Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “SHRIMP”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 541 records · Page 30Linked to original sources

Identification of a cross-reactive allergen (presumably tropomyosin) in shrimp, mite and insects.

A monoclonal antibody to Dermatophagoides pteronyssinus is described that cross-reacts with an IgE-binding antigen present in insects, Crustacea (e.g. shrimp) and other invertebrates. By means of sodium dodecyl sulfate-polyacrylamide gel electrophoresis, gel filtration and immunofluorescence it was shown that this monoclonal antibody presumably recognizes tropomyosin. Tropomyosin was shown to be involved in cross-reactivity between mite, shrimp and insects in shrimp-allergic patients.

Allergens↗

Penaeidins, antimicrobial peptides with chitin-binding activity, are produced and stored in shrimp granulocytes and released after microbial challenge.

Penaeidins are members of a new family of antimicrobial peptides isolated from a crustacean, which present both Gram-positive antibacterial and antifungal activities. We have studied the localization of synthesis and storage of penaeidins in the shrimp Penaeus vannamei. The distribution of penaeidin transcripts and peptides in various tissues reveals that penaeidins are constitutively synthesized and stored in the shrimp haemocytes. It was shown by immunocytochemistry, at both optical and ultrastructural levels, that the peptides are localized in granulocyte cytoplasmic granules. The expression and localization of penaeidins were further analysed in shrimp subjected to microbial challenge. We found that (1) penaeidin mRNA levels decrease in circulating haemocytes in the first 3 hours following stimulation and (2) an increase in plasma penaeidin concentration occurs after microbial challenge, together with (3) a penaeidin immunoreactivity in cuticular tissue, which can be related to the chitin-binding activity we demonstrate here for penaeidins.

Amino Acid Sequence↗

Heat-shock response and temperature resistance in the deep-sea vent shrimp Rimicaris exoculata.

The shrimp Rimicaris exoculata swarms around hydrothermal black smoker chimneys at most vent sites along the Mid-Atlantic Ridge. This species maintains close proximity to the hydrothermal fluid, where temperatures can reach 350 degrees C and steep thermal and chemical gradients are expected. We performed in vivo experiments in pressurized aquaria to determine the upper thermal limit [critical thermal maximum (CT(max))] of R. exoculata and to investigate some characteristics of the shrimp stress response to heat exposure. These experiments showed that the shrimp does not tolerate sustained exposure to temperatures in the 33-37 degrees C range (CT(max)). A heat-inducible stress protein belonging to the hsp70 family was identified in R. exoculata, and its synthesis threshold induction temperature is below 25 degrees C. The R. exoculata optimal thermal habitat may thus be restricted to values lower than previously expected (<25 degrees C).

Animals↗

Hypoxia accelerates the development of respiratory regulation in brine shrimp - but at a cost

The ability to regulate O(2) uptake during exposure to acutely declining O(2) tensions developed early (stage 6) in the brine shrimp Artemia franciscana and co-occurred with the appearance of a functional heart and gills. Culture under chronic hypoxia (P(O2)=10 kPa) resulted in this regulation being brought forward both in development (to stage 3) and in time (hypoxia stimulated early growth), but still before heart and gill formation took place. Consequently, it was suggested that the hypoxia-related early appearance of respiratory regulation is most probably linked to an increase in haemoglobin concentration that occurred at this time. Brine shrimp cultured under conditions of intermittent hypoxia exposure (16 h of normoxia, 8 h of hypoxia) showed a pattern of regulation development intermediate between that of individuals reared in normoxic and chronically hypoxic culture. This occurrence of hypoxia-related, physiological 'heterochrony' in brine shrimp resulted in a decrease in Darwinian fitness (as indicated by a decrease in individual lifetime reproductive output), indicating that, in some cases at least, relatively small alterations in the expression of physiological traits may well have major ecological, and ultimately evolutionary, consequences.

Journal Article↗

Current status of trade in cultured shrimps.

Shrimp culture is an attractive sector of aquaculture business, in view of the high profits and quick turnover. The vast majority of cultured shrimp production occurs in Asian countries. The author details the levels of production, consumption and trade of cultured shrimps since 1991 in and between the major producing countries. A decline in production has been registered in some countries in recent years, due to mass mortality caused by a number of diseases (particularly 'white spot' disease). Efforts to overcome these problems have met with only partial success.

