Effects of different protein and lipid levels on the growth performance and intestinal microflora of loach(Paramisgurnus dabryanus)

The aim of this study was to examine the effects of dietary protein and lipid levels on the growth per-formance and homeostasis of the intestinal flora in Paramisgurnus dabryanus.An 8-week 3×3 two-factorial experiment was conducted to investigate the interaction between dietary crude protein(CP:30%,35%,40%)and ether extract(EE:6%,10%,14%)on the growth rate and the intestinal microflora of P.dabryanus.A total of 2,160 fish(5.19±0.01 g)were randomly allotted to 36 aquariums each with 60 fish.Fish were fed the experimental diet twice daily.Results revealed that weight gain rate(WGR),specific growth rate(SGR),protein efficiency ratio and net protein utilization significantly increased when increasing protein levels from 30%to 40%(P<0.05).Both WGR and SGR enhanced first but reduced thereafter with maximum value at 10%lipid level as dietary lipid increased from 6%to 14%(P<0.05).Significant interactions between protein and lipid were found with feed conversion rate,lipid efficiency ratio and net lipid utilization(P<0.05).At the phylum level,Proteobacteria and Actinobacteria were the dominant bacteria;at the genus level,Burkholderia-Caballeronia-Paraburkholderia was the dominant bacteria.Fish fed the diet containing 10%lipid had a higher abundance of Proteobacteria and unclassi-fied_f_Eenterobacteriaceae than those fed the 14%lipid diet,and a higher abundance of Rhodobacter than those fed the 6%lipid diet(P<0.05).Analysis of the predicted functions showed that metabolism in the intestine of fish in the CP40EE10 group was more active than that in CP30EE14 group.Polynomial regression analysis found that a diet containing 40.87%protein and 9.88%lipid can be considered optimal for P.dabryanus.

Self-Powered Room-Temperature Ethanol Sensor Based on Brush-Shaped Triboelectric Nanogenerator

Highly sensitive ethanol sensors have been widely utilized in environmental protection,industrial monitoring,and drink-driving tests.In this work,a fully self-powered ethanol detector operating at room temperature has been developed based on a triboelectric nanogenerator(TENG).The gas-sensitive oxide semiconductor is selected as the sensory component for the ethanol detection,while the resistance change of the oxide semiconductor can well match the“linear”region of the load characteristic curve of TENG.Hence,the output signal of TENG can directly reveal the concentration change of ethanol gas.An accelerator gearbox is applied to support the operation of the TENG,and the concentration change of ethanol gas can be visualized on the Liquid Crystal Display.This fully self-powered ethanol detector has excellent durability,low fabrication cost,and high selectivity of 5 ppm.Therefore,the ethanol detector based on TENG not only provides a different approach for the gas detection but also further demonstrates the application potential of TENG for various sensory devices.