Shrimp Litopenaeus Vannamei Research Articles

Utilizing immunostimulants and probiotics for enhancing vannamei shrimp (Litopenaeus vannamei) aquaculture activities

Vannamei shrimp is one of the important fisheries commodities in Indonesia. This is because vannamei shrimp are expensive, popularly consumed by people around the world, and can be cultured. However, vannamei aquaculture activities are still hampered by disease, less production, and lack of technology implementation. Kedung Pandan Village (Jabon, Sidoarjo, East Java) is one of the potential areas for v vannamei shrimp aquaculture which is also constrained by this issues, so many farmers have gone out of business. This community service activity aims to increase the productivity of vannamei shrimp cultivation by administering immunostimulants and probiotics. In its implementation, this community service activity collaborates with "Putri Mandiri", a group of vaname shrimp farmers in Kedung Pandan Village. This activity is carried out in the stages of preparation, implementation of activities (socialization-demonstration), and evaluation. Socialization and demonstration activities were carried out on August 9 2023 and were enthusiastically participated by residents. The results of this activity indicate that the knowledge of farmers in Kedung Pandan Village, Jabon, Sidoarjo has increased and can use immunostimulants and probiotics in vannamei shrimp farming activities.

Heat-stable spores of carotenoid-producing Bacillus marisflavi and non-pigmented Bacillus subtilis cooperatively promote growth, quality, and gut microbiota of white-leg shrimp.

We evaluated the benefits of heat-stable carotenoid-producing Bacillus marisflavi SH8 spores individually and in combination with non-pigmented Bacillus subtilis SH23 spores on growth, colour change, nutritional content, innate immunity, and gut microbiota of white-leg shrimp. White-leg shrimp (Litopenaeus vannamei; n= 30 per tank; 2 tanks per group) were provided feed without (control group) or with SH8, SH23, or mixed spores (total, 1× 106 cfu/g pellet) for 28 d. The SH8 and SH8-23 combination groups had significantly higher specific growth rates (9.6 and 11.0%), improved red-colour score (4 scores), astaxanthin concentration (1.8- and 2.3-fold), lipid contents (30 and 50%), and superoxidase dismutase activity (8.5 and 12.3%) than that of the control group. Analysis of shrimp's gut microbiome using 16S rRNA metagenome sequencing revealed increased abundance of four useful species and reduced abundance of four harmful species in the combination group than in the control group. Heat-stable Bacillus spore combination improved growth parameters, nutrient content, red-colour score, live counts, and abundance of useful bacteria in the gut of L. vannamei. This is the first study to show the benefits of combining highly heat-stable pigmented and non-pigmented Bacillus spores and their possible mechanisms in a shrimp model.

Monitoring and prediction of Aeromonas veronii dynamics via absolute quantification microbiome sequencing facilitated the development of a risk assessment tool in a shrimp farm

The outbreak of infectious bacterial diseases in aquaculture is a major concern in the industry. Among those pathogens, Aeromonas species are one of the most important bacterial pathogens of cultured animals. From May to June of 2022, an unexplained Aeromonas veronii outbreak was observed in a shrimp farm with high morbidity and mortality. To develop a risk assessment tool, the dynamics of the microbiome were monitored via absolute quantification of 16S rRNA amplicon sequencing for 18 consecutive days in a recirculating aquaculture system (RAS) for rearing water and the gut of whiteleg shrimp (Litopenaeus vannamei). A growth model was also developed for predicting the growth of Aeromonas in the shrimp gut and rearing water. The results showed that A. veronii is a dominant bacterial strain isolated from sick L. vannamei. The comparison of the bacterial community in the shrimp gut and rearing water over time showed remarkable shifts in A. veronii and probiotic Bacillus in the rearing water, with a significant decline in probiotic Bacillus. The rapid increase in A. veronii in rearing water subsequently altered A. veronii populations in the shrimp gut, with over 80% of A. veronii found on day 18. Linear regression analysis revealed a strong positive relationship between the abundance of A. veronii in the shrimp gut and the rearing water. The growth kinetic model agreed well with the observed values. Collectively, the temporal dynamics of the bacterial community in the rearing water offer valuable information for the fate of administered probiotics and pathogens. Growth kinetic models provide useful information to reduce the abundance of pathogens, which can be used as an early warning tool. These observations offer crucial insights into the dynamics of the bacterial community in shrimp and their environment, which can significantly impact shrimp health and productivity.

