Banana Shrimp Fenneropenaeus Merguiensis Research Articles

Xenogeneic transplantation of spermatogonia from banana shrimp (Fenneropenaeus merguiensis) into white shrimp (Litopenaeus vannamei)

Banana shrimp (Fenneropenaeus merguiensis) is one of the famous shrimps for the consumer, while larvae of F. merguiensis for farming depend on wild-caught broodstock. On the other hand, white shrimp (Litopenaeus vannamei) is propagated from a culture broodstock and has a high growth rate. Currently, spermatogonia transplantation is one of the alternative methods to preserve and propagate the offspring of several vertebrates. Transplantation technology has not been reported in shrimp. This study provided information on the transplantation technique in shrimp using F. merguiensis as a donor and L. vannamei as a recipient. Spermatogonia were prepared from wild-caught F. merguiensis, 11–12 cm in length, and the cells were 8–10 µm in diameter. The spermatogonia were injected into postlarvae days 4, 9, and 16 of L. vannamei. The PKH-26 fluorescent signal was between the heart and hepatopancreas of the recipient 4 wk post-injection. In addition, the gonad of the recipient contained the proliferated donor germ cells in the gonad of the recipient after 4.5 month post-transplantation, determined by in situ hybridization with a VASA probe. The mature transplanted shrimps had dark spots on the gonad, similar to F. merguiensis's gonad. Then, the donor-derived offspring were achieved after the natural mating of transplanted shrimp. The donor-like morphology of F1 offspring was approximately 70.5%. When the genetics of F1 offspring were clarified and revealed, 2% of F. merguiensis, 28% of L. vannamei, and 70% of the hybrid between F. merguiensis and L. vannamei. The overall results indicated the successful establishment of spermatogonia transplantation in shrimp. The benefit of this work could apply to conserve or produce this shrimp in the future.

Genetic diversity and population differentiation of wild and domesticated banana shrimp Fenneropenaeus merguiensis: Applications for development of its breeding program

The basic information on genetic diversity is important for the construction of a breeding scheme leading to the sustainable farming activity of banana shrimp Fenneropenaeus merguiensis. Here, its genetic variability was examined (N = 584). Species authentication was performed by cytochrome oxidase subunit I (COI) polymorphism (N = 77). Microsatellite analysis revealed limited genetic diversity (average no. of alleles per locus, NA = 4.857-5.571) in the previous domesticated stocks. Subsequently, specimens from different geographic locations including Trat, Rayong, Chonburi, Pattani and Nakhon Si Thammarat on the Gulf of Thailand (east) and Trang and Krabi on the Andaman Sea (west) were genetically analyzed. Relatively high levels of genetic diversity (NA = 7.857–23.429) and heterozygosity (Ho = 0.500–0.733) were observed. Genetic differentiation was found between all pairwise comparisons (P < 0.001) except Trat-Nakhon Si Thammarat (P > 0.0071). Phylogenetic analysis allocated wild F. merguiensis to three groups, A (Gulf of Thailand), B (Trang) and C (Krabi). Admixture analysis did not reveal large mixing between different lineages of genotypes in each population. However, the Krabi population (west) mainly showed the eastern genetic lineage. A new domestication program was established by selecting shrimp from different genetic groups. High genetic diversity was found in founders (NA = 27.714 and AR = 14.137) and brooders of the second generation (NA = 24.571 and AR = 12.835). Currently, genome-wide association study (GWAS) of G2 shrimp exhibiting large and small sizes from four families is being carried out to analyze growth-related SNPs in this species.

Differentially expressed genes in the testes from early to mature development of banana shrimp (Fenneropenaeus merguiensis).