Animals↗

Bagasse-assisted bioremediation of ammonia from shrimp farm wastewater.

Development of new economically feasible ecofriendly products from agricultural wastes or byproducts for shrimp farm wastewater treatment is the objective of our continued research. Ammonia is a nitrogenous toxicant, which is commonly found in wastewater from shrimp farms. In the present study, we explored the possibility of the use of simply and inexpensively prepared bagasse products so that this abundant crop byproduct could be used to remove ammonia from shrimp farm wastewater. Bagasse, a natural highly fibrous lignocellulosic byproduct of sugarcane, was converted into five different products. Experimental results have shown that ammonia is efficiently removed from wastewater by four bagasse products with a dose of 1 to 6 g/L within 24 hours. The effect of bagasse products on other water quality parameters and growth kinetics of biofilm bacteria onto bagasse fiber have also been studied. Efficacies of products were compared by using statistical analysis. Products developed from bagasse are useful and economical.

Ammonia↗

Parallel processing and image analysis in the eyes of mantis shrimps.

The compound eyes of mantis shrimps, a group of tropical marine crustaceans, incorporate principles of serial and parallel processing of visual information that may be applicable to artificial imaging systems. Their eyes include numerous specializations for analysis of the spectral and polarizational properties of light, and include more photoreceptor classes for analysis of ultraviolet light, color, and polarization than occur in any other known visual system. This is possible because receptors in different regions of the eye are anatomically diverse and incorporate unusual structural features, such as spectral filters, not seen in other compound eyes. Unlike eyes of most other animals, eyes of mantis shrimps must move to acquire some types of visual information and to integrate color and polarization with spatial vision. Information leaving the retina appears to be processed into numerous parallel data streams leading into the central nervous system, greatly reducing the analytical requirements at higher levels. Many of these unusual features of mantis shrimp vision may inspire new sensor designs for machine vision.

Animals↗

Signaling via water currents in behavioral interactions of snapping shrimp (Alpheus heterochaelis).

The snappping shrimp Alpheus heterochaelis produces a variety of different water currents during intraspecific encounters and interspecific interactions with small sympatric crabs (Eurypanopeus depressus). We studied the mechanisms of current production in tethered shrimp and the use of the different currents in freely behaving animals. The beating of the pleopods results in strong posteriorly directed currents. Although they reach rather far, these currents show no distinctions when directed toward different opponents. Gill currents are produced by movements of the scaphognathites (the exopodites of the second maxillae) and can then be deflected laterally by movements of the exopodites of the first and second maxillipeds. These frequent but slow lateral gill currents are most probably used to enhance chemical odor perception. The fast and focused, anteriorly directed gill currents, however, represent a powerful tool in intraspecific signaling, because they reach the chemo- and mechanosensory antennules of the opponent more often than any other currents and also because they are produced soon after previous contacts between the animals. They may carry chemical information about the social status of their producers since dominant shrimp release more anterior gill currents and more water jets than subordinate animals in intrasexual interactions.

Animals↗

Effects of hypoxia and hypercapnic hypoxia on the localization and the elimination of Vibrio campbellii in Litopenaeus vannamei, the Pacific white shrimp.

Low oxygen (hypoxia) and elevated CO2 (hypercapnia, are characteristic of estuarine environments. Although hypoxia and hypercapnic hypoxia decrease the resistance of shrimp to bacterial pathogens, their direct effects on the immune system are unknown. Here we present evidence demonstrating in the penaeid shrimp Litopenaeus vannamei that both hypoxia and hypercapnic hypoxia affect the localization of bacteria, their conversion from culturable to non-culturable status (bacteriostasis), and their elimination from hemolymph and selected tissues. Shrimp were injected with a sublethal dose of a pathogenic strain of Vibrio campbellii expressing green fluorescent protein and resistance to kanamycin. Real-time polymerase chain reaction was used to determine the number of intact V. campbellii in hemolymph, gills, hepatopancreas, heart, and lymphoid organ. Selective plating was used to quantify the injected bacteria that remained culturable. We found that both hypercapnic hypoxia and hypoxia increased the percentage of culturable bacteria recovered from the hemolymph and tissues, suggesting an overall decrease in bacteriostatic activity. Hypoxia and hypercapnic hypoxia generally increased the distribution of intact V. campbellii to the hepatopancreas and the gills, which are major targets for the pathogenic effects of Vibrio spp., without affecting the number of intact bacteria in the lymphoid organ, a main site of bacterial accumulation and bacteriostatic activity.