Identification of immune-responsive circular RNAs in shrimp (Litopenaeus vannamei) upon yellow head virus infection

Circular RNAs (circRNAs) are a subclass of non-coding RNAs (ncRNAs) formed through a process known as back-splicing. They play a crucial role in the genetic regulation of various biological processes. Currently, circRNAs have been identified as participants in the antiviral response within mammalian cells. However, circRNAs in shrimp infected with the yellow head virus (YHV) remain largely unexplored. Therefore, this study aims to identify circRNAs in the hemocytes of Litopenaeus vannamei during YHV infection. We discovered 358 differentially expressed circRNAs (DECs), with 177 of them being up-regulated and 181 down-regulated. Subsequently, eight DECs, including circ_alpha-1-inhibitor 3, circ_CDC42 small effector protein 2, circ_hemicentin 2, circ_integrin alpha V, circ_kazal-type proteinase inhibitor, circ_phenoloxidase 3, circ_related protein rab-8B, and circ_protein toll-like, were randomly selected for analysis of their expression patterns during YHV infection using qRT-PCR. Furthermore, the circRNAs' characteristics were confirmed through PCR, RNase R treatment, and Sanger sequencing, all of which were consistent with the features of circRNAs. These findings contribute to a better understanding of circRNAs’ involvement in the antiviral response in shrimp.

Identifying genes involved in the secretory physiological response to feeding in Pacific White Shrimp (Litopenaeus vannamei) using transcriptomics

The physiological response to feeding is important for production aspects that include feed utilization and growth, and the responses require the action of numerous secretory factors. However, as an important aquaculture animal, the secretory response of Pacific White Shrimp (Litopenaeus vannamei) after feeding has not been comprehensively characterized. In this study, transcriptome analysis showed that 3172 differentially expressed genes were involved in the post-feeding response, including 289 new genes not annotated in the L. vannamei reference genome. Subsequently, 715 differentially expressed secretory reference genes and 18 new differentially expressed secretory genes were obtained through the identification of signal peptides in secreted proteins. Functional classification revealed that differentially expressed secretory genes were enriched in pathways pertaining to lipid metabolism (20 genes), carbohydrate metabolism (21 genes), glycan biosynthesis and metabolism (27 genes), digestive system (40 genes), and transport and metabolism (43 genes). The 14 pathways most enriched by differentially expressed secretory genes involved 83 genes, 71 of which encoded enzymes involved in food digestion and metabolism. Specific enzymes such as lipase 3-like and NPC intracellular cholesterol transporter 1-like in lipid metabolism, alpha-amylase-like and glucosylceramidase-like in carbohydrate metabolism, and cysteine proteinase 4-like and trypsin-1-like in the digestive system were found to be differentially expressed. Furthermore, we discovered a new gene, MSTRG.2504, that participates in the digestive system and carbohydrate metabolism. The study provides valuable insights into the secretory response (especially metabolism-related enzymes) to feeding in L. vannamei, uncovering the significant roles of both known and new genes. Furthermore, this study will improve our understanding of the feeding physiology of L. vannamei and provide a reference basis for further feeding endocrine research in the future.

Effect of static magnetic field-assisted freezing at different temperatures on muscle quality of pacific white shrimp (Litopenaeus vannamei)

The effect of static magnetic field-assisted freezing (MF) at different temperatures (−35, −30, −25, and −20 °C) on the muscle quality of pacific white shrimp (Litopenaeus vannamei) was evaluated to investigate the possibility of energy saving by MF. The results showed that the −35 °C MF treatment increased the water-holding capacity of shrimp muscle, and maintained the wholeness of the microstructure compared to −35 °C immersion freezing (control group, IF). With the increase in freezing temperature in the MF treatments, the size of ice crystals gradually increased, and the sensory properties of shrimp decreased. The water-holding capacity, sensory properties, and water distribution of shrimp muscle subjected to MF at −25 °C were still no significantly different from those of the IF at −35 °C (P > 0.05). In summary, the utilization of MF enhanced the quality of frozen pacific white shrimp, which has the potential to provide energy saving benefits.