Banana shrimp (Fenneropenaeus merguiensis) is an economically important species in Thailand owing to the high value of globally exported frozen brine shrimps. However, the regulatory mechanisms governing spermatogenesis and testicular development in this species are poorly understood. High-throughput RNA sequencing was used to investigate the mechanisms and regulated genes involved in testis development using transcriptome profiling of juvenile and adult banana shrimp testes. Differentially expressed genes (DEGs) in these two libraries were identified and quantified to confirm gene expression. DEGs were found in 7,347 genes, with 4,465 upregulated and 2,882 downregulated. Some of these genes were designated as candidate genes, and six specific DEGs, including PRM1, SPATA20, Sry, SSRF, Sxl, and Tra-2c, were selected to confirm the reliability of the RNA-seq data using qPCR. Moreover, six non-DEGs were chosen based on testis-specific and regulatory genes that support a specific function in spermatogenesis and testis development in this species, including Dsx, Gfra2, IAG, Sox9, Sox13, and Sox14A. Furthermore, Sry, Sox14A, Sox14B and SPATA20 were identified in early stages (nauplius-postlarvae) of shrimp development to provide more information involving testes formation and development. The transcript data from this study could differentiate a group of genes required at the early and late stages of testis development and both sets of testis development. Therefore, this information would help in manipulating each stage of testicular development.

Transcriptome profiling of gonad-stimulating factors in thoracic ganglia and a potential role of Indian hedgehog gene in vitellogenesis of banana shrimp Fenneropenaeus merguiensis

Shrimp reproduction is controlled by several factors. Central nervous tissues, especially thoracic ganglia and brain, are known sources of gonad stimulating factors (GSFs) in crustaceans, but the GSFs in shrimp have not yet been clarified. Hence, we aimed to characterize and study putative GSFs from thoracic ganglia of adult female Fenneropenaeus merguiensis. An analysis of thoracic ganglia transcriptome revealed 3224 putative GSFs of a total 77,681 unigenes. Only 376 putative GSFs were differentially expressed during ovarian developmental stages. Eight candidate GSFs were validated for their expression patterns in thoracic ganglia, including the Indian hedgehog gene. F. merguiensis Indian hedgehog (FmIHH) was then investigated for its role in vitellogenesis. The obtained full-length cDNA of FmIHH was similar to other crustacean IHHs rather than Sonic and Desert HHs. The FmIHH was dominantly expressed in thoracic ganglia, and its expression was significantly increased in the vitellogenic stages before being downregulated at the mature stage of ovarian development. Injection of the recombinant FmIHH (His-TF-IHH) protein stimulated vitellogenin expression in ovaries on day 3 and 7, and also increased the gonadosomatic index. In addition, crustacean hyperglycemic hormone expression and total sugar were significantly decreased in eyestalks and hemolymph, respectively, after injection of His-TF-IHH, while lactic acid was increased. Both total sugar and lactic acid were unchanged in ovaries of His-TF-IHH injected shrimp. These results suggested that FmIHH plays a crucial role in vitellogenesis and regulate sugar uptake during ovarian development.

Histological demonstration of gonad development in the banana shrimp, Fenneropenaeus merguiensis

The genetic diversity of the banana shrimp Fenneropenaeus merguiensis is at risk because of over-harvesting, which consequently reduces food security. This endangerment is exacerbated because this species is not commonly cultivated by farmers. Overall, these factors necessitate conservation of this shrimp species across its natural habitat. Information on the migration of primordial germ cells (PGCs) to form a gonad is essential for shrimp preservation techniques such as broodstock preparation, sex differentiation, and germ cell transplantation. In this study, histological analysis and in situ hybridization of vasa expression (from embryo to testis development) were used to demonstrate the movement of PGCs. Hematoxylin and Eosin staining and in situ hybridization with the VASA probe revealed that the PGCs migrated retrogradely along the midgut, colonizing the area between the hepatopancreas and heart, a region that becomes the genital ridge in the postlarval stage. External sexual organs appeared at approximately 4 months of age. Through real-time PCR, the expression of the vasa gene was detected early on postlarval day 7, whereas its abundant expression was detected in the ovaries and testes of adult shrimp. This study could help with the identification and monitoring of PGCs or spermatogonia in banana shrimp and facilitate the implementation of other germ cell-relevant techniques in the future.

