To explore the effects of supplementing a basal diet with green sweet sorghum stalks on the gut microbiota in geese, one hundred and twenty 28-day-old geese were divided into two groups. Group 1 was fed a basal diet and group 2 was fed 92% of the same basal diet with green sweet sorghum stalks ad libitum for 42 days. Three male geese from each group were killed at 70 days old, four gastrointestinal tract segments (duodenum, jejunum, ileum, and caecum) were collected, and the hypervariable V4 region of the bacterial 16S rRNA gene was sequenced. There were obvious changes of microbiome in the caecum compared with the other three intestinal segments after green sweet sorghum stalks were added to the diet. Group 2 had significantly higher alpha diversity in the caecum compared with group 1 (P <0.05). The phyla of bacterial communities in the caecum differed. Group 2 had more abundant Bacteroidetes and Firmicutes, but Proteobacteria were more abundant in group 1. At genus level, Bacteroides was more prevalent in group 2, as were Prevotella and YRC22 (P <0.05). Functional analysis revealed that the carbohydrate metabolism, membrane transport, endocrine system and digestive system metabolic pathways were overrepresented in group 2. In conclusion, caecal microbes might play an important role in digesting green sweet sorghum stalks in geese.

ABSTRACT The objective of the study was to investigate the mechanism by which dietary energy concentration regulates laying performance in geese. Eighty 558-day-old female Sichuan White geese were randomly allotted to two dietary treatments, each treatment was fed 1 of 2 experimental diets containing 10.00 (deficient) or 11.80MJ/kg metabolizable energy (sufficient) for 30 days. Laying performance, hormone concentration and gene expressions in hypothalamus-pituitary-gonadal axis were examined in geese. Birds fed the sufficient-energy diet had significantly higher average egg weight, daily laying rate, and lower feed to egg ratio than those fed the deficient-energy (p<0.05). The birds fed sufficient-energy diet had higher concentration of serum insulin like growth factor 1 (IGF-1), gonadotropin-releasing hormone (GnRH), follicle-stimulating hormone (FSH) and estradiol (E2) than those in deficient-energy diet (p<0.05). The mRNA expression levels of GnRH in the hypothalamus, FSH in the pituitary and E2 in the ovary of birds fed sufficient-energy diet were higher than the corresponding counterpart in deficient-energy diet (p<0.05), respectively. In conclusion, the study implied that dietary energy modifies laying possibly through regulating reproductive hormone secretion and gene expression in hypothalamus-pituitary-gonad axis in laying geese.

The kinetics of ethyl carbamate (EC) formation was investigated during wine storage to evaluate the potential risk of EC formation in wine. The study monitored the EC, urea and citrulline concentration at different storage temperatures and wine pH. We found that temperature and initial urea content had significant effects on EC formation. The decay of urea and citrulline fit a first-order reaction approaching equilibrium, but the pH has little effect on the content of ethyl carbamate. Based on these results, we constructed an equation to forecast the content of ethyl carbamate during wine storage.