Holothuria Scabra Seedling Large-Scale Breeding And Study Adaptability To Ecological Factors

Holothuria acabra belongs to Echinodermata Holothuria,is an economically i-mportant marine species.In recent years,with the progress of science and technolo-gyand the improvement of living standards,the sea cucumber has great potential in drug development and the use of ingredients,the current Holothuria scabra aquac-ulture production and pick up productionhave been unable to meet market demand.In recent years,the Holothuria scabra seed breeding technology research has got more attention in domestic and foreign,but its seed breeding technology is not ma-ture enough,and its ecological factor adaptation research has not been reported so far.Therefore,this article has researched the seed breeding tec-hnology in largesc-ale and the ecological factors adaptability of the Holothuria sca-bra,the results can provide technical support on Holothuria scabra aquaculture industry,it has a high application value.The main results are as follows:1.The research on the seed breeding technology in large-scaleIn this paper,We have a systematic study on the technology of artificially ind-uced spawning and larval and juveniles breeding of Holothuria scabra through the indoor factory larval breeding facility.The sea cucumber parents were induced sp-awning in a total of seven times,the success rate of spawning is 100%.It has hat-ched 57.92 million ear-shaped larvaes and 4.344 million sea cucumber seedlings,th-e average rate of seeding is 7.5%.The research has explored a systematic breeding technology in large-scale and solved the key technical problems of low spawning success rate and low seeding rate of the Holothuria scabra.2.The study on the effects of larvae and juveniles growth and development on different dietsof Holothuria scabraWe have a experimental observation on using Six kinds of foodsto have a sin-gle feeding on the ear-shaped larvaes of Holothuria scabrar auricularia,the species of foods areIsochrysis galbana,Chaetoceros muelleri,Chlorella vulgaris and the Platymonas,aquatic yeast and Spirulina respectively.The results showed that the larvaes grew well when feeding the Isochrysis galbanaor Chaetoceros muelleri alon e,it takes 168h and 192h to form the bottle-shaped larvals.When feeding the rem-aining diets alone,the larvaes were unable to develop to the bottle-shaped larvaes.Rat tail algae powder,Sargassum powder,sea mud,juvenile and adultfodderwe-re used to carry on the fed experiment observations of Holothuria scabrarespective-ly.The results showed thatit has the best effect when fed Sargassum powder,Rat tail algae powder followed.The order of specific growth rate of body mass in all experimental groups is:Sargassum powder>Rat tail algae powder>Holothuria scabr-ajuvenile fodder>Holothuria scabraadultfodder.The group of Holothuria scabrajuven-ile feeding sea mud had a negative growth state of body mass.We used mixed diets of Rat tail algae powder and Sargassum powder,Sargass-um powder and sea mud,Sargassum powder and juvenile fodder,Sargassum powd-er and sea mud,Sargassum powder and juvenile fodder,sea mud and juveniles fod-dertofeed juveniles of Holothuria scabra,and the experimental result shows that it has the best effect when fed Sargassum powder and juvenile fodder on growth of juvenile.The specific growth rate was 5.01 ± 0.30%/d.When fed Sargassum po-wder and sea mud,the specific growth rate was 1.79 ± 0.14%/d,its the worst.The order of each specific growth rate of body weight on experimentalgroupsis:(Sargassum powder and compound fodder)>(Rat tail algae powder and compound fodder)>(Rat tail algae powder and Sargassum powder)>(Sargassum powder and s-ea mud)>(sea mud and compound fodder)>(Sargassum powder and sea mud).3.The study of salinity Adaptability on the embryos,larvaes and juveniles of Holothuria scabraWe placed the fertilized eggs into the water of different salinities to observe t-he embryonic development.The results show that when the salinity in the range of 29-38,embryos can be normal embryonic development and can hatch to ear-shap-ed larvaes,the order of embryonic development rate is:(salinity)35>32>38>29.When the salinity is below 26,embryo aborted.We put the ear-shaped larvaes in water of different salinities to have a growth and development obserationg.The results show that when the ear-shaped larvae was in the salinity range of 26-38,it can grow into bottle-shaped larvae,when salinity is 23,the larval will die when grow to big-ear-shaped larvae stage.When the sal-inity is in the range of 26-35,as the salinity increases,the rate of larval develop-ment has a accelerated trend.when the salinity reaches 38,the rate of developme-nt decreased obviously.We had a obseration on the growth of Holothuria scabra juveniles which stoc-ked in water of different salinities,and the final result is that it has a positive gr-owth rate of weight gain when put the experimental groupsin the salinity range of 26-38,which the juveniles are in the range of 26-35,as the salinity increases,the ra-te of weight gain increased 1.57±0.71%to 20.24±2.75%.But when the salinity rea-ches 38,the rate of weight gain was 12.55±0.21%.When salinity is 23,the rate of weight gain was-1.91±0.21%.According to the specific growth rate of juveniles and salinitylinear relationship,the most suitable salinity of Holothuria scabra juven-iles is 34.67.4.The study of three drugs' toxicity on Holothuria scabra juvenileNormal temperature indigestion hydrostatic test method was used.Acute toxicity of three antiparasitic,that is cypermethrin,avermectin and trichlorfon,and their jo-int toxicity onHolothuria scabra juvenile were studied.The results showed that the median lethal concentrations(LC5024h)of cypermethrin,avermectin and trichlorfon were 12.86mg L-1?17.17mg·L-1 and 429.00mg·L-1 respectively,LC5048h were 10.96 mg·L-1?13.19mg·L-1 and 128.08mg·L-1 respectively.The degree of toxicity was in the order of avermectin>cypermethrin>trichlorfon,safety and quality(SC)concentrations were2.39mg·L-1?2.34mg·L-1 and 3.42mg·L-1 respectively.