A native strain of Bacillus subtilis increases lipid accumulation and modulates expression of genes related to digestion and amino acid metabolism in Litopenaeus vannamei

In the field of shrimp aquaculture, the utilization of probiotics represents a promising avenue, due to the well-documented benefits conferred by these microorganisms. In the current study, a Bacillus subtilis strain, referred to as strain E, was isolated from the gastrointestinal tract of the shrimp Litopenaeus vannamei and subsequently identified via molecular methods and phylogeny. The probiotic potential of strain E was characterized, and its application as a feed shrimp additive was evaluated in a 45-day experiment. Several parameters were assessed, including zootechnical performance, muscle tissue proximate composition, hepatopancreas lipid concentration, and the expression of genes associated with digestion, amino acid metabolism, and antioxidant defense mechanisms in various shrimp tissues. Although no significant impact on zootechnical performance was observed, supplementation with strain E led to an increase in lipid concentration within both muscle and hepatopancreas tissues. Furthermore, a marked decrease in the expression of genes linked to digestion and amino acid metabolism was noted. These findings suggest that the addition of the B. subtilis strain E to shrimp feed may enhance nutrient absorption and modulate the expression of genes related to digestion and amino acid metabolism.

Effects of electron beam irradiation on protein oxidation and textural properties of shrimp (Litopenaeus vannamei) during refrigerated storage

Protein oxidation leads to changes in shrimp texture, which affects sensory profile and consumer acceptability. This study aimed to evaluate the impact of electron beam irradiation (EBI) on protein oxidation and textural properties of Litopenaeus vannamei during refrigerated storage. Results revealed that EBI treatment and storage increased the protein oxidation level of shrimps. Shrimps irradiated with ≥ 7 kGy exhibited remarkably higher (P < 0.05) reactive oxygen species, turbidity, and carbonyl contents, and remarkably lower (P < 0.05) Ca2+-ATPase activity, surface hydrophobicity, solubility, and total sulfhydryl contents compared to the control group (0 kGy) on the 7th day of storage. Shrimps irradiated with 3 and 5 kGy exhibited remarkably higher (P < 0.05) hardness, springiness, and chewiness compared to the control group (14.99 N, 1.26 mm, and 3.19 mJ). Collectively, suitable EBI doses of 3–5 kGy were recommended in shrimp preservation to inhibit texture softening by inducing moderate protein oxidation.

Evaluation of High Stocking Densities on the Water Quality and Growth Performance of Pacific White Shrimp Litopenaeus vannamei Reared in a Mixotrophic Biofloc Nursery System

The present study aimed to explore the effects of intensive culture densities on the water quality and growth performance of the Pacific white shrimp Litopenaeus vannamei reared in a mixotrophic biofloc system (heterotrophic/chemoautotrophic) at three stocking rates of 5,000, 4,000, and 3,000 PL/m3 (namely G5000, G4000, and G3000, respectively) for 21 days. At the end of the study, the mean values of water temperature, dissolved oxygen, dissolved oxygen saturation level, pH, oxidation-reduction potential, free carbon dioxide, alkalinity, total ammonia nitrogen (TAN), nitrite-nitrogen (NO2-N), nitrate-nitrogen, and settleable solids did not substantially differ among study groups ( p &gt; 0.05 ). In addition, the highest mean levels of TAN and NO2-N recorded were 1.27 mg/l (G4000) and 9.23 mg/l (G3000), respectively. The results of growth performance revealed that final body weight, weight gain, weekly growth rate, and specific growth rate were not affected by the studied densities ( p &gt; 0.05 ). Although no significant differences were observed ( p &gt; 0.05 ), the G3000 treatment exhibited the highest survival rate (80.66% ± 8.56%), followed by G4000 (75.05% ± 0.31%) and G5000 (71.63% ± 2.11%). However, the shrimp yield was meaningfully higher for G5000 treatment (1.72 ± 0.0.09 kg/m3, 0.69 ± 0.03 kg/m2) compared with G3000 group (1.27 ± 0.0.12 kg/m3, 0.48 ± 0.04 kg/m2) ( p &lt; 0.05 ). Our results indicate L. vannamei can be reared at intensive nursery densities of up to 5,000 PL/m3 (2,000 PL/m2) until reaching 0.5 g without significant retardation in water quality, growth, and survival.