Antibiotic residue analysis of tetracycline and chloramphenicol in banana shrimp (Fenneropenaeus merguiensis) from a traditional shrimp farming in Brondong, Lamongan

Banana shrimp is one of the potential export shrimp cultivated in Brondong, Lamongan. Antibiotic residues, including pollutants, can come from cultivation pond areas and environmental pollution. The antibiotics in shrimp are tetracycline groups (oxytetracycline, chlortetracycline, and tetracycline) and chloramphenicol. This study aims to determine the presence of antibiotic residues in banana shrimp and whether the quality of the shrimp has met health safety standards based on antibiotic residue analysis using estimated daily intake (EDI) and hazard quotient (HQ) calculations. Examination of antibiotic residues is carried out at the UPT. Quality Testing and Development of Marine and Fisheries Products in Surabaya. This study used an observation method by taking shrimp samples, measuring pond water quality parameters, and testing the content of antibiotic residues in the laboratory. The examination results showed that residues of the tetracycline and chloramphenicol groups were not detected in banana shrimp. Calculations of EDI and HQ cannot be performed because antibiotic residues are not detected. The HQ value is below one, which indicates a low-risk level category. Banana shrimp from a farming pond in Brondong, Lamongan is safe for human consumption.

The effects of different stocking densities on nursery performance of Banana shrimp (Fenneropenaeus merguiensis) reared under biofloc condition

Abstract The effects of banana shrimp Fenneropenaeus merguiensis stocking density on water quality, growth performance, survival rate and body composition was assessed in a biofloc system with limited water exchange. The study was conducted for 32 days with an average larvae weight of 10 ± 0.85 mg in fiberglass tanks containing 120 L of water at four stocking densities. Five experimental treatments consisted of a control (density 1000 shrimps/ m3) with 50% daily water exchange and four biofloc treatments with limited water exchange (0.5% daily) at four stocking levels (1000 shrimps, T1; 2000 shrimps, T2, 3000 shrimps, T3 and 4000 shrimps, T4/ m3) were considered. According to the results, total ammonia nitrogen (0.99 mg/L) and nitrite levels showed higher amounts in the control compared with the other treatments (P&lt;0.05). Growth performance and survival rate (95.55%) in the biofloc treatment with a density of 1000 shrimps/ m3 were higher than the other treatments (P&lt;0.05). The proximate composition of shrimp body and biofloc produced in rearing tanks depended on the stocking density, so the shrimp body ash increased along with the enhancement of stocking density. The lowest amount of ash (31.53± 0.81%) and protein (26.38 ± 1.26) of bioflocs was observed in T1 treatment. The present study showed that stocking density affects the water quality, growth performance, survival rate and body composition of banana shrimp larvae in a biofloc system. More improved indices of water quality, growth performance and survival rate were observed with the least stocking density of 1000 shrimps/m3 in the limited water exchange system.

Biofloc as a Food Source for Banana Shrimp Fenneropenaeus merguiensis Postlarvae

AbstractThe aim of this study was to investigate the effect of different levels of wet biofloc on water quality and feeding, growth performance, survival, and body composition of banana shrimp Fenneropenaeus merguiensis. The experiment consisted of the control group (feeding 100% commercial feed and 50% water exchange per day without biofloc) and four treatments in which portions of the commercial feed were replaced by wet biofloc (T2: 25%, T3: 50%, T4: 75%, and T5: 100%) with limited water exchange. Postlarvae of banana shrimp (mean ± SD weight of 4.5 ± 0.68 mg, density of 5 postlarvae/L) were experimentally held in fiberglass tanks with 170 L of seawater with salinity of 28‰ for 30 d. An acceptable range of total ammonium nitrogen and nitrite nitrogen was maintained in rearing tanks with wet biofloc throughout the experiment despite minimal water exchanges, but total ammonium nitrogen and nitrite nitrogen were significantly higher in the control group. Postlarvae fed with 25% wet biofloc had significantly higher total biomass (222.36 g) and survival (76.27%) compared with the other treatments. A comparison of banana shrimp fed with 25% or 50% wet biofloc and those fed with 100% commercial feed did not show a significant difference in body composition. The highest levels of body ash (12.7% of dry weight) were obtained in banana shrimp fed with 100% wet biofloc. In general, it was found that up to 50% of commercial feed can be replaced with wet biofloc (developed under the conditions of this study) without compromising growth performance, survival, and carcass quality of banana shrimp postlarvae.

