凡纳滨对虾(Litopenaeus vannamei)不同产卵频次雌虾卵巢比较代谢组学分析

为探究凡纳滨对虾(Litopenaeus vannamei)雌虾产卵频次差异的分子机制,以多次产卵和不产卵凡纳滨对虾雌虾作为研究对象,采用液相色谱与质谱联用(LC-MS)非靶向代谢组学技术对成熟发育早期和晚期的雌虾卵巢进行内源性代谢物分析。结果显示,卵巢成熟发育早期,检测到156种差异代谢物,主要包括胆固醇、雄烯二酮、磷脂酰胆碱(PC)、二十二碳六烯酸(DHA)、前列腺素E2等脂类相关代谢产物,以及精氨酸、苯丙氨酸、丝氨酸、缬氨酸、亮氨酸等氨基酸,富集在128条代谢通路中,如卵巢类固醇生成、类固醇激素生物合成、氨基酸的生物合成等途径。卵巢成熟发育晚期,检测到11种差异代谢物,主要包括左旋肉碱、睾酮、磷脂酰胆碱等,富集在10条代谢通路中,如甘油磷脂代谢和卵巢类固醇生成。结果表明,不同产卵频次雌虾卵巢差异代谢物主要集中在成熟发育的早期阶段,脂类和氨基酸代谢在卵巢成熟发育早期的速度调控中可能发挥重要作用。研究结果为凡纳滨对虾产卵频次差异的内部调控机制研究提供理论依据,同时为对虾等甲壳动物的繁殖调控技术开发提供理论支持。

基于YOLOv8模型的凡纳滨对虾(Litopenaeus vannamei)摄食强度量化及分类方法研究

为实现凡纳滨对虾(Litopenaeus vannamei)摄食强度量化及分类,克服投喂主观性,优化饲料利用率。实验采用YOLOv8模型对凡纳滨对虾进行识别和检测以及YOLOv8-segment模型对凡纳滨对虾的虾头进行分割,根据饲料区域内对虾的数量和虾头的像素面积,实现对虾摄食强度的量化,并利用Convnext模型将图像中对虾的摄食强度划分为强摄食、中摄食和低摄食3个级别。实验结果显示,迭代200次后,YOLOv8模型对饲料区域内对虾目标检测的mAP50达到了99.5%,YOLOv8-segment模型对虾头分割的mAP50达到了92.1%,展现了YOLOv8模型的强大性能。经实验验证发现,在不同摄食强度下饲料区域内对虾的数量和虾头的像素面积存在明显差异。Convnext模型对凡纳滨对虾3种摄食强度的图像分类准确率为98.8%。该方法可以客观有效地将对虾摄食强度进行量化,并将对虾的摄食强度进行分类,为实现对虾的精准投喂提供了理论基础和技术支撑。

河北省海水养殖凡纳滨对虾(Litopenaeus vannamei)养殖尾水监测对比研究

以河北省黄骅地区海水工厂化和池塘养殖凡纳滨对虾尾水为研究对象,检测这两种养殖模式下不同养殖阶段所排放的养殖尾水中化学需氧量(COD)、无机氮(DIN)及活性磷酸盐(DIP)等指标的变化,利用单因子污染指数(P i)和内梅罗综合指数(P)对养殖尾水状况进行了评价。结果表明,尾水的主要污染因子为DIN与DIP;主要污染物浓度均值工厂化养殖模式高于池塘养殖模式,且工厂化养殖尾水主要污染物均超过《河北省海水养殖尾水污染物排放标准》一级排放限值;养殖尾水主要污染物浓度均随养殖时间的延长而增加;两种模式下养殖尾水的内梅罗综合指数P值均处于严重污染状等级。

