Clostridium autoethanogenum protein(CAP)is a new single-cell protein source originating from inactivated bacteria.An in vitro digestion experiment and an 8-wk growth experiment were conducted to evaluate the molecular...Clostridium autoethanogenum protein(CAP)is a new single-cell protein source originating from inactivated bacteria.An in vitro digestion experiment and an 8-wk growth experiment were conducted to evaluate the molecular weight distribution of the CAP hydrolysate,and the effects of dietary CAP levels on the growth performance,plasma parameters,hepatic and intestinal health,and the diversity of gutadherent microbiota of largemouth bass(Micropterus salmoides).The fish(initial body weight of 47.99±0.01 g)were fed diets where CAP gradually replaced 0%(CAP0),12.5%(CAP12.5),25%(CAP25),37.5%(CAP37.5)and 50%(CAP50)of low-temperature steam dried anchovy fish meal(LTFM)in the diet.Results showed that the content of peptides below 1,000 Da in the CAP hydrolysate(0.56 mg/mL)was higher than that of the LTFM hydrolysate(0.48 mg/mL).Dietary CAP inclusion had no negative effect on growth performance,while whole-body lipid content significantly reduced in the CAP25 and CAP50 groups(P<0.05).The plasma alanine aminotransferase activities and triglyceride concentrations in the CAP inclusion groups were significantly lower than those in the CAP0 group(P<0.05).The plasma aspartate aminotransferase activity was significantly reduced in the CAP37.5 group(P<0.05).The richness and diversity of the gut-adhesive microbiota and the proportion of Clostridium sensu stricto 12 in the CAP50 group were significantly higher than those in the CAP0 group(P<0.05).Dietary CAP inclusion inhibited inflammatory responses by down-regulating the mRNA levels of interleukin 1b(IL1b),IL10 and transforming growth factor b1(P<0.05)in the liver.The mRNA levels of acetyl-CoA carboxylase 1 were significantly down-regulated in the CAP12.5,CAP25 and CAP37.5 groups(P<0.05),while that of fatty acid synthase was significantly down-regulated in the CAP50 group(P<0.05).These results demonstrate that dietary CAP inclusion could improve the hepatic and intestinal health of largemouth bass,and can be helpful to further develop CAP as a functional feed ingredient.展开更多
This study investigated the effects of replacing fishmeal with Clostridium autoethanogenum protein(CAP)on growth,feed utilization and intestinal histology of largemouth bass(Micropterus salmoides).The control diet con...This study investigated the effects of replacing fishmeal with Clostridium autoethanogenum protein(CAP)on growth,feed utilization and intestinal histology of largemouth bass(Micropterus salmoides).The control diet contained 350 g/kg fishmeal,and then dietary fishmeal was decreased to 300 g/kg,250 g/kg,200 g/kg,150 g/kg and 100 g/kg by CAP inclusion,respectively(FM-30,FM-25,FM-20,FM-15,FM-10).The largemouth bass(110.0±1.0 g)were fed one of the six diets for 8 weeks.The groups of FM-30,FM-25 and FM-20 showed the similar weight gain(WG)and feed conversion ratio(FCR)to the control(P>0.05),while the WG of FM-10 group was decreased by 15.9%,and FCR increased by 0.12 when compared to the control(P<0.05).FM-15 and FM-10 groups had lower protein retention,lower villus height in intestine and higher serum malondialdehyde content than the control(P<0.05).The protease activity in FM-20,FM-15 and FM-10 groups was lower than that in the control(P<0.05),but no difference was observed in crude protein digestibility among groups(P>0.05).In conclusion,CAP could replace 150 g/kg fishmeal in diet(350 g/kg fishmeal)without adverse effects on growth,feed utilization and intestinal histology of largemouth bass.展开更多
基金the National Key R&D Program of China(2019YFD0900200 and 2018YFD0900400)the National Natural Science Foundation of China(32172981 and 31902382)+1 种基金the Agricultural Science and Technology Innovation Programof CAAS in China(CAAS-ASTIP-2017-FRI-08)China Postdoctoral Science Foundation(2021M703544).
文摘Clostridium autoethanogenum protein(CAP)is a new single-cell protein source originating from inactivated bacteria.An in vitro digestion experiment and an 8-wk growth experiment were conducted to evaluate the molecular weight distribution of the CAP hydrolysate,and the effects of dietary CAP levels on the growth performance,plasma parameters,hepatic and intestinal health,and the diversity of gutadherent microbiota of largemouth bass(Micropterus salmoides).The fish(initial body weight of 47.99±0.01 g)were fed diets where CAP gradually replaced 0%(CAP0),12.5%(CAP12.5),25%(CAP25),37.5%(CAP37.5)and 50%(CAP50)of low-temperature steam dried anchovy fish meal(LTFM)in the diet.Results showed that the content of peptides below 1,000 Da in the CAP hydrolysate(0.56 mg/mL)was higher than that of the LTFM hydrolysate(0.48 mg/mL).Dietary CAP inclusion had no negative effect on growth performance,while whole-body lipid content significantly reduced in the CAP25 and CAP50 groups(P<0.05).The plasma alanine aminotransferase activities and triglyceride concentrations in the CAP inclusion groups were significantly lower than those in the CAP0 group(P<0.05).The plasma aspartate aminotransferase activity was significantly reduced in the CAP37.5 group(P<0.05).The richness and diversity of the gut-adhesive microbiota and the proportion of Clostridium sensu stricto 12 in the CAP50 group were significantly higher than those in the CAP0 group(P<0.05).Dietary CAP inclusion inhibited inflammatory responses by down-regulating the mRNA levels of interleukin 1b(IL1b),IL10 and transforming growth factor b1(P<0.05)in the liver.The mRNA levels of acetyl-CoA carboxylase 1 were significantly down-regulated in the CAP12.5,CAP25 and CAP37.5 groups(P<0.05),while that of fatty acid synthase was significantly down-regulated in the CAP50 group(P<0.05).These results demonstrate that dietary CAP inclusion could improve the hepatic and intestinal health of largemouth bass,and can be helpful to further develop CAP as a functional feed ingredient.
基金This study was financially supported by the Blue Granary Project(2019YFD0900203)from the Ministry of Science and Technology of China.
文摘This study investigated the effects of replacing fishmeal with Clostridium autoethanogenum protein(CAP)on growth,feed utilization and intestinal histology of largemouth bass(Micropterus salmoides).The control diet contained 350 g/kg fishmeal,and then dietary fishmeal was decreased to 300 g/kg,250 g/kg,200 g/kg,150 g/kg and 100 g/kg by CAP inclusion,respectively(FM-30,FM-25,FM-20,FM-15,FM-10).The largemouth bass(110.0±1.0 g)were fed one of the six diets for 8 weeks.The groups of FM-30,FM-25 and FM-20 showed the similar weight gain(WG)and feed conversion ratio(FCR)to the control(P>0.05),while the WG of FM-10 group was decreased by 15.9%,and FCR increased by 0.12 when compared to the control(P<0.05).FM-15 and FM-10 groups had lower protein retention,lower villus height in intestine and higher serum malondialdehyde content than the control(P<0.05).The protease activity in FM-20,FM-15 and FM-10 groups was lower than that in the control(P<0.05),but no difference was observed in crude protein digestibility among groups(P>0.05).In conclusion,CAP could replace 150 g/kg fishmeal in diet(350 g/kg fishmeal)without adverse effects on growth,feed utilization and intestinal histology of largemouth bass.