Chilled and cryopreserved spermatophores of banana shrimp (Fenneropenaeus merguiensis): Effects of antibiotics on sperm quality and bacterial abundance

Disease prevention is a key issue in improving reproductive biotechnology for important and endangered aquatic species to minimize the risk of pathogen transmission and economic loss. This study investigated the effects of small-dose antibiotics on sperm viability and bacterial abundance in banana shrimp (Fenneropenaeus merguiensis) spermatophores during chilled storage and cryostorage. The experiment consisted of three treatments, no antibiotic (control), 0.1% penicillin-streptomycin (PS), and 0.1% penicillin-gentamycin (PG). Antibioics were added into a sperm extender containing banana shrimp spermatophores. In the chilled storage and cryopreservation trials, the most significant (P < 0.05) improvement in sperm survival was observed in 0.1% PS-treated spermatophores over a 30-day period at 2–4 °C and 6-month in a liquid nitrogen tank. Average sperm viability ranged from 46.3 ± 3.5 to 95.7 ± 0.6% and 78.8 ± 1.1 to 95.7 ± 1.0%, respectively. In the 0.1% PS-treated spermatophores, the numbers of culturable heterotrophic bacteria (CHB) fluctuated during 21-day chilled storage and decreased (P < 0.05) over 30-day storage compared to those in the control. The CHB count in cryopreserved spermatophores decreased (P < 0.05) with increasing storage time and was undetectable by day 7 of cryostorage. Pseudomonad bacteria were not observed in both chilled-stored spermatophores by 21 days post-storage and prefrozen spermatophores when 0.1% PS was incorporated into the sperm extender. The 0.1% PS treatment also inhibited the growth of culturable Vibrio in banana shrimp spermatophores during chilled storage and cryostorage. Several species of human and shrimp pathogens and spoilage bacteria, particularly Vibrio parahaemolyticus, V. metschnikovii, V. harveyi, Aeromonas media, A. sorbria, and Plesiomonas shigelloides were not found after 0.1% PS was added to the sperm extender. This study suggests that addition of 0.1% PS into the extender not only reduces the bacterial count of chilled and postthawed cryopreserved sperm of banana shrimp, but also had no adverse effect on sperm viability.

Molecular markers for differentiation of Fenneropenaeus merguiensis among Penaeus species

The banana shrimp Fenneropenaeus merguiensis is a favourite among consumers. Therefore, overfishing has occurred. Conservation of this shrimp in the wild is essential. Conservation technologies, such as broodstock selection and germ cell transplantation, require molecular markers to discriminate F. merguiensis from other shrimps. This study developed biomarkers to distinguish F. merguiensis from other cultivated shrimps: Penaeus vannamei, Penaeus monodon and Macrobrachium rosenbergii. VASA 160 was used to differentiate F. merguiensis spermatogonia from the other three shrimps. Digestion of the amplified COI (cytochrome oxidase I) fragment with XbaI could discriminate the DNA of F. merguiensis and P. monodon from P. vannamei or M. rosenbergii. In comparison, SpeI digestion of the COI fragment differentiated F. merguiensis from P. monodon. COI266 identified the DNA of F. merguiensis from that of P. vannamei, P. monodon, and the PCR of Fm-15 showed a distinct pattern in F. merguiensis. Besides, the sensitivity of the biomarkers was determined by mixing the DNA of F. merguiensis with that of P. vannamei. VASA160, COI-RFLP and COI266 had a high sensitivity of 1:1000, while Fm 15 was at 1:100. Consequently, 30 processed shrimp foods were identified using these developed markers, and these markers will help monitor these four shrimp species in the future.

Multivariate genomic prediction for commercial traits of economic importance in Banana shrimp Fenneropenaeus merguiensis

Advantages of multi-trait machine and deep learning genomic prediction models for quantitative complex traits have not been documented or very limited in aquaculture species. Thus, the present study sought to understand effects of the multi-trait single-step genomic best linear unbiased prediction (ssGBLUP), Bayesian (BayesCpi), random forest (RF) and multilayer perceptron (MLP) models on genomic prediction accuracies for traits of commercial importance in banana white shrimp (Fenneropenaeus merguiensis). Our analyses were conducted in a breeding shrimp population comprising 562 individuals (offspring of 48 parental pairs) genotyped for 9472 single nucleotide polymorphisms (SNPs) and the animals had full phenotype records for five important traits (i.e., body weight, abdominal width, tail weight, raw colour of live shrimp and resistance to hepatopancreatic parvovirus). In both univariate and multi-trait analyses, machine (RF) and deep learning (MLP) models outperformed ssGBLUP for all traits studied. However, they had similar predictive performance to BayesCpi. The benefits of the multivariate relative to univariate models were trait- and method-specific. Multi-trait BayesCpi increased the prediction accuracies for growth (weight and width), carcass (tail weight) and HPV resistance by 9.3 to 17.8%. However, the multi-trait random forest models improved the predictive power for only abdominal width (14.3%) and disease resistance to hepatopancreatic parvovirus (10.0%). When the multi-trait MLP was used, the improvements in the prediction accuracies were observed for abdominal width and raw colour (4.9 and 6.0%, respectively). There were almost no differences in the predictive power between univariate and multi-trait ssGBLUP. Among the multi-trait models used, BayesCpi outperformed other methods (ssGBLUP, RF and MLP). It is concluded that either BayesCpi or machine and deep learning-based multi-trait genomic prediction models should be employed in large-scale genetic enhancement programs for banana shrimp. These approaches show enormous potential to enhance genetic progress made in this population of banana shrimp and potentially for other aquaculture species.