Animals↗

Taura syndrome of penaeid shrimp: cloning of viral genome fragments and development of specific gene probes.

The ssRNA genome extracted from purified Taura Syndrome Virus (TSV) was transcribed into double-stranded, blunt-ended cDNA and was used to construct cDNA libraries either in pUC 18 or in pBluescript II KS-vectors. Twelve recombinant plasmids chosen after screening of the libraries were subjected to restriction enzyme digestions for determination of size inserts and restriction maps. Two of them, pP15 and pQ1, were selected for probe construction. The inserts, 1500 and 1300 base pairs (bp) respectively, were DIG-11dUTP-labelled and the corresponding probes were named P15 and Q1. On northern blots and dot blots, using different denaturation methods, the 2 probes hybridized specifically with extracted RNA-TSV genome, TSV and infected TS shrimp homogenates. No positive hybridization was obtained with other shrimp viruses tested [Infectious Hypodermal and Hematopoietic Necrosis Virus (IHHNV) and Hepatopancreatic Parvovirus (HPV)]. The specificity of the 2 probes was confirmed by in situ hybridization on histological sections of TS diseased shrimps.

Animals↗

An infectious viral disease of penaeid shrimp newly found in Korea.

Since 1993, massive mortalities have occurred among the penaeid shrimp Penaeus orientalis cultured in Korea. The major gross findings of the naturally occurring cases were 2 to 6 mm sized white spots on the inside of the carapace and reddish discolorization. Amphophilic to basophilic intranuclear inclusion bodies were readily observed in the epithelia of epidermis, foregut, gills, and lymphoid organs. Electron microscopy revealed enveloped and non-occluded ellipsoid to rod-shaped virus particles within the nucleus of lymphoid organ cells and the interstitial cells of the hepatopancreas of both naturally and experimentally infected shrimp. The size of the virions was 375 x 167 nm and the nucleocapsid was 290 x 75 nm. The agent which caused ectodermal and mesodermal necrosis in penaeid shrimp in Korea resembled white spot syndrome virus (WSSV) found in Taiwan with respect to gross signs, histological changes and viral morphology. Its viral morphology differed from that of the rod-shaped nuclear virus of Penaeus japonicus (RV-PJ) found in Japan. However, a 643 bp PCR product with an identical sequence to that from RV-PJ was detected. The results suggested that the Korean agent combined characters described for WSSV and RV-PJ.

Animals↗

Different reactions obtained using the same DNA detection reagents for Thai and Korean hepatopancreatic parvovirus of penaeid shrimp.

Hepatopancreatic parvovirus (HPV) can cause stunted growth and death in penaeid shrimp including Penaeus monodon. We used PCR primers and a commercial DNA probe designed from HPV of Penaeus chinensis (HPVchin) to examine HPV-infected Thai P. monodon (HPVmon). We found that the PCR primers produced a 732 bp DNA amplicon rather than the 350 bp amplicon obtained with HPVchin template and that the DNA probe gave weak to variable in situ DNA hybridization results. In addition, hybridization to PCR products from HPVmon was weak compared with hybridization with PCR products from HPVchin. By contrast, the 732 bp amplicon hybridized strongly with HPVmon-infected cells by in situ hybridization but not with uninfected shrimp tissue or other shrimp viruses, thus confirming its origin from HPVmon. Cloning, sequencing and analysis of the 732 bp amplicon showed that 696 bp (excluding the primer sequences) contained 47% GC content and had only 78% homology to 701 aligned bases from a 3350 bp DNA fragment of HPVchin from GenBank. These results explain why the reagents based on HPVchin gave a different PCR product and weak hybridization results with HPVmon, and they show that multiple primers or degenerate primers may be necessary for general detection of HPV varieties. Together with previously published information on the estimated total genome sizes for HPVchin (approximately 4 kb) and HPVmon (approximately 6 kb), these data support the contention that HPVchin and HPVmon are different varieties or species, in spite of their similar histopathology.