Effect of Fly Maggot Protein as Dietary on Growth and Intestinal Microbial Community of Pacific White Shrimp Litopenaeus vannamei.

As the intensive development of aquaculture persists, the demand for fishmeal continues to grow; however, since fishery resources are limited, the price of fishmeal remains high. Therefore, there is an urgent need to develop new sources of protein. They are rich in proteins, fatty acids, amino acids, chitin, vitamins, minerals, and antibacterial substances. Maggot meal-based diet is an ideal source of high-quality animal protein and a new type of protein-based immune enhancer with good application prospects in animal husbandry and aquaculture. In the present study, we investigated the effects of three different diets containing maggot protein on the growth and intestinal microflora of Litopenaeus vannamei. The shrimp were fed either a control feed (no fly maggot protein added), FM feed (compound feed with 30% fresh fly maggot protein added), FF feed (fermented fly maggot protein), or HT feed (high-temperature pelleted fly maggot protein) for eight weeks. The results showed that fresh fly maggot protein in the feed was detrimental to shrimp growth, whereas fermented and high-temperature-pelleted fly maggot protein improved shrimp growth and survival. The effects of different fly maggot protein treatments on the intestinal microbiota of L. vannamei also varied. Fermented fly maggot protein feed and high-temperature-pelleted fly maggot protein feed increased the relative abundance of Ruegeria and Pseudomonas, which increased the abundance of beneficial bacteria and thus inhibited the growth of harmful bacteria. In contrast, fresh fly maggot proteins alter the intestinal microbiome, disrupting symbiotic relationships between bacteria, and causing invasion by Vibrio and antibiotic-resistant bacteria. These results suggest that fresh fly maggot proteins affect the composition of intestinal microorganisms, which is detrimental to the intestinal tract of L. vannamei, whereas fermented fly maggot protein feed affected the growth of L. vannamei positively by improving the composition of intestinal microorganisms.

Determination of astaxanthins contribution to the aroma characteristics and aroma‐active compounds of hot‐air‐dried shrimp products using sensory evaluation, E‐nose and GC–MS

SummaryThe study investigated the contribution of astaxanthin to the aroma characteristics and aroma‐active compounds (AACs) of dried shrimp (Litopenaeus vannamei) products. Three forms of astaxanthin (diester, monoester and free forms) were isolated from fresh shrimp. The astaxanthins were added to fresh shrimp and dried. The aroma characteristics and AACs of the dried shrimp samples were analysed using electronic nose (E‐nose), and sensory evaluation as well as gas chromatography–mass spectrometry (GC–MS). The potential correlation between sensory attributes and AACs was determined via partial‐least‐squares regression (PLSR) analysis. E‐nose and sensory evaluation of dried shrimp samples revealed a significant effect of astaxanthin on the aroma characteristics of dried shrimp, resulting in increased sensory scores of smoky, toasted, meaty and caramel aroma, while reducing fishy aroma. GC–MS analysis showed that astaxanthin had a significant effect on the concentration of AACs in shrimp products. The levels of 2,5‐dimethylpyrazine, 2‐ethyl‐3,6‐dimethylpyrazine and 2,3,5‐trimethylpyrazine, benzaldehyde, 3‐methylbutyraldehyde and 2‐nonanone were increased, while the concentration of trimethylamine was reduced. However, the effects of astaxanthin on the concentration of AACs depended on its form: the diester astaxanthin had the greatest effect, followed by monoester astaxanthin and free form. The PLSR results indicated a good correlation between most variables of sensory attributes and AACs.

Comparative Genomic Analysis of Shrimp-Pathogenic Vibrio parahaemolyticus LC and Intraspecific Strains with Emphasis on Virulent Factors of Mobile Genetic Elements.

