The Association Between Certain Liver Enzymes, Hematological Parameters, and Growth in the Common Carp (Cyprinus carpio) and Genetic Mutations of MSTN

Myostatin (MSTN), a negative regulator of skeletal muscle development, controls the size and number of muscle fibers through autocrine and paracrine signaling. This study aimed to investigate the effects of MSTN gene mutations on liver enzyme levels in the common carp (Cyprinus carpio) with an average weight of 250 ± 2.1g. The MSTN gene segment responsible for molecular detection and polymorphism analysis, as well as phenotypic variation arising from MSTN mutations, was amplified using the PCR technique. Sequencing revealed two genotypes: AG and GG, with distribution ratios of 17.65 and 82.35%, respectively (P< 0.01). Allelic frequencies were A = 0.09 and G = 0.91. The mean (±SE) levels of liver enzymes at the AG site were ALT: 25.08 ± 1.27a and AST: 117.05 ± 9.04a, whereas for genotype GG they were ALT: 22.13 ± 0.97a and AST: 85.71 ± 7.36b. While AST levels differed significantly between genotypes (P< 0.05), ALT levels did not show a significant difference. In terms of growth performance, the GG genotype was recorded with significantly higher values in weight gain (WG), daily growth rate (DGR), relative growth rate (RGR), and specific growth rate (SGR) compared to the AG genotype. Similar trends were observed for hematological parameters, including red blood cells (RBCs), white blood cells (WBCs), packed cell volume (PCV), and hemoglobin (Hb). This study contributes to a deeper understanding of the role of MSTN in muscle development and its broader implications for aquaculture and agricultural genetics. The findings may support future research on the genetic regulation of skeletal muscle formation and selective breeding strategies in fish.