Animals↗

Estimation of prevalence of white spot syndrome virus (WSSV) by polymerase chain reaction in Penaeus monodon postlarvae at time of stocking in shrimp farms of Karnataka, India: a population-based study.

White spot disease (WSD) is at present the most serious viral disease affecting cultivated shrimp species globally. The causative agent, white spot syndrome virus (WSSV), is extremely virulent, has a wide host range and can also be transmitted from broodstock to their offspring. The shrimp postlarvae (PL) act as asymptomatic, latent carriers of the virus, and stocking of WSSV-infected PL has been reported as a risk factor for WSD outbreaks in culture ponds. However, there is no population-based study on WSSV prevalence in PL of shrimp. The present manuscript documents the approaches and the results in the estimation of prevalence of WSSV in PL populations of Penaeus monodon at the time of stocking. A maximum of 300 PL from each of the 73 batches of PL stocked at various farms in the west coast of India during September 1999 to January 2000 were tested for the presence of WSSV by 2-step nested PCR. Thirty-six (49%) of the 73 batches tested positive for WSSV either by 1-step alone (3 batches) or after 2-step nested PCR (33 batches). Sub-samples of 5 PL each or 1 PL each tested to quantify the proportion of infected PL within batches showed that WSSV prevalence was very high in 1-step PCR-positive batches and low in 2-step PCR-positive batches. The study also showed that appropriate sampling and sample size were major factors in determining the prevalence of WSSV in PL populations, underlining the need for testing large samples of PL to reduce errors from falsely negative results.

Animals↗

Detection of hepatopancreatic parvovirus in Thai shrimp Penaeus monodon by in situ hybridization, dot blot hybridization and PCR amplification.

Hepatopancreatic parvovirus (HPV) infects the hepatopancreas in penaeid shrimp and retards their growth. The DNA sequence of HPV from Thai shrimp Penaeus monodon (HPVmon) differs from HPV of Penaeus chinensis (HPVchin) by approximately 30%. In spite of this difference, commercial PCR primers (DiagXotics) developed from HPVchin to yield a 350 bp PCR product do give a 732 bp product with HPVmon DNA template. On the other hand, the sensitivity of HPVmon detection with these primers and with hybridization probes designed for HPVchin is significantly lower than it is with HPVchin. To improve sensitivity for HPVmon detection, we used the sequence of the 732 bp HPVmon PCR amplicon described above to develop specific PCR primers (H441F and H441R) and hybridization probe. The primers could detect as little as 1 fg of purified HPVmon DNA while the 441 bp digoxygenin-labeled PCR product gave strong, specific reactions with in situ hybridization and with hybridization blots. In contrast, negative results were obtained using DNA from all other pathogens tested and from DNA of P. monodon. Supernatant solution from boiled, fresh shrimp fecal and postlarval samples homogenized in 0.025% NaOH/0.0125% SDS could be used to detect as little as 0.1 pg HPVmon DNA by the PCR reaction. By dot blot hybridization, a visible signal was obtained with purified HPVmon DNA at 0.01 pg, but detection in spiked feces and postlarval samples was only 1 and 0.1 pg, respectively.

Animals↗

White spot syndrome virus (WSSV) infects specific hemocytes of the shrimp Penaeus merguiensis.

White spot syndrome virus (WSSV) was specifically detected by PCR in Penaeus merguiensis hemocytes, hemolymph and plasma. This suggested a close association between the shrimp hemolymph and the virus. Three types of hemocyte from shrimp were isolated using flow cytometry. Dynamic changes of the hemocyte subpopulations in P. merguiensis at different times after infection were observed, indicating that the WSSV infection selectively affected specific subpopulations. Immunofluorescence assay (IFA) and a Wright-Giemsa double staining study of hemocyte types further confirmed the cellular localization of the virus in the infected hemocytes. Electron microscopy revealed virus particles in both vacuoles and the nucleus of the semigranular cells (SGC), as well as in the vacuoles of the granular cells (GC). However, no virus could be detected in the hyaline cells (HC). Our results suggest that the virus infects 2 types of shrimp hemocytes--GCs and SGCs. The SGC type contains higher virus loads and exhibits faster infection rates, and is apparently more susceptible to WSSV infection.

Animals↗

Microsporidians in penaeid shrimp along the west coast of Madagascar.