Vibrio parahaemolyticus exhibits severe pathogenicity in humans and animals worldwide. In this study, genome sequencing and comparative analyses were conducted for in-depth characterization of the virulence factor (VF) repertoire of V. parahaemolyticus strain LC, which presented significant virulence to shrimp Litopenaeus vannamei. Strain LC, harboring two circular chromosomes and three linear plasmids, demonstrated ≥98.14% average nucleotide identities with 31 publicly available V. parahaemolyticus genomes, including 13, 11, and 7 shrimp-, human-, and non-pathogenic strains, respectively. Phylogeny analysis based on dispensable genes of pan-genome clustered 11 out of 14 shrimp-pathogenic strains and 7 out of 11 clinical strains into two distinct clades, indicating the close association between host-specific pathogenicity and accessory genes. The VFDB database revealed that 150 VFs of LC were mainly associated with the secretion system, adherence, antiphagocytosis, chemotaxis, motility, and iron uptake, whereas no homologs of the typical pathogenic genes pirA, pirB, tdh, and trh were detected. Four genes, mshB, wbfT, wbfU, and wbtI, were identified in both types of pathogenic strains but were absent in non-pathogens. Notably, a unique cluster similar to Yen-Tc, which encodes an insecticidal toxin complex, and diverse toxin-antitoxin (TA) systems, were identified on the mobile genetic elements (MGEs) of LC. Conclusively, in addition to the common VFs, various unique MGE-borne VFs, including the Yen-Tc cluster, TA components, and multiple chromosome-encoded chitinase genes, may contribute to the full spectrum of LC virulence. Moreover, V. parahaemolyticus demonstrates host-specific virulence, which potentially drives the origin and spread of pathogenic factors.

Glutathione-rich yeast hydrolysate makes the contributions to growth performance, healthy of Pacific white shrimp (Litopenaeus vannamei), and helps shrimp resist nitrite stress

Seven diets were formulated to investigate the effects of glutathione-rich yeast hydrolysate (GYH) on growth performance, antioxidant capacity, and innate immunity of Litopenaeus vannamei. Based on the control diet (28% fishmeal content, CON), six diets supplement with GYH 0% (G0), 0.3% (G0.3), 0.5% (G0.5), 0.7% (G0.7), 0.9% (G0.9) and 1.1% (G1.1) were prepared after cottonseed protein concentrate replacing fishmeal 28.5% of the CON. After the 8 weeks feeding experiment, the shrimp fed diet containing 0.5%− 0.9% GYH obtained better growth performance compared to the CON and G0 groups, as well as the significantly lower feed conversion rate (P < 0.05). The intestinal villus height of shrimp fed diet with 0.3–0.9% GYH was significantly higher than the G0 group (P < 0.05). Decreased serum malondialdehyde content and significantly increased total antioxidant capacity, reduced glutathione content, activity of glutathione peroxidase and phenoloxidase in the hepatopancreas were found in shrimp fed diet with 0.7–0.9% GYH (P < 0.05). In addition, supplement 0.5–0.9% GYH significantly upregulated the expression levels of genes igf-1, pi3k, akt, tor, s6k1, and 4ebp1 in muscle and increased the crude protein content of the whole shrimp (P < 0.05). The expression levels of genes lgbp, proPO and lzm in the hepatopancreas were significantly upregulated in shrimp fed 0.7% GYH supplement (P < 0.05). Serum CAT activity in the G0.9 group was significantly higher than that of the G0 group before and after nitrite stress (P < 0.05). The shrimp fed diet supplemented with 0.5–1.1% GYH exhibited better intestinal tissue structure compared to groups CON and G0 after nitrite stress. In conclusion, the optimum level of dietary GYH was 0.67% based on the analysis of the quadratic term fitting results of weight gain rate. The diets supplemented with appropriate GYH could contribute to the growth and health of shrimp.