凡纳滨对虾(Litopenaeus vannamei)野生群体与养殖群体的线粒体遗传变异分析

为研究凡纳滨对虾(Litopenaeus vannamei)的母系遗传背景以及遗传特性,运用线粒体基因(mtDNA)D-loop区分子标记技术,对凡纳滨对虾野生群体与养殖群体的遗传变异进行了比较分析。结果显示:野生群体与养殖群体的碱基组成一致,A+T的含量(81.52%)明显高于C+G的含量(18.48%);野生群体的单倍型多样性(H_(d))为0.960±0.017,核苷酸多样性(π)为0.104±0.051,明显高于养殖群体的(H_(d)=0.680±0.075,π=0.060±0.029)。经分子方差分析(AMOVA)发现,种群间的遗传变异率为13.09%,群体内的遗传变异率为86.91%,野生凡纳滨对虾群体与养殖群体的遗传分化存在显著差异(F_(st)=0.131,P<0.05)。本研究结果可为凡纳滨对虾的种质资源相关研究提供理论依据。

ZResponse to selection,heritability and genetic correlations between body weight and body size in Pacific white shrimp,Litopenaeus vannamei

To quantify the response to selection, heritability and genetic correlations between weight and size ofLitopenaeus vannamei, the body weight （BW）, total length （TL）, body length （BL）, first abdominal segment depth （FASD）, third abdominal segment depth （TASD）, first abdominal segment width （FASW）, and partial carapace length （PCL） of 5-month-old parents and of offspring were measured by calculating seven body measurings of offspring produced by a nested mating design. Seventeen half-sib families and 42 full-sib families ofL. vannamei were produced using artificial fertilization from 2-4 dams by each sire, and measured at around five months post-metamorphosis. The results show that heritabilities among various traits were high： 0.515±0.030 for body weight and 0.394±0.030 for total length. After one generation of selection, the selection response was 10.70% for offspring growth. In the 5th month, the realized heritability for weight was 0.296 for the offspring generation. Genetic correlations between body weight and body size were highly variable. The results indicate that external morphological parameters can be applied during breeder selection for enhancing the growth without sacrificing animals for determining the body size and breed ability; and selective breeding can be improved significantly, simultaneously with increased production.

Growth and Feed Efficiency of Juvenile Shrimp Litopenaeus vannamei Fed Formulated Diets Containing Different Levels of Poultry by-Product Meal

This feeding trial was conducted to evaluate the potential of poultry by-product meal (PBM) as a protein source in the culture of Litopenaeus vannamei. Seven isonitrogenous and isoenergetic diets were formulated to near to commercial diet with about 40% protein and 7.5% lipid. Fish meal was replaced by 0, 30%, 40%, 50%, 60%, 70% and 100% of PBM (diets 1-7). The diet with 100% fish meal was used as a control (diet 1). Post-larvae were reared in an indoor semi-closed re-circulating system. Each dietary treatment was tested in 4 replicate tanks (260 L) of 40 shrimp, arranged in a completely randomized design. The shrimps were hand-fed for three times a day to near-satiation (0700, 1200 and 1800) for 60 d. Percentage weight gain, survival, feed conversion ratio (FCR), protein efficiency ratio (PER) and body composition of shrimps were measured. There were no significant differences (P>0.05) in growth performance among shrimps fed diets 1-5 (0-60% fish meal replacement). However, shrimps fed diet 7 (100% fish meal replacement) had significantly lower (P<0.05) growth than those fed diets 1-5 (0-60% fish meal replacement). Shrimp fed diets 2-4 (30%-50% fish meal replacement) showed significantly higher growth than those fed diets 6 and 7 (70% and 100% fish meal replacement, respectively). Survival ranged from 94.7% to 100.0% and did not differ significantly (P>0.05) among different experimental diets. No differences in body composition were found among shrimps fed different diets. These results showed that up to 70% of fish meal protein can be replaced by PBM without adversely affecting the growth, survival, FCR, PER and body composition of Litopenaeus vannamei.

