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Sirawut Klinbunga - One of the best experts on this subject based on the ideXlab platform.
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characterization and expression analysis of cyclin dependent kinase 7 gene and protein in ovaries of the giant tiger shrimp penaeus Monodon
Aquaculture, 2014Co-Authors: Mahattanee Phinyo, Sirawut Klinbunga, Padermsak Jarayabhand, Pachumporn Nounurai, Rachanimuk HiransuchalertAbstract:Abstract The characterization of genes differentially expressed in ovaries is necessary for understanding the mechanisms involving ovarian developmental processes of the giant tiger shrimp ( Penaeus Monodon ). Here, the full-length cDNA of P. Monodon Cyclin-dependent kinase 7 ( PmCdk7 ) was characterized. It was 1407 bp in length (ORF of 1062 bp corresponding to 353 amino acids). The expression of PmCdk7 in the ovaries was greater than that in the testes ( P PmCdk7 was significantly up-regulated in stage IV (mature) ovaries in wild intact broodstock ( P P PmCdk7 during ovarian development (stages I–IV ovaries) in eyestalk-ablated broodstock was greater than that of the same ovarian stages in intact broodstock ( P P. Monodon.
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identification characterization and expression of sex related genes in testes of the giant tiger shrimp penaeus Monodon
Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2009Co-Authors: Rungnapa Leelatanawit, Sirawut Klinbunga, Takashi Aoki, Ikuo Hirono, Piamsak Menasveta, Kanchana Sittikankeaw, Patchari Yocawibun, Sittiruk RoytrakulAbstract:Isolation and characterization of genes involving gonadal development are an initial step towards understanding reproductive maturation and sex determination of the giant tiger shrimp (Penaeus Monodon). In the present study, 896 clones from the testis cDNA library were sequenced. A total of 606 ESTs (67.6%) significantly matched sequences in the GenBank (E-value <1e-04) whereas 290 ESTs (32.4%) were newly unidentified transcripts. The full length cDNA of genes functionally involved in testicular development including cyclophilin A (PMCYA), small ubiquitin-like modifier 1 (PMSUMO-1), ubiquitin conjugating enzyme E2, dynactin subunit 5, cell division cycle 2 (cdc2) and mitotic checkpoint BUB3 were discovered. In addition, Tra-2, a gene involving sex determination cascades, was successfully characterized by RACE-PCR and first reported in crustaceans. Expression analysis indicated that a homologue of low molecular weight neurofilament protein XNF-L (termed P. Monodon testis-specific transcript 1, PMTST1; N=8 for each sex) was only expressed in testes but not ovaries. PMCYA, thyroid hormone receptor-associated protein complex 240 kDa component (Trap240), multiple inositol polyphosphate phosphatase 2 (MIPP2) and heat shock-related 70 kDa protein 2 (HSP70-2), but not PMSUMO-1, PMTra-2 and prohibitin2 were differentially expressed between ovaries and testes of P. Monodon. Expression of PMTST1 was up-regulated but that of the remaining genes in testes of P. Monodon broodstock was down-regulated after shrimp were molted (P<0.05). Significant reduction of PMSUMO-1 and increment of prohibitin2 transcripts in domesticated broodstock (P<0.05) suggested that these reproductively related genes may be used as biomarkers to evaluate reduced degrees of the reproductive maturation in domesticated P. Monodon.
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expressed sequence tag analysis for identification and characterization of sex related genes in the giant tiger shrimp penaeus Monodon
Journal of Biochemistry and Molecular Biology, 2007Co-Authors: Rachanimuk Preechaphol, Sirawut Klinbunga, Bavornlak Khamnamtong, Rungnapa Leelatanawit, Kanchana Sittikankeaw, Narongsak Puanglarp, Piamsak MenasvetaAbstract:Sex-related genes expressed in vitellogenic ovaries of the giant tiger shrimp, Penaeus Monodon, were identified by an EST approach. A total of 1051 clones were unidirectionally sequenced from the 5 terminus. Nucleotide sequences of 743 EST (70.7%) significantly matched known genes previously deposited in the GenBank (E-value 10(-4)). A total of 559 transcripts (87 contigs and 472 singletons) were obtained. Thrombospondin (TSP) and peritrophin (79 and 87 clones accounting for 7.5 and 8.3% of clones sequenced, respectively) predominated among characterized transcripts. Several full length transcripts (e.g. cyclophilin, profillin and thioredoxin peroxidase) were also isolated. A gene homologue encoding chromobox protein (PMCBX, ORF of 567 nucleotides encoding a protein of 188 amino acids) which is recognized as a new member of the HP1 family was identified. Expression patterns of 14 of 25 sex-related gene homologues in ovaries and testes of P. Monodon broodstock were examined by RT-PCR. Female sterile and ovarian lipoprotein receptor homologues were only expressed in ovaries whereas the remaining transcripts except disulfide isomerase related P5 precursor and adenine nucleotide translocator 2 were higher expressed in ovaries than testes of P. Monodon broodstock. A homologue of ubiquitin specific proteinase 9, X chromosome (Usp9X) revealed a preferential expression level in ovaries than testes of broodstock-sized P. Monodon (N = 13 and 11, P <0.05) but was only expressed in ovaries of 4-month-old shrimp (N = 5 for each sex).
