Work

Study on the Development and Formation Specifics of Longissimus Dorsi Muscles in Ziwuling Black Goats

Year: 2025

Type: article

Abstract: To clarify the relationship between muscle development and meat quality in Ziwuling black goats, this study used the longissimus dorsi muscle of 6-month-old and 12-month-old goats as samples. With HE staining, fast–slow myofiber immunofluorescence double staining, and transcriptome sequencing, this study analyzed muscle structure, myofiber type transformation, and molecular regulation. Results showed that 6-month-olds had higher myofiber density and smaller diameter; 12-month-olds showed myofiber hypertrophy (larger diameter); immunofluorescence revealed more fast-twitch myofibers (Type II) at 6 months and increased slow-twitch ones (Type I) at 12 months. Transcriptome sequencing identified 387 differentially expressed genes (DEGs: 156 upregulated, 231 downregulated). GO analysis indicated that DEGs are involved in skeletal muscle growth, cAMP biosynthesis, etc.; KEGG analysis showed enrichment in arginine–proline metabolism and AMPK/MAPK signaling pathways (AMPK regulates fatty acid metabolism genes like ACACB/CPT1A; arginine–proline metabolism relates to muscle maturation). WGCNA clustered genes into nine modules (MEblue correlated with myofiber density/MAPK; MEgreen correlated negatively with diameter but positively with density, involving PPARGC1A/AMPK). In conclusion, protein nutrition at 6 months (promote myofiber proliferation) and regulating energy intake at 12 months (improve meat quality) are recommended, and 12 months is the optimal slaughter age.

Source: Animals

DOI: 10.3390/ani15223265