Effect of copper on the growth of shrimps Litopenaeus vannamei : water parameters and copper budget in a recirculating system

Shrimps( Litopenaeus vannamei) were intensively cultured in a recirculating aquaculture system for 98 days to investigate effects of 0.3 mg/L Cu on its performance, Cu budget, and Cu distribution. Shrimps in Cu-treated systems had greater mean final weight(11.10 vs 10.50 g), body length(107.23 vs 106.42 mm), survival rate(67.80% vs 66.40%), and yield(6.42 vs 5.99 kg/m 3), and lower feed conversion ratio(1.20 vs 1.29) than those in control systems but the differences were not significant. Vibrio numbers remained stable(10 4 –10 6 colony forming units/mL) in the rearing tanks of both control and treated systems. Total ammonium-N, nitrite-N, nitrate-N, pH, chemical oxygen demand, 5-day carbonaceous biochemical oxygen demand, and total suspended solids were similar in controls and treatments. Dissolved Cu concentration in the treated systems decreased from 0.284 to 0.089 mg/L while in the control systems it increased from 0.006 2 to 0.018 mg/L. The main sources of Cu in the treated systems were the artificially added component(75.7% of total input), shrimp feed(21.0%), water(2.06%), and shrimp biomass(1.22%). The major outputs of Cu occurred via the mechanical filter(41.7%), water renewal(15.6%), and draining of the sediment trap(15.1%). The foam fractionator removed only 0.69% of total Cu input. Harvested shrimp biomass accounted for 11.68% of Cu input. The Cu concentration of shrimps in the Cu-treated systems(30.70 mg/kg wet weight) was significantly higher than that in control systems(22.02 mg/kg). Both were below the maximum permissible concentration(50 mg/kg) for Cu in seafood for human consumption in China. Therefore, recirculating systems can be used for commercial on-growing of Litopenaeus vannamei without loss of shrimp quality, even in water polluted by 0.30 mg/L Cu. The mechanical filter is the main route for Cu removal.

Single or combined effects of dietary arabinoxylan-oligosaccharide and inulin on growth performance,gut microbiota,and immune response in Pacific white shrimp Litopenaeus vannamei

The single and synergistic effects of dietary arabinoxylan-oligosaccharide(AXOS)and inulin at different doses(2,4,and 8 mg/g diet)on survival,growth performance,gut microbiota,and immune response in Pacific white shrimp Litopenaeus vannamei were assessed.Singular application of either inulin or AXOS at doses of 4 mg/g diet showed the most stimulatory effects on the growth rate and gene expression levels of chitinase,cathepsin L,chymotrypsin,and extracellular signal-regulated kinase(ERK)in each single prebiotic feeding trial.Compared with single prebiotic treatments,simultaneous application of AXOS and inulin at 4 mg/g diet enhanced remarkably the growth parameters of shrimp and the expression of related genes(chitinase,cathepsin L,chymotrypsin,ERK,myeloid differentiation factor 88,and phenoloxidase)after 8-week feeding(P<0.05).Additionally,gut microbiota analysis indicated the dietary supplementation with combined prebiotics increased significantly the bacterial community richness and relative abundance of Bacillus Pseudomonas Bacteriovorax,and Lactobacillus,and reduced the abundance of Vibrio Rhodococcus,and Photobacterium in the digestive tract of L vannamei.Compared with the single prebiotic treatment and the control,combined prebiotics supplementation boosted notably the survival rate and expression levels of immune-related genes in shrimp infected with Vibrio alginolyticus or white spot syndrome virus.Therefore,simultaneous application of AXOS and inulin shall have a great potential of dietary supplement in the culture of L.vannamei.