Three species of penaeid shrimp, Fenneropenaeus indicus, Penaeus monodon and P. semisulcatus, found in trawler catches off the west coast of Madagascar were infected with microsporidian parasites. The infections were evident as muscular lesions with a cottony appearance when abundant. Spore size (2.6 x 1.6 microm) and morphology (ovoid) for the parasites infecting both F. indicus and P. semisulcatus were not significantly different, suggesting that they might be the same microsporidian species. Spore size (1.4 x 1.1 microm) and morphology (sub-globose to ovoid) in P. monodon infections were significantly different from those in the other 2 shrimp species, suggesting that it was a different parasite. The presence of microsporidians in this biogeographical zone means that there is a potential risk of infections of cultured shrimp in farms situated in the vicinity. This must be assessed by increasing current knowledge of the parasites.

Animals↗

Pathology and ultrastructure of an intranuclear bacilliform virus (IBV) infecting brown shrimp Crangon crangon (Decapoda: Crangonidae).

The brown shrimp Crangon crangon supports an important fishery in Europe (over 25000 t, valued at 80 million euros in 2000). Through the course of histopathological screening of crustaceans from the Clyde estuary, western Scotland, for the biological effect of contaminants, we have discovered a highly prevalent (up to 100%) non-occluded intranuclear bacilliform virus (IBV) infection in the hepatopancreatic tubule epithelia and midgut epithelia of wild C. crangon. This is the first report of an IBV in this family. We have termed this virus Crangon crangon bacilliform virus (CcBV). Histological and ultrastructural observations suggest that this virus is similar to other IBVs previously described from crabs and penaeid shrimps. The nuclei of virus-infected epithelial cells contained an eosinophilic, hypertrophied viroplasm that marginalised the chromatin of the host nucleus. Infected cells were often separated from their neighbouring cells and their nuclei appeared apoptotic. In heavily infected shrimp, apoptotic cells were expelled into the lumen of the hepatopancreatic tubule or the midgut. Following this stage, some hepatopancreatic tubules became degenerate, with remnants of the basement membrane and myoepithelial lining remaining. Transmission electron microscopy of hypertrophic nuclei revealed the presence of rod-shaped and cylindrical, envelope-bound virions. These virions did not form arrays and were not embedded within occlusion bodies, but did appear to be partially occluded in an amorphous matrix that corresponded to a granular viroplasm. The ultrastructure, morphology and size of the nucleocapsid and the complete virion aligns the virus most closely to the IBVs previously reported from other decapod crustaceans. Due to the pathological manifestation of IBV infection in C. crangon, it appears likely that it can act as a population modulator, particularly at sites where infection prevalence is high, such as that observed in the Clyde estuary.

Animals↗

Vibrio alginolyticus infection in the white shrimp Litopenaeus vannamei confirmed by polymerase chain reaction and 16S rDNA sequencing.

A gram-negative, rod-shaped bacterium identified as Vibrio alginolyticus was isolated from diseased Litopenaeus vannamei (also called Penaeus vannamei) in Taiwanese culture ponds. The diseased shrimp displayed poor growth, anorexia, inactivity, reddish pleural borders of antennae, uropods and telson, opaque and whitish musculature, and mortality. In histological preparations, melanized hemocytic granulomas were observed in the connective tissue around hemal sinuses together with hemocytic aggregation in necrotic musculature. Six isolates of Vibrio were collected from diseased shrimp at 3 farms, and these were evaluated for characteristics including morphology, physiology, biochemistry and sensitivity to antibiotics. The results indicated that the isolates belonged to a single species that grew in 1 to 8% NaCl, at 10 to 40 degrees C and on TCBS (thiosulfatecitrate-bile sucrose) agar, and that gave positive catalase, O/F (Oxidation/Fermentation), lysine decarboxylase, gelatinase and cytochrome-oxidase tests. Identification of CH003 (1 of 6 isolates) was confirmed by PCR assay for V. alginolyticus (expected amplicon 1486 bp). The 16S rDNA sequence (GenBank accession number AY373027) gave 99.9% sequence identity to V. alginolyticus (GenBank accession number X74690). The calculated 96 h LD50 dose of the isolated strain was 3.0 x 10(5) colony forming units (CFU) shrimp(-1) (6.6 x 10(4) CFU g(-1)).

Animals↗