in Mashen pigs. The data suggest that the higher IMF content in Mashen pigs may attributed to the higher adipogenesis potential, which can provide basic data for further exploring the IMF formation in skeletal muscle of pigs.