Effects of Hypoxia on Dopamine Concentration and the Immune Response of White Shrimp (Litopenaeus vannamei)

Effects of hypoxia on the dopamme concentration and the immune response of White Shrimp Litopenaeus vannamei were studied. The results showed that hypoxia had significant effects on the concentration of dopamme （DA） in the haemolymph, haemocyte count, phenoloxidase activity, phagocytic activity of haemocytes and bacteriolytic and antibacterial activity in the haemolymph （P〈0.05）. The concentration of the dopamme in haemolymph reached its maximum in the 3.0 and 1.5 mgL^-1 DO groups at 12hand 6h, and then returned to normal after 24h and 12h, respectively. All munune parameters decreased with the reduction of dissolved oxygen. Total haemocyte count （THC）, the hyaline cells and semi-granular cells in the 3.0mgL^-1 DO group became stable after 12h, while granular cells did so after 24h. The THC and different haemocyte count （DHC） in the 1.5mgL^6-1 DO group became stable after 24 h. Phenoloxidase activity and bacteriolytic activity in the 3.0 and 1.5 mgL^-1 DO groups reached their stable levels after 24 h and 12h respectively, while phagocytic activity and antibacterial activity＂ became stable after 24 and 12, and 36 and 24h, respectively. It was also indicated that the changes of dopamme concentrations in haemolymph, haemocyte count and phenoloxidase activity were obviously related to the exposure ttrne under hypoxic conditions.

The Physicochemical Changes of Farm-Raised Pacific White Shrimp (<i>Litopenaeus vannamei</i>) as Influenced by Iced Storage

Farm-raised Pacific white shrimp (Litopenaeus vannamei) freshly harvested was evaluated for differences in proximal composition (moisture, ash, fat, and protein contents), water activity (aw), water retention index (WRI), pH, colour and texture of up to 12 days of iced storage. Shortly after harvest, the proximate composition of shrimp appeared comparable across the farms. With ice storage, the pH significantly increased whereas fat content slowly decreased particularly between days 3 and 9 (P P > 0.05). Expressly, the protein content of shrimp specimens gradually decreased after day 8 (P aw) of shrimp specimens exhibited inconsequential differences during iced storage. While the lightness (L*) was significantly affected from day 2 onwards, the yellowness (b*) colour was so but only between days 6 and 10 (P < 0.05). In addition, the adhesiveness and hardness textures of shrimp specimens registered peak values at day 11. Overall, the physicochemical differences in farm-raised shrimp during iced storage of this study provide valuable information for relevant stakeholders of the shrimp industry. Importantly, the data provided at this study can serve as baseline for comparison and evaluation of preservative treatments applied to shrimp.

Heritability of body weight and resistance to ammonia in the Pacific white shrimp Litopenaeus vannamei juveniles

Ammonia,toxic to aquaculture organisms,represents a potential problem in aquaculture systems,and the situation is exacerbated in closed and intensive shrimp farming operations,expecially for Litopenaeus vannamei.Assessing the potential for the genetic improvement of resistance to ammonia in L.vannamei requires knowledge of the genetic parameters of this trait.The heritability of resistance to ammonia was estimated using two descriptors in the present study:the survival time(ST) and the survival status at half lethal time(SS_(50)) for each individual under high ammonia challenge.The heritability of ST and SS_(50) were low(0.154 4±0.044 6 and 0.147 5±0.040 0,respectively),but they were both significantly different from zero(P<0.01).Moreover,these two estimates were basically the same and showed no significant differences from each other(P>0.05),suggesting that ST and SS_(50) could be used as suitable indicators for resistance to ammonia.There were also positive phenotypic and genetic correlation between resistance to ammonia and body weight,which means that resistance to ammonia can be enhanced by the improvement of husbandry practices that increase the body weight.The results from the present study suggest that the selection for higher body weight does not have any negative consequences for resistance to ammonia.In addition to quantitative genetics,tools from molecular genetics can be applied to selective breeding programs to improve the efficiency of selection for traits with low heritability.

