Multi-omics revealed the mechanism of feed efficiency in sheep by the combined action of the host and rumen microbiota

This study was conducted to investigate potential regulatory mechanisms of feed efficiency(FE)in sheep by linking rumen microbiota with its host by the multi-omics analysis.One hundred and ninety-eight hybrid female sheep(initial body weight=30.88±4.57 kg;4-month-old)were selected as candidate sheep.Each test sheep was fed in an individual pen for 60 days,and the residual feed intake(RFI)was calculated.The ten candidate sheep with the highest RFI were divided into the Low-FE group,and the ten with the lowest RFI were divided into the High-FE group,all selected for sample collection.The RFI,average daily gain and average daily feed intake were highly significantly different between the two experimental groups(P<0.05).Compared with Low-FE group,the insulin-like growth factor-1 and very low-density lipoprotein in serum and the propionate in rumen significantly increased in High-FE group(P<0.01),but the acetate:propionate ratio in rumen significantly decreased in High-FE group(P¼0.034).Metagenomics revealed Selenomonas ruminantium,Selenomonas sp.and Faecalibacterium prausnitzii were key bacteria,and increased abundance of the genes encoding the enzymes for cellulose degradation and production of propionate in High-FE group.The results of proteomics and section showed the rumen papilla length and expression of carbonic anhydrase and Na^(+)/K^(+)-ATPase were significantly higher in High-FE group(P<0.05).On the other hand,the acetyl-CoA content significantly increased in the liver of High-FE group(P¼0.002).The relative expression levels of insulin-like growth factor-1 and apolipoprotein A4 genes were significantly up-regulated in the liver of High-FE group(P<0.05),but relative expression level of monoacylglycerol O-acyltransferase 3 gene was significantly down-regulated(P¼0.037).These findings provide the mechanism by which the collaborative interaction between rumen microbiota fermentation and host uptake and metabolism of fermentation products impacts feed efficiency traits in sheep.

Resilient distributed economic dispatch of a cyber-power system under DoS attack

The economic dispatch problem of a smart grid under vicious denial of service(DoS)is the main focus of this paper.Taking the actual situation of power generation as a starting point,a new distributed optimization model is established which takes the environmentai pollution penalty into account.For saving the limited bandwidth,a novel distributed event-triggered scheme is proposed to keep the resilience and economy of a class of cyber-power syst ems when the communication net work is subject to malicious DoS attack.Then an improved multi-agent consensus protocol based on the gradient descent idea is designed to solve the minimization problem,and the prerequisites to minimize the system power generation cost are analyzed from the aspects of optimality and stability.Finally,the theoretical results are verified through a single-area 10-generat or unit simulation.