Genetic Diversity and Genetic Structure among Four Selected Strains of Whiteleg Shrimp (Litopenaeus vannamei) Using SSR Markers

The whiteleg shrimp (Litopenaeus vannamei) is one of the most economically important aquaculture species in China. Genetic diversity is crucial for maintaining the gene pool of farmed shrimp. In this study, the effects of artificial selection on the genetic structure of four whiteleg shrimp strains were evaluated using microsatellite sequences. The results showed that the observed heterozygosity (Ho), expected heterozygosity (He), and the polymorphism information content (PIC) of the four selected strains ranged from 0.446 to 0.574, 0.450 to 0.566, and 0.435 to 0.509, respectively. All the selected strains maintained a moderate level of genetic diversity. Most inbreeding coefficients (Fis) in the four strains were positive but not significantly different from zero, indicating a relatively low degree of inbreeding within each strain. However, He and PIC in line 5 showed a decreasing trend from the 2017 to the 2019 generations, and Fis in line 10 showed a significant increasing trend across generations, indicating that measures must be taken to maintain the level of genetic diversity for lines 5 and 10. UPGMA cluster trees showed that the four breeding lines had apparent genetic differences, which could provide a genetic basis for studying crossbreeding between selective lines and the utilization of heterosis. This study will be useful for population genetic research and the breeding strategies of whiteleg shrimp.

Different lipid levels in the Pacific white shrimp (Litopenaeus vannamei) nursery in systems grown in super-intensive biofloc systems

High stocking densities can decrease growth, feed conversion, and depletion of the shrimp immune system, therefore lipids can serve as a highly energetic source capable of meeting the metabolic demands of cultured organisms. This work aimed to evaluate the influence of different lipid levels (50 g kg−1, 70 g kg−1, 90 g kg−1, 110 g kg−1, and 130 g kg−1 extract ether-EE) in diets of Litopenaeus vannamei post-larvae raised in super-intensive biofloc systems, on growth, antioxidant capacity, and feeding costs. The experimental period lasted 30 days and the shrimp of 0.018 ± 0.001 g (PL 20) were stored (5000 PL m-³) in 20 tanks (50 L) in quadruplicates. Significant differences in water quality were not recorded (P > 0.05). The final weight and weight gain were not affected by the different treatments; however, the lowest survival rates were found in the 110 EE and 130 EE treatments and the 50 and 70 EE treatments had the highest productivity and lowest feeding cost (P < 0.05). Furthermore, no significant differences were found in the antioxidant capacity against peroxide radicals (ACAP) and thiobarbituric acid reactive species (TBARS) results (P > 0.05), which might be related to a protective effect proportionated by the biofloc consumption. The quadratic regression for productivity indicated that dietary lipid requirements for L. vannamei nursery is 67.8 g kg−1.

Evaluation of distiller's dried grains with solubles in diets for Pacific white shrimp, Litopenaeus vannamei, reared under pond conditions

AbstractMost studies evaluating the use of distiller's dried grains with solubles (DDGS) to partially replace the use of soybean meal (SBM) in diets of shrimp Litopenaeus vannamei have been carried out under laboratory conditions, which has significant differences in terms of environmental and culture conditions with the out‐door commercial pond. This study aims to extrapolate the laboratory trials into the out‐door pond condition in order to evaluate the feasibility of incorporating DDGS at various levels (D0 (0%), D5 (5%), D10 (10%), and D 15 (15%)) to replace the use of SBM for 90‐day culture period on the growth, body composition, total hemocyte count, lysozyme activity, and organoleptic characteristics of the shrimp. Seven hundred twenty shrimp (mean initial weight 1.06 ± 0.01 g) were randomly distributed into each of 40 net pens (3 × 2 × 1 per net pen) with 10 replicates per dietary treatment. The results showed an enhancement in biomass, mean weight, and thermal growth coefficient of shrimp fed with 5 and 10% inclusion levels of DDGS. Significant reduction of FCR was also observed with the use of 5 and 10% DDGS to partially replace SBM. There were no severe changes in the total hemocyte count (THC), lysozyme activity, color, aroma, and flavor of the shrimp. However, the texture of shrimp was significantly better with the use of 10 and 15% DDGS in the diet. In summary, regarding all the factors, DDGS is a promising alternative ingredient to replace the use of SBM with 5 and 10% inclusion levels and could modulate better growth, quality, and maintain the health condition of shrimp cultured in out‐door pond conditions.

