| In this article, the experiment was conducted to study the effect of fermented kelp in cultivation of sea cucumber,by analyzing the changes of protein content in the fermented kelp, fermented kelp as trepang feed and dietary oligochitosan impact on the survival and growth,digestive enzyme and gastrointestinal microbial community structure activity stichopus japonicus non-specific immune function to evaluate the influence of fermented kelp as stichopus japonicus feed nutrition value and its development prospects. In addition, the paper also described the conditions of the fermented kelp optimization and marine yeast screening,the specific research results are as follows:1、The best conditions of Bacillus subtilis fermented kelp are: fermentation temperature 30 ℃,fermentation time 96 h,inoculation 12%(w/v, 108 cfu/m L),the crude protein content of fermented kelp is 14.65%,and relatively crude protein content increased by 15.17%.In 36 days,the compound feed content of 30% fermented kelp was used for cultivation of sea cucumber,the feed can significantly improve the trepang specific growth rate, blood lymph lysozyme activity, total superoxide dismutase(T-SOD) and acid phosphatase(ACP) activity, protease and amylase activity(P < 0.05), but the coelom cell number, cellulose enzyme activity had no significant effect(P > 0.05).In addition, which the total number of bacteria and the relative number of Vibrio were gradually reducing,the relative number of Bacillus dropped can be found in the trepang gut.Total number of heterotrophic bacteria reduced from 3.23×106 cfu.ɡ-1 to 2.86×106 cfu.ɡ-1;Vibrio relative quantity decreased to 26.82% from 36.68%;Bacillus rose to 8.92% from 15.01%.2、Kelp was fermented by aspergillus Niger and the optimum fermentation temperature is 34 ℃, fermentation time 120 h, inoculation of 10%(w/v, 108 cfu/m L), the protein content of fermented kelp is 16.53%, relatively increased by 27.64%.During the trial period,The test of feed has notably risen sea cucumber specific growth rate, blood lymph lysozyme activity, total superoxide dismutase(T SOD) activity, acid phosphatase(ACP) activity, protease activity and amylase activity(P < 0.05), but the coelom cell number, cellulose enzyme activity had no significant effect(P > 0.05). Furthermore, fermented feed make trepang intestinal total number of heterotrophic bacteria and vibrio of total bacteria number less than the original level.Total number of heterotrophic bacteria reduced from 3.23×106 cfu.ɡ-1 to 2.76×106 cfu.ɡ-1;Vibrio relative quantity decreased to 29.12% from 36.68%.3、6 strains of yeast were isolated from natural sea water and trepang gut, the physiological and biochemical and molecular biology method carried on the appraisal, the result are: the HS-1 for Debaryomyces hansenii, HS-2 for Saccharomyces cerevisiae, H-4 red yeast for Rhodotorula mucilaginosa, H-5 for Rhodosporidium diobovatum, H-10 Hannaella sinensis, H-12 to Rhodotorula marina;the crude protein content determined by kjeldahl method.This 6 strains of bacteria biomass(g/l) and protein content(w/w) is that:HS-1:5.95,33.131%;HS-2:6.22,35.972%;H-4:4.45,44.424%;H-5:5.82,50.674%;H-10:4.65,44.381%;H-12:4.35,44.871%,And the crude protein content of H-5 is significantly higher than other strains.Kelp was fermented by Rhodosporidium diobovatum, its protein content is 14.51%, relatively increased by 11.50%.In experiment,the trepang specific growth rate, coelomic fluid lysozyme activity, total superoxide dismutase(T-SOD) activity, acid phosphatase(ACP) activity, protease activity and amylase activity is significantly increased(P < 0.05), but the blood lymphocytes in the trepang coelomic fluid quantity, cellulose enzyme activity was no significant change(P > 0.05), trepang intestinal proportion of the total amount of heterotrophic bacteria and vibrio were dropped.Total number of heterotrophic bacteria reduced from 3.23×106cfu.ɡ-1 to 2.81×106cfu.ɡ-1;Vibrio relative quantity decreased to 31.04% from 36.68%;4、It was added 0.5%, 0.75%, 1.0% and 0.75% commercial shell oligosaccharides on the basis of the trepang feed.The experimental result showed that shell oligosaccharides can significantly increase the trepang specific growth rate, the coelomic fluid lysozyme activity,, but the number of blood lymphocytes,cellulose enzyme activity had no significant influence(P > 0.05),Shell oligosaccharides have inhibitory effect on the trepang intestinal heterotrophic bacteria, vibrio and bacillus subtilis, which the vibrio and bacillus subtilis in the concentration of 0.5% and 1.0% medium can’t continue to proliferate.It was found from the detection index,which the shell oligosaccharide of biological technology content reached 0.75% in the trepang feed was the most significant Oligosaccharides feed add homemade shell shell oligosaccharide feeding effect difference with the product.In conclusion, bacillus subtilis, aspergillus Niger, Marine yeast fermented kelp and feed add shell oligosaccharide feeding trepang can promote the growth of trepang, improve immune enzyme activity and the activity of digestive enzymes, and can reduce the intestinal proportion of the total number of heterotrophic bacteria and vibrio. |
PDF Full Text Request