Novel Allergen Discovery through Comprehensive De Novo Transcriptomic Analyses of Five Shrimp Species.

Shellfish allergy affects 2% of the world’s population and persists for life in most patients. The diagnosis of shellfish allergy, in particular shrimp, is challenging due to the similarity of allergenic proteins from other invertebrates. Despite the clinical importance of immunological cross-reactivity among shellfish species and between allergenic invertebrates such as dust mites, the underlying molecular basis is not well understood. Here we mine the complete transcriptome of five frequently consumed shrimp species to identify and compare allergens with all known allergen sources. The transcriptomes were assembled de novo, using Trinity, from raw RNA-Seq data of the whiteleg shrimp (Litopenaeus vannamei), black tiger shrimp (Penaeus monodon), banana shrimp (Fenneropenaeus merguiensis), king shrimp (Melicertus latisulcatus), and endeavour shrimp (Metapenaeus endeavouri). BLAST searching using the two major allergen databases, WHO/IUIS Allergen Nomenclature and AllergenOnline, successfully identified all seven known crustacean allergens. The analyses revealed up to 39 unreported allergens in the different shrimp species, including heat shock protein (HSP), alpha-tubulin, chymotrypsin, cyclophilin, beta-enolase, aldolase A, and glyceraldehyde-3-phosphate dehydrogenase (G3PD). Multiple sequence alignment (Clustal Omega) demonstrated high homology with allergens from other invertebrates including mites and cockroaches. This first transcriptomic analyses of allergens in a major food source provides a valuable resource for investigating shellfish allergens, comparing invertebrate allergens and future development of improved diagnostics for food allergy.

Chilled storage of banana shrimp ( Fenneropenaeus merguiensis ) spermatophores with supplementation of moringa ( Moringa oleifera Lam.) extract

This study was designed to optimize the chilled storage method for banana shrimp (Fenneropenaeus merguiensis) spermatophores and evaluate the potential of moringa (Moringa oleifera Lam.) extract on the reduction in bacterial contaminants during spermatophore preservation due to the uncertainty of the broodstock. Spermatophores were suspended in five extenders: mineral oil, Ringer's solution, phosphate buffer, calcium-free saline and 0.8% NaCl and stored at 2–4°C. During a 28-day storage, spermatophores stored in mineral oil showed the highest sperm viability (89.1%) and intact morphology with a slight formation of hardened adhesive matrices. The effect of moringa extract was investigated on chilled spermatophores. Spermatophores were suspended in mineral oil (the control) and mineral oil containing either penicillin–streptomycin (0.1%) or moringa extract (0.1 mg/ml) during a 28-day storage. Supplementation of moringa extract resulted in a significant increase (p < .05) in sperm survival, compared to the control, and a complete elimination of culturable Vibrio (Vibrio alginolyticus, Vibrio mimicus and Vibrio furnissii), Staphylococcus kloosii, Bacillus macerans, Listeria ivanovii, Corynebacterium paurometabolum and Corynebacterium bovis, in chilled spermatophores. Chilled storage of spermatophores in mineral oil containing moringa extract was a promising technique due to the inhibition of shrimp and human pathogens without the spermicidal effect on banana shrimp sperm.

