Effect Of Diets On Growth And Digestive Performance Of Artemia Parthenogenetica

In this study,the Artemia parthenogenetica cysts from Barkol and Bohai Bay origin were used as experimental materials.Firstly,the basically biological characteristics of A.parthenogenetica cysts from two producing areas were determined.Then,the newly hatched larvae were fed with powder of Spirulina or Saccharomyces cerevisiae to study the effects on the growth,survival rate and digestive enzyme activities of the A.parthenogenetica.Based on the results,the composition of the intestine bacterial community of A.parthenogenetica was initially explored,which provided a technical reference for the indoor healthy culture of brine shrimp.The biological characteristics of A.parthenogenetica cysts from Barkol and Bohai Bay were studied.The results showed that the diameters of dried cysts,hydrated cysts and decapsulated cysts of A.parthenogenetica cysts from Barkol were bigger size than those cysts from Bohai Bay.The nauplii hatched from the cysts of Barkol were larger than the individuals hatched from the cysts of Bohai Bay.The shell thickness of the cysts of Barkol was thinner than that of the cysts of Bohai Bay.Different producing areas of A.parthenogenetica from Barkol and Bohai Bay were cultured with two diets of Saccharomyces cerevisiae and powder of Spirulina.Four experimental groups were established to study the effects on the growth and survival rate of A.parthenogenetica with different diets.The results indicated that different feeding had different diet effects on A.parthenogenetica.The A.parthenogenetica group fed with powder of Spirulina kept a longer survival time than the group fed with Saccharomyces cerevisiae.The group fed with Saccharomyces cerevisiae had a rapid growth rate in the early stage of growth,while fed with powder of Spirulina had a rapid growth rate in the later stage of growth.Powder of Spirulina was benefical to the growth and survival of A.parthenogenetica,A.parthenogenetica in Barkol showed relatively good growth performance.In conclusion,different diets combinations make different growth characteristics,the powder of Spirulina is a better choice to breed A.parthenogenetica in BarkolAmylase activity,trypsase activity,lipase activity and cellulase activity of A.parthenogenetica were studied.We determined the changes of digestive enzyme activities in the four stages of A.parthenogenetica from different habitats: the nauplius stage,the metanauplius stage,the pseudo adult stage and the adult stage.It was designed to reveal changes of digestive enzymes activities in different growth stages of A.parthenogenetica and their relationship with feeding.The results displayed as follows: 1)The activities of amylase and cellulase increased firstly,a peak at the metanauplius stage then decreased in the subsequent growth stages,while the activities of trypsase and lipase were found to be increased.2)In the same origin of A.parthenogenetica,the activities of trypsase,lipase,cellulase of A.parthenogenetica fed with powder of Spirulina group were significantly higher than those fed with Saccharomyces cerevisiae group(P<0.05).In the same growth stage,the amylase activity of A.parthenogenetica fed with powder of Spirulina group was significantly lower than that of the fed with Saccharomyces cerevisiae group(P<0.05).3)In the same growth stage,the digestive enzyme activities of A.parthenogenetica from Barkol and Bohai Bay showed significant differences with the same diet(P<0.05).The findings indicated that the digestive enzyme activities of A.parthenogenetica related to the growth stage and were also affected by the diet and origin.In this experiment,considering the nutritional requirements and digestive enzyme activity characteristics of A.parthenogenetica,the best combination was to use powder of Spirulina to feed A.parthenogenetica from Barkol.The intestine bacteria is increasingly regarded as an integaral component of the host,this bacterial community plays a critical role in host health via mechanisms,including the modulation of the immune system and regulation of the dietary energy intake.In this study,in order to investigate the structure of intestine bacterial community and diversity of A.parthenogenetica from Barkol with different growth stages,we documented the changes in the intestine bacterial community in four stages of A.parthenogenetica: the nauplius stage(LB.0),the metanauplius stage(LB.1),the pseudo adult stage(LB.5)and the adult stage(LB.10)using 16 S rDNA high throughput sequencing.The results showed that the intestine bacterial community was dominated by two bacterial phyla,proteobacteria and firmicutes in all stages,bacteroidetes and actinobacteria relative abundance gradually increased.Meanwhile,at the level of class classification,bacterial members belonging to alphaproteobacteria dominated in the intestine bacterial community during the nauplius stages of A.parthenogenetica,which was the gammaproteobacteria in other developmental stages.In addition,at the level of genus classification,the relative abundance of Pseudomonas increased rapidly,whereas the relative abundance of Microbacterium was in a fluctuating state.It is indicated that the structure of intestine bacterial is obviously different at different developmental stages of A.parthenogenetica.