Influence of different types of sugar on overfeeding performance-part of meat quality.

Previous research in our lab showed that 10% glucose, 10% fructose, and 10% sucrose can induce lipid deposition in goose fatty liver formation process more efficiently. However, whether the overfeeding diet supplement with sugar can affect the meat quality is unclear. The aim of this research was to estimate the meat quality of geese overfed with overfeeding diet adding with different types of sugar. The results indicated there were no significant differences in the diameter of muscle fiber, the muscle fiber density, pH0, pH24, the meat color, the cooking loss, the drip loss, the shear force and the dry matter in breast muscle and thigh muscle between corn flour groups and three sugars groups (P > 0.05). The crude fat content of breast muscle in fructose group was significantly higher than that in sucrose group (P < 0.05); the inosinic acid content of leg muscle in fructose group was significantly higher than that in the sucrose group (P < 0.05); the ratios of essential amino acids to total amino acids (EAA/TAA) in the breast muscle of maize flour group, fructose group, sucrose group and glucose group were 42%, 35%, 32% or 34%;57%, 64%, 64%, and 62%, respectively; the ratios of essential amino acids to total amino acids in leg muscle of maize flour group, fructose group, sucrose group and glucose group were 31%, 33%, 35%, and 34%, respectively. The contents of C16:1 and C18:1 n-9c in breast muscle in fructose group were significantly higher than that in sucrose group (P < 0.05). Compared with maize flour group, the contents of C18:0 and C20:0 were lower in leg muscle of sugar group (P < 0.05). Compared with the maize flour group, the activities of hydrogen peroxide (H2O2) and glutathione peroxidase (GSH-PX) in breast muscle were higher than those of sucrose group (P < 0.05), the total antioxidant capacity (T-AOC) levels in breast muscle was higher than that of fructose group and sucrose group (P < 0.05). Cluster analysis and principal component analysis (PCA) showed that there was no difference in meat quality between maize flour and sugar group. In conclusion, the overfeeding with maize flour supplement with 10% sugar had no evident influence on the meat quality.

Mechanism of SCD Participation in Lipid Droplet-Mediated Steroidogenesis in Goose Granulosa Cells.

Stearoyl-CoA desaturase (SCD) is a key enzyme catalyzing the rate-limiting step in monounsaturated fatty acids (MUFAs) production. There may be a mechanism by which SCD is involved in lipid metabolism, which is assumed to be essential for goose follicular development. For this reason, a cellular model of SCD function in goose granulosa cells (GCs) via SCD overexpression and knockdown was used to determine the role of SCD in GC proliferation using flow cytometry. We found that SCD overexpression induced and SCD knockdown inhibited GCs proliferation. Furthermore, ELISA analysis showed that SCD overexpression increased the total cholesterol (TC), progesterone, and estrogen levels in GCs, while SCD knockdown decreased TC, progesterone, and estrogen levels (p < 0.05). Combining these results with those of related multi-omics reports, we proposed a mechanism of SCD regulating the key lipids and differentially expressed gene (DEGs) in glycerophospholipid and glycerolipid metabolism, which participate in steroidogenesis mediated by the lipid droplet deposition in goose GCs. These results add further insights into understanding the lipid metabolism mechanism of goose GCs.

Study on the effect of different types of sugar on lipid deposition in goose fatty liver.

Early research in our lab indicated that the effect of glucose, fructose and sucrose on the levels of triacylglycerol, and inflammatory factor was significantly different, and it is speculated that the regulatory mechanism of lipid deposition by different type of sugar in the liver is different. In order to explore lipid deposition difference mediated by different types of sugar (glucose, fructose, and sucrose) in goose fatty liver formation, this experiment was performed from cell culture, overfeeding experiment, and transcriptome analysis at 3 levels. Cell culture experiment results indicated that the levels of intracellular triglyceride, total cholesterol, and lipid content of fructose and sucrose treatment were significantly higher than those of glucose treatment (P < 0.05). In slaughter performance, the liver weight, the ratio of liver weight to body weight, feed conversion ratio (liver weight/feed consumption) were better in sucrose overfeeding group (P < 0.05). In addition, the liver of the sucrose overfeeding group contained a lot of unsaturated fatty acids, especially (n-3) polyunsaturated fatty acids (P < 0.05). Transcriptome analysis shown that the peroxisome proliferators-activated receptor (PPAR) signaling pathway is highly enriched in the fructose and sucrose overfeeding groups; cell cycle, and DNA replication pathways were highly enriched in the glucose overfeeding group. In conclusion, due to the decrease of lipids outward transportation and the anti-inflammation of unsaturated fatty acids, fructose, and sucrose have better ability to induce steatosis in goose fatty liver formation.