Dietary seaweed (Enteromorpha) polysaccharides improves growth performance involved in regulation of immune responses, intestinal morphology and microbial community in banana shrimp Fenneropenaeus merguiensis

The present study was conducted to evaluate the effects of marine polysaccharides from seaweed Enteromorpha on growth performance, immune responses, intestinal morphology and microbial community in the banana shrimp Fenneropenaeus merguiensis. Two thousand and four hundred juvenile shrimps with an average body weight of 2.18 ± 0.06 g were fed for 42 d with diets containing different levels of Enteromorpha polysaccharides (EPS): 0 (control), 1, 2 and 3 g/kg as treatment groups, each of group was replicated three times with two hundred shrimps per replicate. Dietary supplementation of 1 g/kg EPS showed a consistent improvement in the final weight, weight gain, average daily gain rate (ADGR) and specific growth rate (SGR) (P < 0.05), while showed a decrease in the feed conversion ratio (FCR) of shrimp (P < 0.05). Besides, the total anti-oxidative capacity (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione S-transferase (GST), lysozyme (Lyz), alkaline phosphatase (ALP), and phenoloxidase (PO) activities in hemolymph were enhanced by dietary supplementation of 1 g/kg EPS (P < 0.05), while it reduced the hemolymph MDA content (P < 0.05). Shrimp fed 1 g/kg EPS supplemented diets up-regulated FmLyz, FmSOD5 and FmCLAP gene expression level of hepatopancreas and gill (P < 0.05), and also improved the intestinal FmLC2, FmLyz, FmSOD5 and FmCLAP gene expression levels (P < 0.05). In addition, shrimp fed diets containing 1 g/kg EPS increased the villus width (P < 0.05) and resulted in a higher villus surface area (P < 0.05). According to 16S rRNA sequencing results, dietary supplementation of 1 g/kg EPS tended to increase the relative abundance of Firmicutes at phylum level (P = 0.07) and decrease the relative abundance of Vibrio at genus level (P = 0.08). There was a significant positive correlation between the relative abundance of Firmicutes and mRNA expression of intestinal immune-related genes (P < 0.05). These findings revealed that dietary 1 g/kg EPS could improve growth performance, enhance nonspecific immunity and modulate intestinal function of banana shrimp F. merguiensis.

Research into the hemocyte immune response of Fenneropenaeus merguiensis under decapod iridescent virus 1 (DIV1) challenge using transcriptome analysis

The banana shrimp (Fenneropenaeus merguiensis) is a common cultural species worldwide. With the development of the shrimp farming industry, increasing number of diseases have emerged and cause huge impacts. Decapod iridescent virus 1 (DIV1) is a new virus of the family Iridoviridae isolated in China that causes very high mortality in shrimp. In this study, DIV1 and PBS were injected into two groups of shrimp, and hemocytes were collected for comparative transcriptomic analysis. We confirmed that F. merguiensis was the new host of DIV1 by nested PCR. A total of 100,759 unigenes were assembled from the control group and the DIV1 infected group, with an average length of 733.06 bp and N50 of 1136 bp. Significant hits were found in 21,465 unigenes compared to known sequences in major databases including COG (33.30%), GO (42.17%), KEGG (46.76%), KOG (61.37%), Pfam (66.90%), Swissprot (54.21%) and Nr (93.86%). A total of 1003 differentially expressed genes (DEGs) were identified, including 929 up-regulated genes and 74 down-regulated genes. Several known immune-related genes, including caspase, C-type lectin, Wnt5 and integrin, were among the differentially expressed transcripts. A total of 14,459 simple sequence repeats, including 8128 monomers, 3276 dimers, 1693 trimers, 150 quadmers, 4 pentamers and 16 hexamers, were found in the transcriptomic dataset. Our study is the first comprehensive investigation of the transcriptomic response to DIV1 infection in F. merguiensis. Collectively, these results not only provide valuable information for characterizing the immune mechanisms of the shrimp responses to DIV1 infection, they open new ways for the study of the molecular mechanisms of DIV1 infection in F. merguiensis.