EST-derived SNP discovery and selective pressure analysis in Pacific white shrimp(Litopenaeus vannamei)

Pacific white shrimp has become a major aquaculture and fishery species worldwide.Although a large scale EST resource has been publicly available since 2008,the data have not yet been widely used for SNP discovery or transcriptome-wide assessment of selective pressure.In this study,a set of 155 411 expressed sequence tags(ESTs) from the NCBI database were computationally analyzed and 17 225 single nucleotide polymorphisms(SNPs) were predicted,including 9 546 transitions,5 124 transversions and 2 481 indels.Among the 7 298 SNP substitutions located in functionally annotated contigs,58.4%(4 262) are non-synonymous SNPs capable of introducing amino acid mutations.Two hundred and fifty nonsynonymous SNPs in genes associated with economic traits have been identified as candidates for markers in selective breeding.Diversity estimates among the synonymous nucleotides were on average 3.49 times greater than those in non-synonymous,suggesting negative selection.Distribution of non-synonymous to synonymous substitutions(Ka/Ks) ratio ranges from 0 to 4.01,(average 0.42,median 0.26),suggesting that the majority of the affected genes are under purifying selection.Enrichment analysis identified multiple gene ontology categories under positive or negative selection.Categories involved in innate immune response and male gamete generation are rich in positively selected genes,which is similar to reports in Drosophila and primates.This work is the first transcriptome-wide assessment of selective pressure in a Penaeid shrimp species.The functionally annotated SNPs provide a valuable resource of potential molecular markers for selective breeding.

Effect of Replacing Fish Meal with Extruded Soybean Meal on Growth, Feed Utilization and Apparent Nutrient Digestibility of Juvenile White Shrimp(Litopenaeus vannamei)

Extruded soybean meal （ESBM） was evaluated as a protein source for partial replacement of fish meal （FM） in diets of juvenile Litopenaeus vannarnei. In the control diet （Diet 1）, FM protein was replaced with increasing dietary levels of ESBM （4.28%, 8.40%, 12.62%, 16.82%, and 25.26%） at 10%, 20%, 30%, 40%, and 60% levels （Diets 2 to 6, respectively）. An eight-week feeding trial was conducted on 720 juvenile shrimp （0.67 g ± 0.01 g mean initial Weight）, and nutrient digestibility of the six diets was determined. ESBM could replace 20% of FM without causing a significant reduction in growth of shrimp, but other dietary treatments strongly affected whole body composition. Crude protein content of the whole body fed Diet 6 was significantly lower than that fed Diet 2 （P〈0.05）, while crude lipid content of the whole body fed Diet 5 or 6 was significantly higher than that fed Diet 2 （P〈0,05）. Protein digestibilities of Diets 5 and 6 were significantly lower than that of Diet 1 （P〈0.05）. Digestibility of lipids ranged from 96.97% in Diet 6 to 98.34% in Diet 3, whereas dry matter digestibility decreased with increasing replacement level. This study indicates that 20% FM replacement with ESBM in the basic diet containing 40% protein and 30% FM is optimal for juvenile L. vannamei.

Effects of Size Grading on Growth and Non-Specific Immunity Factors of the Shrimp Litopenaeus vannamei Boone

The study aims to determine the effects of graded farming on growth performance and non-specific immunity factors of shrimp Litopenaeus vannamei Boone. Three size groups of shrimp, i.e., the small size group [Gs, with an average body length （BL） of （3.04 ± 0.36） cm and body weight （BW） （0.412± 0.35） g], the large group [GL, with a BL of （4.29±0.55） cm and BW of （1.098 ±0.42） g], and the ungraded group [Gm, with a BL of （3.47±0.81） cm and BW of （0.611 ±0.79） g], were reared under the same conditions for 8 wk. Growth performance and non- specific immunity factors were measured. The results showed that BW gain, biomass gain and the specific growth rate of body length （SGRL） were significantly influenced by size grading （one-way ANOVA, P 〈 0.05）. The peroxidase （POD） and antibacterial （Ua） activities of GL were lower than those of G. Superoxide dismutase （SOD） and lysozyme （U1） activities of Gm were lower than those of G. No significant difference （P = 0.121 〉 0.05） was found on phenoloxidase （PO） activity among the three size groups. Synthetically, size grading could enhance growth and rearing efficiency, and did not have a significant influence on the immunity of L. vannamei Boone. Therefore, graded fanning in L. vannamei Boone was feasible in the culture practice.

