BackgroundDue to interactions with variety of environmental and physicochemical factors, the composition and diversity of bacteria and fungi in manure ectopic fermentation are constantly changing. The purpose of this study was to investigated bacterial and fungal changes in dairy manure ectopic fermentation, as well as the relationships between keystone species and physicochemical characteristics.MethodsEctopic fermentation was carried out for 93 days using mattress materials, which was combined with rice husk and rice chaff (6:4, v/v), and dairy waste mixed with manure and sewage. Physicochemical characteristics (moisture content, pH, NH4+-N (NN), total organic carbon (TO), total nitrogen (TN) and the C/N ratio) of ectopic fermentation samples were measured, as well as enzymatic activity (cellulose, urease, dehydrogenase and alkaline phosphatase). Furthermore, the bacterial and fungal communities were studied using 16S rRNA and 18S rRNA gene sequencing, as well as network properties and keystone species were analyzed.ResultsDuring the ectopic fermentation, the main pathogenic bacteria reduced while fecal coliform increased. The C/N ratio gradually decreased, whereas cellulase and dehydrogenase remained at lower levels beyond day 65, indicating fermentation maturity and stability. During fermentation, the dominant phyla were Chloroflexi, Firmicutes, Proteobacteria, Bacteroidetes, and Actinobacteria of bacteria, and Ascomycota of fungi, while bacterial and fungal community diversity changed dramatically and inversely. The association between physicochemical characteristics and community keystone taxon was examined, and C/N ratio was negative associated to keystone genus.ConclusionThese data indicated that microbial composition and diversity interacted with fermentation environment and parameters, while regulation of keystone species management of physicochemical factors might lead to improved maturation rate and quality during dairy manure ectopic fermentation. These findings provide a reference to enhance the quality and efficiency of waste management on dairy farm.

The livestock manure nitrogen load on farmland (LMNLF) is often used to assess the potential environmental pollution risk of livestock manure nitrogen nutrient (LMN) in a target region. First, the LMNLF of Wuhan city is calculated, and the potential environmental pollution risk of LMN is mainly concentrated in Jiangxia District, Xinzhou District, and Huangpi District, but does not exceed the European Union (EU) standards. Heat map results also certificate this conclusion. Therefore, these three districts are the research emphases. Second, considering spatial distribution of farms, an improved LMNLF method is proposed combining the previous LMNLF and density-based spatial clustering of applications with noise (DBSCAN) methods. Several regions with pollution risks including seven regions in Jiangxia District, one in Xinzhou District, and one in Huangpi District are found out using the improved LMNLF method. Third, to evaluate the carrying capacity of the intensive breeding areas more reasonably, 2 km is taken as the farthest transportation distance of manure; there is still one region in Huangpi District which has serious pollution risk on the environment. These above results can help evaluate the pollution degree of livestock manure to the surrounding environment more precisely.

奶牛场粪污未经处理还田或排放不仅污染环境,而且影响奶牛业的持续健康发展.以粪污的物理形态为分类依据,概述了奶牛场粪污的主要危害、处理及资源化利用技术,包括固体粪便处理技术、污水处理技术、微生物发酵床技术及处理产物的利用,简要分析了奶牛场粪污处理与资源化利用存在的主要问题及今后的发展方向,其目的在于为粪污处理与资源化利用提供参考.

Myostatin (MSTN) was previously shown to differentially regulate the adipogenesis of adipose-derived stem cells (ADSCs) and muscle satellite cells (MSCs), both of which can serve as progenitor cells for intramuscular adipocytes. We previously showed that MSTN mediates the differential regulation of MyoD and PPARγ in ADSCs and MSCs. Here, we analyzed the effects of MSTN on whole-transcriptome expression profiles of ADSCs and MSCs, revealing that MSTN differentially regulates ADSCs and MSCs, with MSCs being more responsive to MSTN treatment. More genes and pathways were altered in MSCs than in ADSCs. These changes may be responsible for the differences in the adipogenesis potential of ADSCs and MSCs after MSTN treatment. Analysis of the functions of genes that are differentially expressed in ADSCs and MSCs showed that KLF6 is a positive regulator of adipogenesis. In conclusion, the results provide important molecular insights into the regulatory mechanisms of MSTN in ADSCs and MSCs.

以武汉某公司的猪-蔬菜种养循环示范基地为研究对象,研究猪-蔬菜种养循环生态农业的生产应用.通过产品品质测定、土壤检测和水体检测,分析猪-蔬菜种养循环模式对提高蔬菜品质和产量、改善土壤质量、减少水体污染的作用.结果显示,该模式使蔬菜产量提高了30%,能显著改善土壤质量,基本没有废水排放到示范区以外,不构成水体污染.该生产模式绿色环保,具有良好的经济效益和社会效益,值得推广.