Genomic prediction for disease resistance to Hepatopancreatic parvovirus and growth, carcass and quality traits in Banana shrimp Fenneropenaeus merguiensis

Conventional genetic improvement of disease resistance in aquatic animal species involves challenge tests or using qPCR to quantify viral load that is costly, time-consuming and causing biosecurity concerns. Recent developments in high throughput next generation genome sequencing platforms such as genotyping by sequencing (GBS) have opened new possibilities for improving disease traits based on DNA information. The principal aim of this study was thus to examine potential application of genomic selection to improve resistance to hepatopancreatic parvovirus (HPV) in banana shrimp Fenneropenaeus merguiensis. Specifically, we used a total of 9472 single nucleotide polymorphisms (SNPs) developed de novo from GBS platforms to assess accuracy of genomic prediction for HPV resistance and growth, carcass and quality-related traits in this white shrimp species. Our multi-locus mixed model analysis showed moderate heritabilities for HPV resistance (h2 = 0.46) and other traits studied (0.10 to 0.55). Genetic correlations of HPV titre with growth and carcass traits, estimated using SNPs markers, were negative (i.e., favourable), suggesting that selection for improved growth and carcass traits may have increased HPV resistance (i.e., reduced HPV titre). More importantly, our gBLUP model demonstrated that the accuracy of gBLUP prediction was moderate for HPV disease resistance (0.46). The genomic prediction accuracy was somewhat greater for growth and carcass related traits especially for body weight (0.76) and meat or tail weight (0.77). On the other hand, the prediction accuracy was from 0.25 to 0.41 for quality traits (raw and cooked colour and flesh streaks). Collectively, it is concluded that there are prospects to apply genomic selection in the genetic improvement for increased disease resistance, carcass and quality-related traits in this population of banana shrimp F. merguiensis.

Cryopreservation of banana shrimp (Fenneropenaeus merguiensis) spermatophores with supplementation of medicinal plant extracts: Development of a programmable controlled-rate method and a practical method

The objectives of this study were to generate the optimal cryopreservation protocols (programmable controlled-rate and practical methods) for banana shrimp (Fenneropenaeus merguiensis) spermatophores and investigate the efficacy of plant extracts (moringa, Moringa oleifera Lam and ginger, Zingiber officinale Roscoe) on sperm survival and bacterial abundance in cryostored spermatophores. Spermatophores were exposed to various cryoprotectants at different concentrations and equilibrium times prior to examining sperm viability. A minimal toxicity to banana shrimp sperm was observed in spermatophores suspended in 5% DMSO. The optimal freezing protocol using a programmable controlled-rate freezer included exposure of spermatophores in calcium-free saline (Ca–F saline) containing 5% DMSO with 20 min equilibration time, and then utilization of a one-step freezing at the rate of −2 °C min−1 from 25 °C to −80 °C and holding for 30 s before storage in a liquid nitrogen tank. Highest sperm viability of post-thawed spermatophores was obtained after thawing at 30 °C for 2 min in a water bath. Cryopreservation of F. merguiensis spermatophores using a practical method was achieved by suspending spermatophores in Ca–F saline containing 5% DMSO with equilibration time of 20 min at 25 °C and placing at 4 cm over liquid nitrogen surface (a freezing rate of about −2.5 °C min−1) prior to plunging into liquid nitrogen. In order to evaluate the efficacy of plant extracts on sperm survival and bacterial abundance of cryostored spermatophores, two freezing protocols (programmable and practical methods) with ethanolic moringa and ginger extracts (0.1 mg mL−1 each) were developed for long-term cryostorage. Moringa and ginger extracts had no detrimental effect on F. merguiensis sperm due to retaining high viable sperm without significant differences (P > 0.05) compared to the control after a 12-month cryostorage. Supplementation of moringa or ginger extract into sperm extender resulted in a reduction of bacterial abundance in cryostored spermatophores. This report, for the first time, indicates the promising potential of plant extracts as an alternative method for controlling bacterial contaminants in cryopreserved spermatophores of penaeid shrimp.

