投喂配合饲料和冰鲜鱼对双须骨舌鱼生长性能、肠道组织结构和微生物及血清生化指标的影响OA

Osteoglossum bicirrhosum is native to the Amazon River basin in Brazil and has large silver scales and a flat side.Due to its beautiful swimming posture and dignified posture,it is loved by many aquarium enthusiasts.At present,when raising O.bicirrhosum,it is usually fed with frozen fresh fish,causing resource waste and water pollution,and long-term consumption of frozen fresh fish may cause diseases in O.bicirrhosum.Artificial compound feed has the advantages of comprehensive nutrition,high safety,low feeding cost,and low pollution to water environment.This study investigated the effects of artificial compound feed(ACF)and frozen fresh fish(FFF)on the growth performance,intestinal microbiota and serum biochemical indexes of O.bicirrhosum,the culture experiment was carried out for 70 days.The results showed as follows:1)The final body weight,specific growth rate,weight gain rate and feed conversion ratio of the ACF group were significantly lower than those of the FFF group(P<0.05).2)There was damage to the intestinal morphology of O.bicirrhosum in the ACF group.3)High-throughput sequencing of 16S rRNA genes and bioinformatics analyses in the intestinal microbiotain of O.bicirrhosum and cluster of the sample bacterial sequence data with a similarity of 0.97 showed that there were 1 262 OTUs in the two groups,652 and 533 unique OTUs in the FFF group and the ACF group respectively,with a total of 77 OTUs.4)Proteobacteria and Firmicutes are the common dominant bacteria at the phylum level.When compared to the FFF group,the ACF group reduced the relative abundance of Proteobacteria,increased the relative abundance of Firmicutes,and increased the specific fusobacteria(43％).The dominant bacteria at the genus level were Edwardsiella,Plesiomonas,Romboutsia and Clostridium_sensu_stricto_1.Compared with FFF group,the ACF group reduced the relative abundance of Edwardsiella,Plesiomonas,increased the relative abundance of Clostridium_sensu_stricto_1,and increased the specific Cetobacterium(43％).5)Compared with the FFF group,the ACF group significantly reduced the activity of serum lipase(P<0.05),but had no significant effect on the activities of catalase,superoxide dismutase,triglyceride and total protein(P>0.05).The results of this study showed that FFF was more suitable for the growth needs of O.bicirrhosum,and ACF destroyed the intestinal health of O.bicirrhosum.The research results can provide basic information for enriching the nutritional value of ACF for O.bicirrhosum and promoting healthy aquaculture.