Effect of Dopamine Injection on the Hemocyte Count and Prophenoloxidase System of the White Shrimp Litopenaeus vannamei

Effects of dopamine injection on the hemocyte count, phenoloxidase activity, serine proteinase activity, proteinase in-hibitor activity and α2-macroglobulin-like activity in L. vannamei were studied. Results showed that dopamine injection resulted in a significant effect on the parameters measured (P < 0.05), while no significant difference was observed in the control group (0.85% NaCl). In the experimental groups,the hemocyte count reached the minimum in 3 h;granular and semi-granular cells became stable after 12 h and hyaline cells and the total hemocyte count became stable after 18 h. Phenoloxidase activity reached the minimum in 6 h, and then became stable after 9 h. Serine protease activity and proteinase inhibitor activity reached the minimum in 3 h, and α2-macro-globulin-like activity reached the maximum in 3 h,and all the three parameters became stable after 12 h. The results suggest that the activating mechanisms of the proPO system triggered by dopamine are different from those triggered by invasive agents or sponta-neously activated under a normal physical condition.

A Transcriptome Analysis of Neural Tissue of Litopenaeus vannamei After Acute Exposure to Alexandrium pacificum

Alexandrium pacificum(A.pacificum)is a typical paralytic shellfish poisonous dinoflagellate.Harmful algal blooms(HABs)caused by this species can bring serious environmental problems and economic losses to the aquaculture industry.In this study,transcriptome sequencing and analyses were performed on the neural tissue of Litopenaeus vannamei(L.vannamei)after acute exposure to A.pacificum disrupted solution for 72 h,and differentially expressed genes(DEGs)were identified.The results showed that,compared with the control samples,300 DEGs were identified in the experimental group,of which 194 were up-regulated,and 106 down-regulated.The gene ontology(GO)functional enrichment analysis showed that DEGs were significantly enriched in the cortical cytoskeleton organization,troponin complex,amylo-alpha-1,6-glucosidase and thymidine phosphorylase.Kyoto encyclopedia of genes and genomes(KEGG)enrichment analysis found that DEGs were mainly enriched in the oxidative phosphorylation process,intercellular tight junctions and mitophagy.The results showed that the proteoglycans,signaling pathways,and various metabolic processes that regulate cell proliferation,differentiation,and apoptosis all played an essential role in the response of L.vannamei to A.pacificum toxins.

Insight into the quality deterioration induced by microorganisms in Litopenaeus vannamei during superchilling storage

Quality deterioration induced by microbial community in Litopenaeus vannamei during superchilling storage were demonstrated in this study.In this study,6 microorganisms were identified as the biomarkers by 16S rDNA sequencing and 71 differential metabolites were identified by untargeted metabolomics.The correlation analysis between microorganisms and differential metabolites revealed that Oceanicaulis,Aliihoeflea,Prauserella,Chelativorans and Pseudoalteromonas had the potential to be the important microorganisms of deterioration of superchilled shrimp.Moreover,the spearman correlation analysis revealed that lightness value had highly significant correlation with Shewanella(P<0.01),and thiobarbituric acid content,total viable count value,total sulfhydryl content,trichloroacetic acid-soluble peptide and Ca2+-ATPase activity showed significantly correlation with Oceanicaulis,Prauserella,Chelativorans,Aliihoefl ea and Pseudoalteromonas(P<0.05).This study offers a better understanding for mechanisms behind quality degradation induced by microorganisms,which may help the quality maintaining of Pacific white shrimp during superchilling storage.