Identification of ovarian miRNAs in banana shrimp (Fenneropenaeus merguiensis) during ovarian development between non-vitellogenic and vitellogenic shrimp

Banana shrimp (Fenneropenaeus merguiensis) is one of the popular shrimp for the consumer while the shrimp farming is not well practice due to its narrow tolerant to the environmental culture that leads to the overfishing crisis. To increase in the population number, the ovarian controlling mechanism need to be identified where the small RNAs particularly microRNAs that could regulate the expression of ovarian genes involved in ovarian development and maturation. Identification of ovarian miRNAs in banana shrimp was performed using the Illumina Hiseq 4000 system. Total 22,785,700 and 23,154,313 clean tag were counted from non-vitellogenic and vitellogenic shrimp respectively with the amount of 58 novel miRNAs. Five known miRNAs including miR-6489, miR-6491, miR-6492, miR-6493 and miR-6494, which are belonging to kuruma shrimp (Marsupenaeus japonicus) were classified together with their target prediction using RNAhybrid tool. Then, the expression of these miRNAs were quantified by RT-qPCR and found higher expression in the vitellogenic stage of all miRNAs than those in the non-vitellogenic stage. Moreover, their predicted targets were confirmed for the binding activity by luciferase assay and intramuscular injection of miRNAs into the shrimp. This data provides more understanding of the roles of some miRNAs in the regulation of the closely related shrimp ovarian gene expression.

Induction of vitellogenesis by glass bottom boat in the female banana shrimp, Fenneropenaeus merguiensis de Man

In shrimp aquaculture, eyestalk ablation is the only technique that is widely used to accelerate ovarian development. Alternative methods for producing improved ovarian development in broodstock are currently being investigated. Several factors involved in the regulation of ovarian development in shrimp have been investigated. Among these factors, growth factors in the transforming growth factor beta (TGF-β) superfamily have been implicated as playing potential roles in the regulation of gonad development. In this work, a member of the TGF-β superfamily known as glass bottom boat (GBB), an ortholog of bone morphogenetic protein (BMP), was investigated to uncover its role in ovarian development in the banana shrimp Fenneropenaeus merguiensis. Full-length cDNA of FmGBB was obtained from transcriptome data. Phylogenetic analysis indicated that the sequence of FmGBB from banana shrimp was similar to those of other arthropods and vertebrate BMP 5/6/7, but was different from those of decapentaplegic proteins and vertebrate BMP 2/4. The FmGBB transcript was found to be widely expressed in shrimp tissues, and its expression in the ovary was dramatically increased in early and late vitellogenic stages during ovarian development and decreased in the mature stage, suggesting its role in vitellogenesis. To study the effects of FmGBB, a soluble recombinant mature FmGBB peptide (His-TF-rgbb) containing both monomers and homodimers was successfully expressed in Escherichia coli. The His-TF-rgbb peptide triggered oocyte proliferation in both cultured ovarian explants and in previtellogenic shrimp upon injection. Interestingly, the injection of His-TF-rgbb into previtellogenic female shrimp stimulated an increase in Vg expression in their ovaries while suppressing production of 20-hydroxyecdysone. Our results suggest the potential role of FmGBB in oocyte proliferation and vitellogenesis; this novel finding can be utilized to stimulate ovarian development in cultured shrimp.

Molecular characterization, RNA interference and recombinant protein approach to study the function of the putative Molt Inhibiting Hormone (FmMIH1) gene from the shrimp Fenneropenaeus merguiensis

The Molt Inhibiting Hormone gene and cDNA of the banana shrimp Fenneropenaeus merguiensis (FmMIH1) has been cloned and characterized. FmMIH1 possesses most of the characteristics of the eyestalk CHH/MIH/GIH family subtype-II neuropeptides. FmMIH1 open reading frame consists of 315 bp encoding for 105 amino acid residues. The mature peptide of FmMIH1 consists of 76 amino acid residues, a glycine residue at position 11 of the mature peptide and 6 cysteine residues located in the conserved position. In addition to eyestalk, high levels of FmMIH1 transcript could also be detected in the intestine. FmMIH1 transcript level is low throughout the post-molt, early to mid-intermolt and premolt. However, a sharp increase could be observed in late intermolt (C3 stage). Both alignment and phylogenetic analysis reveal that FmMIH1 is most similar to the MIH1 of other shrimps. For functional assay, RNA interference results show that a significant 2.3 days (P < 0.05) reduction in molt cycle duration could be observed in shrimp receiving dsFmMIH1 injection. Surprisingly, injection of recombinant FmMIH1 could also cause a significant reduction of the molt cycle (average 1.9 days, P < 0.05). We hypothesize that the recombinant protein is biological inactive but it competes with the endogenous MIH for carrier protein binding and consequently reduces the amount of biological MIH that could reach the targets. In conclusion, the result of this study will provide us new insight in molting/growth control in crustacean.