Insects,particularly black soldier fly larvae(BSFM),Hermetia illucens,have been regarded as promising protein and lipid sources in animal feed,including fish.Digestibility is the key factor that affects nutrient utili...Insects,particularly black soldier fly larvae(BSFM),Hermetia illucens,have been regarded as promising protein and lipid sources in animal feed,including fish.Digestibility is the key factor that affects nutrient utilization,feeding physiology and efficiency.In the present work,the effect of BSFM on the digestibility of red hybrid tilapia(RHT)compared to fish meal(FM)was ultimately unveiled.A 56-day growth trial was performed with 60 RHT(~30 g)randomly distributed into six tanks and fed two experimental diets containing FM as a reference diet and BSFM as a test diet.In addition,faeces were collected to determine their chromium concentration and proximate composition.The apparent digestibility coefficient(ADC)of dry matter,crude protein and energy in the BSFM diet were observed to be significantly higher than those in the FM diet.Besides,the growth performance of fish fed with the BSFM diet exhibited significantly higher(P<0.05)weight gain,specific growth rate,protein efficiency ratio and lower feed conversion ratio than those in the FM group.This study shows that the BSFM feed was well digested by tilapia and improved its growth performance.展开更多
With the growing importance of the black soldier fly(Hermetia illucens)for both sustainable food production and waste management as well as for science,a great demand of understanding its immune system arises.Here,we ...With the growing importance of the black soldier fly(Hermetia illucens)for both sustainable food production and waste management as well as for science,a great demand of understanding its immune system arises.Here,we present the first description of the circulating larval hemocytes with special emphasis on uptake of microorganisms and distinguishing hemocyte types.With histological,zymographic,and cytometric methods and with a set of hemocyte binding lectins and antibodies,the hemocytes of H.illucens are identified as plasmatocytes,crystal cells,and putative prohemocytes.Total hemocyte counts(THC)are determined,and methods for THC determination are compared.Approximately 1100 hemocytes per microliter hemolymph are present in naive animals,while hemocyte density decreases dramatically shortly after wounding,indicating a role of hemocytes in response to wounding(and immune response in general).The determination of the relative abundance of each hemocyte type(differential hemocyte count,DHC)revealed that plasmatocytes are highly abundant,whereas prohemocytes and crystal cells make up only a small percentage of the circulating cells.Plasmatocytes are not only the most abundant but also the professional phagocytes in H.illucens.They rapidly engulf and take up bacteria both in vivo and in vitro,indicating a very potent cellular defense against invading pathogens.Larger bioparticles such as yeasts are also removed from circulation by phagocytosis,but slower than bacteria.This is the first analysis of the potent cellular immune response in the black soldier fly,and a first toolbox that helps to identify hemocyte(types)is presented.展开更多
基金Ministry of Higher Education Malaysia for the Fundamental Research Grant Scheme (FRGS/1/2019/WAB01/UM/02/3)and FP073-2019A awarded to Dr Norhidayah Mohd Taufek.
文摘Insects,particularly black soldier fly larvae(BSFM),Hermetia illucens,have been regarded as promising protein and lipid sources in animal feed,including fish.Digestibility is the key factor that affects nutrient utilization,feeding physiology and efficiency.In the present work,the effect of BSFM on the digestibility of red hybrid tilapia(RHT)compared to fish meal(FM)was ultimately unveiled.A 56-day growth trial was performed with 60 RHT(~30 g)randomly distributed into six tanks and fed two experimental diets containing FM as a reference diet and BSFM as a test diet.In addition,faeces were collected to determine their chromium concentration and proximate composition.The apparent digestibility coefficient(ADC)of dry matter,crude protein and energy in the BSFM diet were observed to be significantly higher than those in the FM diet.Besides,the growth performance of fish fed with the BSFM diet exhibited significantly higher(P<0.05)weight gain,specific growth rate,protein efficiency ratio and lower feed conversion ratio than those in the FM group.This study shows that the BSFM feed was well digested by tilapia and improved its growth performance.
基金We wish to thank Prof.Herwig Gutzeit for valuable discussions and providing antibody stocks.We would like to express our gratitude to Dr.Alexander Froschauer and Prof.Klaus Reinhardt who hosted the work in their laboratories,to Prof.Thorsten Mascher and Prof.Christian Dahmann for allowing us to use their laboratory equipment,and Dr.Diana Wolf who provided bacteria strains.We thank Dr.Uwe Töpfer for valuable discussions and assistance in microscopy,Dennis Höfling for Hermetia breeding,and Katharina Starke,Yvonne Henker and Christin Froschauer for assistance in the laboratory.We thank the two anonymous reviewers for their helpful comments that improved the quality of the manuscript significantly.
文摘With the growing importance of the black soldier fly(Hermetia illucens)for both sustainable food production and waste management as well as for science,a great demand of understanding its immune system arises.Here,we present the first description of the circulating larval hemocytes with special emphasis on uptake of microorganisms and distinguishing hemocyte types.With histological,zymographic,and cytometric methods and with a set of hemocyte binding lectins and antibodies,the hemocytes of H.illucens are identified as plasmatocytes,crystal cells,and putative prohemocytes.Total hemocyte counts(THC)are determined,and methods for THC determination are compared.Approximately 1100 hemocytes per microliter hemolymph are present in naive animals,while hemocyte density decreases dramatically shortly after wounding,indicating a role of hemocytes in response to wounding(and immune response in general).The determination of the relative abundance of each hemocyte type(differential hemocyte count,DHC)revealed that plasmatocytes are highly abundant,whereas prohemocytes and crystal cells make up only a small percentage of the circulating cells.Plasmatocytes are not only the most abundant but also the professional phagocytes in H.illucens.They rapidly engulf and take up bacteria both in vivo and in vitro,indicating a very potent cellular defense against invading pathogens.Larger bioparticles such as yeasts are also removed from circulation by phagocytosis,but slower than bacteria.This is the first analysis of the potent cellular immune response in the black soldier fly,and a first toolbox that helps to identify hemocyte(types)is presented.