Effect of Sodium Alginate and Calcium Chloride on the Physicochemical Characteristics of Shrimp(Penaeus Vannamei)Surimi Gels

The object of this study is to investigate the effects of sodium alginate(SA)and CaCl_(2) on the physicochemical characteristics of shrimp surimi by studying gel strength,water holding capacity(WHC),as well as by texture profile analysis(TPA).In addition,the mechanism was analyzed through chemical interactions,protein secondary structure,and microstructure.The results showed that with the addition of different concentrations of SA and CaCl_(2) to the shrimp surimi,the gel quality firstly increased and then decreased with the increase of SA and CaCl_(2) concentrations.The highest values of WHC,breaking force and gel strength were obtained with the addition of 1.2%SA or 0.1%CaCl_(2).When SA and CaCl_(2) were used in concert,the group containing 1.2%SA and 0.15%CaCl_(2) had the highest gel strength with the densest three-dimensional network structure of the gel.In addition,the results of chemical interaction analyses showed that hydrogen and ionic bonds were the main chemical bonds of shrimp surimi sol,while shrimp surimi gel mainly consisted of hydrophobic and disulfide bonds.The incorporation of SA and CaCl_(2) resulted in a significant increase in hydrophobic interactions and disulfide bonding,which could effectively improve the gel properties of shrimp surimi.

Heterosis and heritability estimates for the survival of the Pacific white shrimp(Litopenaeus vannamei) under the commercial scale ponds

The aim of the present study is to detect the potential of the base population from diallel crosses of eight introduced strains of the Pacific white shrimp（Litopenaeus vannamei） for improving the yield. Heterosis and heritability were estimated for pond survival at commercial farm conditions for the base population that included 207 full-sib families from a nested mating design by artificial insemination. Among all the hybrids,the heterosis ranged from –11.37%（UA1×UA2） to 20.53%（UA3×SIN） with an average of 0.953%. The results showed that more than half of the hybrids（51.85%） have negative heterosis for survival rate, but most of the hybrids with positive heterosis have high estimates. The high proportion of negative heterosis for survival rate reminders us that the survival trait also should be considered in the crossbreeding program to avoid yield decrease. However, high positive heterosis manifested in most of the hybrids for survival indicates the usefulness of these hybrids for improving the survival to obtain higher yield by crossbreeding in this breeding program. The heritability estimate for pond survival was 0.092±0.043 when genetic groups were included in the pedigree, and it was significantly different from zero（P〈0.05）. The results from this study also indicated that significant improvement for survival is possible through selection in L. vannamei.

Effect of Shrimp(Litopenaeus vannamei) Farming Waste on the Growth, Digestion, Ammonium-Nitrogen Excretion of Sea Cucumber(Stichopus monotuberculatus)

In this study, specific growth rate(SGR), ingestion rate(IR), food conversion ratio(FCR), apparent digestion ratio(ADR) and ammonium-nitrogen excretion were determined for sea cucumber(Stichopus monotuberculatus) reared in plastic containers(70 L; 4 containers each diet treatment). Sea cucumbers were fed with five diets containing different amounts of farming waste from shrimp(Litopenaeus vannamei)(100%, 75%, 50%, 25% and 0) and a formulated compound(20% sea mud and 80% powdered algae). Sea cucumbers grew faster when they were fed with diet D(25% shrimp waste and 75% formulated compound) than those fed with other diets. Although IR value of sea cucumber fed with diet A(shrimp waste) was higher than those fed with other diets, both the lowest SGR and the highest FCR occurred in this diet group. The highest and the lowest ADR occurred in diet E(formulated compound) and diet A group, respectively, and the same to ammonium-nitrogen excretion. The contents of crude protein, crude lipid and total organic matter(TOM) in feces decreased in comparison with corresponding diets. In the feces from different diet treatments, the contents of crude protein and TOM increased gradually as the contents of crude protein and TOM in diets increased, while crude lipid content decreased gradually as the crude lipid content in diets increased.