A Study On The Effects Of Benthic Diatoms On Growth, Energy Budget And Physiological Function Of Apostichopus Japonicus

In this paper, we studied three different benthic diatoms. By the means of feedingApostichopus japonicus, we studied on effects of benthic diatoms on ingestion, abso-rption, energy distribution of. A. japonicus.This paper record: The oxygen consum-ption rate and ammonia excretion rate, growth, specific dynamic action(SDA), energybudget and physiological functions of A. japonicus that feeding different benthicdiatoms. This could provide basic reference for the development of the sea cucumberfeed.The results were as follows:1.Effects of benthic diatoms on oxygen consumption rate and ammonia excretionrate of Apostichopus japonicusThe oxygen consumption rate and ammonia excretion rate of Apostichopus japo-nicus were measured with feeding different benthic diatoms (Nitzschia pandurifo-rmis var.minor Grunow, Nitzchia sp., Cylindrotheca fusiformis) and a commercialfeed. The results showed that: the oxygen consumption rate was significantly differentin different groups (P<0.05). From the highest to the lowest, the oxygen consumptionrate was found at commercial feed, Nitzchia sp., Cylindrotheca fusiformis and Nitzs-chia panduriformis var. minor Grunow group respectively. The corresponding valuewas0.0259,0.02536,0.02446and0.0219mg/g·h. The ammonia excretion rate ofdifferent groups was significantly different in different groups (P<0.05). From thehighest to the lowest, the ammonia excretion rate was found at Nitzschia pandur-iformis var. minor Grunow, commercial feed, Nitzchia sp. and Cylindrotheca fusifo-rmis group respectively. The corresponding value of different groups is3.82,3.03,2.13and1.52μg/g·h.2.Effects of benthic diatoms on Specific Dynamic Action (SDA)of Apostichopusjaponicus Specific Dynamic Action (SDA) of A. japonicus was measured with feeding different benthicdiatoms (Nitzschia panduriformis var.minor Grunow, Nitzchia sp., Cylindrotheca fusiformis) and acommercial feed. The results showed that SDA was significantly different in different groups(P<0.05). The SDA duration and the metabolic rate were found at commercial feed, Nitzchia sp.,Cylindrotheca fusiformis and Nitzschia panduriformis var. minor Grunow treatment respecttively.There was no significant difference in different groups (P<0.05). The peak Vo2of A. japonicusfeed with Nitzschia panduriformis var minor Grunow、Nitzchia sp.、Cylindrotheca fusiformis anda commercial feed were27±1.2、30±1.7、29±2.1and32±1.2(mgO2kg-1·h-1), and the value ofNitzschia panduriformis var.minor Grunow were significantly lower than those of others(P<0.05). The meal size of A. japonicus feed with Nitzschia panduriformis var.minor Grunow、Nitzchia sp.、Cylindrotheca fusiformis and a commercial feed were3.38±0.12、3.75±0.25、2.16±0.11and6.37±0.19%； The energy expended on SDA of A. japonicus feed with Nitzschiapanduriformis var.minor Grunow、Nitzchia sp.、Cylindrotheca fusiformis and a commercial feedwere1.43±0.15、2.19±0.19、1.94±0.21and2.35±0.22.SDA coefficients of Nitzschia panduriformisvar.minor Grunow、Nitzchia sp.、Cylindrotheca fusiformis and a commercial feed were0.03±0.01、0.04±0.01、0.06±0.01and0.05±0.01, and the coefficient of A. japonicus fed with Nitzschiapanduriformis var.minor Grunow was significantly lower than Cylindrotheca fusiformis.3.Effects of benthic diatoms on growth and energy budget of ApostichopusjaponicusThe growth and energy budget of A. japonicus were measured with feedingdifferent benthic diatoms (Nitzschia panduriformis var.minor Grunow),(Nitzchia sp.),(Cylindrotheca fusiformis)) and a commercial feed. The results showed that thehighest survival rate of A. japonicus were measured with feeding different benthicdiatoms (Nitzschia panduriformis var.minor Grunow, Nitzchia sp., Cylindrothecafusiformis,Nitzschia panduriformis var.minor Grunow+Nitzchia sp., Nitzchia sp.+Cylindrotheca fusiformis, Nitzschia panduriformis var.minor Grunow+Nitzchia sp.+Cylindrotheca fusiformis) is91.36±5.32%, appeared in (Nitzschia panduriformisvar.minor Grunow. The highest SGR appeared in Nitzschia pandu-r iformis var.minorGrunow+Nitzchia sp.+Cylindrotheca fusiformis, The value is2.231±0.13%d-1，TheSGR of Apostichopus japonicus fed with Nitzschia panduriformis var.minor Grunow+ Nitzchia sp.+Cylindrotheca fusiformis) was higher than others（P<0.05）. The lowestDry/Wet appeared in commercial feed.The dry/wet of commercial feed was lowerthan others（P<0.05）. In the process of energy distribution mode, the energy lost infeces and respiration accounted for majority of energy intake, The maximum andGrowth Energy/Food Consumption Energy (G/C) was appeared in Nitzschia pandu-riformis var.minor Grunow+Nitzchia sp.+Cylindrotheca fusiformis.The value is3.293±0.256%, It was higher than others （P<0.05）. The minum G/C was appearedin Cylindrotheca fusiformis.The value is1.369±0.112%, It was lower than others（P<0.05）. The maximum and minxum Faecal Energy/Food Consumption Energy(F/C) was appeared in Nitzschia panduriformis var.minor Grunow and Cylindrothecafusiformis, The values are58.791±3.942%,44.523±3.171%, respecttively. There aresignificant difference between Cylindrotheca fusiformis and Nitzschia panduriformisvar.minor Grunow.4.Effects of benthic diatoms and temperature on Physiological functions of Apos-tichopus japonicusApostichopus japonicus was cultured under the temperature of15、18、21、24℃，fed with Nitzschia panduriformis var.minor Grunow、Nitzchia sp.、Cylindrotheca fusif-ormis and a commercial feed. All the benthic diatoms mix with sea mud at1:7wei-ght.The result showed that: The effect of different benthic diatoms on growth andPhysiological functions of A. japonicus is significantly different. Food intake (FI) andSGR were higher in15℃or21℃than24℃（P<0.05）. The highest SGR and FIappeared in Nitzschia panduriformis var.minor Grunow group. There was no signify-cant difference between commercial feed and Cylindrotheca fusiformis at SGR and FI（P>0.05）. As the temperature increases, the SOD, CAT, ACP activity increase, too.The highest SOD activity appeared in Nitzschia panduriformis var.minor Grunowof24℃，when experiment beginning20days, At the end of the experiment, there wasno significant difference. when Apostichopus japonicus was cultured under the tempe-rature of21℃，60days later，the CAT activity of Nitzschia panduriformis var.minorGrunow group is siginificantly higher than others, there was no significant differenceamong all groups at24℃. At the end of the experiment, all the groups are not significantly different at21℃or24℃。...