Efficacy of probiotics and biofloc system in maintenance of water quality and growth performance in shrimp Litopenaeus vannamei

Efficacy of probiotics and biofloc system in maintenance of water quality and growth performance in shrimp Litopenaeus vannamei

Characteristics of the aquatic environment as a basis for brackish water pond development in the Cilacap Regency Area

The coastal of Cilacap is a large aquaculture area for vannamei shrimp (Litopenaeus vannamei). The purpose of this study is to determine the concentration of water quality in borewell and pond as the basis for brackish water development. The research method used a descriptive method by describing the sample results compared to environmental quality standards for biota based on Government Regulation Number 22 of 2021. Sampling was carried out monthly during May-July 2022 at 3 location. Observations were made on water physico-chemical parameters (temperature, pH, salinity, dissolved oxygen, BOD, nitrite, nitrate, ammonia and phosphate). Based on the analysis, it is known that the water quality of the borewell varied, namely temperature (29.75±0.96°C), pH (7.74±0.26), salinity (15±6.42%o), DO (6.52±2.83) mg/l, BOD (2.48.±1.67) mg/l, nitrate (0.43±0.38) mg/l, nitrite (0.02±0.02) mg/l, ammonia (0.46±0.30) mg/l and phosphate (0.13±0.10) mg/l. As for the pond water quality parameters, the temperature values were (30.14±1.46°C), pH (7.94±0.22), salinity (12.22±6.02%o), DO (7.58±1.30) mg/l, BOD (26.10±24.83) mg/l, nitrate (1.86±1.30) mg/l, nitrite (0.09±0.15) mg/l, ammonia (1.07±0.30) mg/l and phosphate (0.128±0.098) mg/l. Based on Government Regulation Number 22 of 2021 it is concluded that the water conditions are still suitable for the life of aquatic biota and good enough for fishery development.

The impact of ice slurry as a medium on oxidation status and flesh quality of shrimp (Litopenaeus vannamei) during refrigeration storage.

Oxidation of lipid and protein is a major reason of flesh quality deterioration during storage. In this work, cold storage (CS) and flake ice (FI) storage, as traditional strategies for live shrimp (Litopenaeus vannamei) sedation and refrigerated storage, showed remarkable oxidation damage of lipid and protein in shrimp flesh during storage. In contrast, ice slurry (IS), with good heat exchange capacity and contactability, stunned shrimp in a sudden and thus relieved antemortem stress, which resulted in reducing the reactive oxygen species and reactive nitrogen species accumulation, and the oxidation damage risk in flesh. Additionally, IS, as a storage medium acted an oxygen barrier, further inhibited the oxidation of lipid and myofibrillar protein (MP), as revealed by the lower thiobarbituric acid reactive substances level, carbonyl (CO) derives content, total disulfide bond (S-S) content, and the higher total sulfhydryl (SH) content in shrimp flesh during storage, compared with CS and FI. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis electrophoretogram pattern of MP also suggested better preservation of myosin heavy chain, myosin light chain, actin, and tropomyosin in IS, whereas these proteins degraded in CS and FI. Consequently, IS prevented the formation of cross-linking caused by oxidation in MP, leading to improved shrimp flesh quality during refrigerated storage, as demonstrated by the better maintained hardness, springiness, and water-holding capacity compared to CS and FI.

Prevention of white impurities in vaname shrimp (Litopenaeus vannamei) using noni fruit extract (Morinda citrifolia) in semi-intensive shrimp cultivation system

White vanamae shrimp is one of the superior commodities in aquaculture. Currently, the productivity of white vanamae shrimp has not yet reached its production target. So, it is necessary to increase the amount of production on a gradual scale carried out by the community. In shrimp farming activities, disease problems are often encountered. Namely is a white stool, white feces, or White Feces Disease (WFD). The clinical symptoms that arise when shrimp are attacked by White Feces Disease (WFD) are that the shrimp's appetite decreases, the shrimp's intestines change color to white and even look empty due to lack of food intake, white feces floating on the surface of the water, and the shrimp's growth becomes abnormal. This WFD disease can be caused by poor cultivation practices, unhealthy seeds, and poor water quality, causing the emergence of disease microorganisms such as Vibrio sp bacteria. One way to treat this disease is to provide alternative medicine, noni fruit extract. This research consisted of 3 noni extract treatments and consisted of 3 replications, namely Treatment A: 10 mL/L; Treatment B: 15 mL/L; Treatment C: 20 mL/L. The noni dose is given at the specified dose once daily for one month. The survival rate of shrimp increased to 86.7%.