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Simple Summary: Nutritional shortages or oversupply, such as fasting, restricted feeding, or overfeeding, often occur during animal production. Changes in nutritional status significantly affect animal health and production performance. Although the effect of nutritional changes on the expression of insulin-like growth factor-binding protein 2 (IGFBP2) in the liver is well established, the specific role of IGFBP2 in the response of the goose liver to these changes remains unclear. Further investigations are required to fully understand the involvement of IGFBP2 in this process. To address this, we used two types of animal models: the fasting/refeeding and overfeeding models of geese for in vivo study, and cultured goose primary hepatocytes for in vitro study. Data indicate that IGFBP2 expression in the goose liver was induced by fasting, but inhibited by refeeding and overfeeding. IGFBP2 overexpression in goose primary hepatocytes mainly inhibited the expression of the genes in the cytokine–cytokine receptor pathway, which was partly validated in in vitro models. These findings suggest that IGFBP2 mediates the response of the goose liver to changes in nutritional status, mainly through the cytokine–cytokine receptor pathway. Changes in the nutritional status of animals significantly affect their health and production performance. However, it is unclear whether insulin-like growth factor-binding protein 2 (IGFBP2) mediates these effects. This study aimed to investigate the impact of changes in nutritional and energy statuses on hepatic IGFBP2 expression and the mechanism through which IGFBP2 plays a mediating role. Therefore, the expression of IGFBP2 was first determined in the livers of fasting/refeeding and overfeeding geese. The data showed that overfeeding inhibited IGFBP2 expression in the liver compared with the control (normal feeding) group, whereas the expression of IGFBP2 in the liver was induced by fasting. Interestingly, the data indicated that insulin inhibited the expression of IGFBP2 in goose primary hepatocytes, suggesting that the changes in IGFBP2 expression in the liver in the abovementioned models may be partially attributed to the blood insulin levels. Furthermore, transcriptome sequencing analysis showed that the overexpression of IGFBP2 in geese primary hepatocytes significantly altered the expression of 337 genes (including 111 up-regulated and 226 down-regulated genes), and these differentially expressed genes were mainly enriched in cytokine–cytokine receptor, immune, and lipid metabolism-related pathways. We selected the most significant pathway, the cytokine–cytokine receptor pathway, and found that the relationship between the expression of these genes and IGFBP2 in goose liver was in line with the findings from the IGFBP2 overexpression assay, i.e., the decreased expression of IGFBP2 was accompanied by the increased expression of LOC106041919, CCL20, LOC106042256, LOC106041041, and IL22RA1 in the overfed versus normally fed geese, and the increased expression of IGFBP2 was accompanied by the decreased expression of these genes in fasting versus normally fed geese, and refeeding prevented or attenuated the effects of fasting. The association between the expression of these genes and IGFBP2 was verified by IGFBP2-siRNA treatment of goose primary hepatocytes, in which IGFBP2 expression was induced by low serum concentrations. In conclusion, this study suggests that IGFBP2 mediates the biological effects induced by changes in nutritional or energy levels, mainly through the cytokine−cytokine receptor pathway. [ABSTRACT FROM AUTHOR]

Nutrition and energy levels have an important impact on animal growth, production performance, disease occurrence and health recovery. Previous studies indicate that melanocortin 5 receptor (MC5R) is mainly involved in the regulations of exocrine gland function, lipid metabolism and immune response in animals. However, it is not clear how MC5R participates in the nutrition and energy metabolism of animals. To address this, the widely used animal models, including the overfeeding model and the fasting/refeeding model, could provide an effective tool. In this study, the expression of MC5R in goose liver was first determined in these models. Goose primary hepatocytes were then treated with nutrition/energy metabolism-related factors (glucose, oleic acid and thyroxine), which is followed by determination of MC5R gene expression. Moreover, MC5R was overexpressed in goose primary hepatocytes, followed by identification of differentially expressed genes (DEGs) and pathways subjected to MC5R regulation by transcriptome analysis. At last, some of the genes potentially regulated by MC5R were also identified in the in vivo and in vitro models, and were used to predict possible regulatory networks with PPI (protein–protein interaction networks) program. The data showed that both overfeeding and refeeding inhibited the expression of MC5R in goose liver, while fasting induced the expression of MC5R. Glucose and oleic acid could induce the expression of MC5R in goose primary hepatocytes, whereas thyroxine could inhibit it. The overexpression of MC5R significantly affected the expression of 1381 genes, and the pathways enriched with the DEGs mainly include oxidative phosphorylation, focal adhesion, ECM–receptor interaction, glutathione metabolism and MAPK signaling pathway. Interestingly, some pathways are related to glycolipid metabolism, including oxidative phosphorylation, pyruvate metabolism, citrate cycle, etc. Using the in vivo and in vitro models, it was demonstrated that the expression of some DEGs, including ACSL1, PSPH, HMGCS1, CPT1A, PACSIN2, IGFBP3, NMRK1, GYS2, ECI2, NDRG1, CDK9, FBXO25, SLC25A25, USP25 and AHCY, was associated with the expression of MC5R, suggesting these genes may mediate the biological role of MC5R in these models. In addition, PPI analysis suggests that the selected downstream genes, including GYS2, ECI2, PSPH, CPT1A, ACSL1, HMGCS1, USP25 and NDRG1, participate in the protein–protein interaction network regulated by MC5R. In conclusion, MC5R may mediate the biological effects caused by changes in nutrition and energy levels in goose hepatocytes through multiple pathways, including glycolipid-metabolism-related pathways. [ABSTRACT FROM AUTHOR]

To reduce the cutting force and cutting power consumption during harvest, the cutting mechanical properties of the root of little cabbage were studied. The cutting experiment was carried out using a texture analyzer, and the influence of the individual factors, the cutting bevel angle, the sliding angle, and the cutting gap on the maximum cutting stress and specific cutting energy were studied, respectively. On the basis of single factor experiments, multi-factor experiments were carried out using the central composite design scheme of the response surface method (RSM), and finally, the cutting parameters were optimized. The single factor test results showed that the maximum cutting stress and specific cutting energy first decreased and then increased with the increase in the cutting bevel angle, decreased with the increase in the sliding angle, and first dropped and then went up with the increase in the cutting gap. Response surface test results showed that the order of significance of factors affecting the maximum cutting stress of the root were the oblique angle, sliding angle, and cutting gap in sequence, and the order of the significance of factors affecting the specific cutting energy are cutting gap, oblique angle, and sliding angle. The interaction between the sliding angle and the cutting gap had a significant impact on the maximum cutting stress, and the interaction between the oblique angle and the cutting gap had a significant impact on the cutting energy. The optimal parameter combination is as follows: oblique angle of 9.1°, sliding angle of 30°, and cutting gap of 1.3 mm. At this time, the predicted maximum cutting stress was 7.43 × 104 Pa, and the specific cutting energy was 0.28 mJ mm−2. Finally, a verification experiment was carried out, and the errors of the predicted and measured values of cutting under the optimal parameter combination were 6.9% and 10.8%, respectively, showing that the cutting parameter optimization results were reliable. This research can provide data support for the design and improvement in the cutting device of the little cabbage combine harvester. [ABSTRACT FROM AUTHOR]