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development of polymorphic expressed sequence tag derived microsatellites for the extension of the genetic linkage map of the black tiger shrimp penaeus Monodon
Animal Genetics, 2006Co-Authors: C Maneeruttanarungroj, Sirawut Klinbunga, Siriporn Pongsomboon, S Wuthisuthimethavee, Kate J Wilson, Jennie Swan, Vicki WhanAbstract:In this study, microsatellite markers were developed for the genetic linkage mapping and breeding program of the black tiger shrimp Penaeus Monodon. A total of 997 unique microsatellite-containing expressed sequence tags (ESTs) were identified from 10 100 EST sequences in the P. Monodon EST database. AT-rich microsatellite types were predominant in the EST sequences. Homology searching by theblastnandblastxprograms revealed that these 997 ESTs represented 8.6% known gene products, 27.8% hypothetical proteins and 63.6% unknown gene products. Characterization of 50 markers on a panel of 35-48 unrelated shrimp indicated an average number of alleles of 12.6 and an average polymorphic information content of 0.723. These EST microsatellite markers along with 208 other markers (185 amplified fragment length polymorphisms, one exon-primed intron-crossing, six single strand conformation polymorphisms, one single nucleotide polymorphism, 13 non-EST-associated microsatellites and two EST-associated microsatellites) were analysed across the international P. Monodon mapping family. A total of 144 new markers were added to the P. Monodon maps, including 36 of the microsatellite-containing ESTs. The current P. Monodon male and female linkage maps have 47 and 36 linkage groups respectively with coverage across half the P. Monodon genome.
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Identification of sex-specific expression markers in the giant tiger shrimp (Penaeus Monodon).
Journal of biochemistry and molecular biology, 2006Co-Authors: Bavornlak Khamnamtong, Sirawut Klinbunga, Supaporn Thumrungtanakit, Takashi Aoki, Ikuo Hirono, Piamsak MenasvetaAbstract:Bulked segregant analysis (BSA) and AFLP were used for isolation of genomic sex determination markers in Penaeus Monodon. A total of 256 primer combinations were tested against 6-10 bulked genomic DNA of P. Monodon. Five and one candidate female- and male-specific AFLP fragments were identified. Female-specific fragments were cloned and further characterized. SCAR markers derived from FE10M9520, FE10M10725.1, FE10M10725.2 and FE14M16340 provided the positive amplification product in both male and female P. Monodon. Further analysis of these markers using SSCP and genome walk analysis indicated that they were not sex-linked. In addition, sex-specific (or differential) expression markers in ovaries and testes of P. Monodon were analyzed by RAP-PCR (150 primer combinations). Twenty-one and fourteen RAP-PCR fragments specifically/differentially expressed in ovaries and testes of P. Monodon were successfully cloned and sequenced. Expression patterns of 25 transcripts were tested against the first stranded cDNA of ovaries and testes of 3-month-old and broodstock-sized P. Monodon (N=5 and N=7-10 for females and N=4 and N=5-7 for males, respectively). Five (FI-4, FI-44, FIII-4, FIII-39 and FIII-58) and two (M457-A01 and MII-51) derived RAP-PCR markers revealed female- and male-specific expression patterns in P. Monodon. Surprisingly, MII-5 originally found in testes showed a higher expression level in ovaries than did testes of juvenile shrimps but a temporal female-specific pattern in P. Monodon adults.
Donald V. Lightner - One of the best experts on this subject based on the ideXlab platform.
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infectious hypodermal and hematopoietic necrosis virus ihhnv related sequences in the genome of the black tiger prawn penaeus Monodon from africa and australia
Virus Research, 2006Co-Authors: Kathy F.j. Tang, Donald V. LightnerAbstract:We found an infectious hypodermal and hematopoietic necrosis virus (IHHNV)-related sequence within the shrimp genome in populations of Penaeus Monodon from Africa and Australia. IHHNV is a single-stranded DNA virus that has caused severe mortality and stunted growth in penaeid shrimp. Recently, IHHNV-related sequences were found in samples of P. Monodon from Madagascar and Tanzania. These sequences vary considerably (14 and 8%, respectively) from that of IHHNV found in association with viral epidemics. Laboratory bioassays were carried out with P. Monodon and Litopenaeus vannamei to determine if either of these IHHNV-related sequences is infectious. We used juvenile and adult P. Monodon containing the virus-related sequences from four geographic regions to generate inocula and tissues for feeding. Specific pathogen free P. Monodon and L. vannamei were used as indicator shrimp. During the 2-4 week bioassays, none of the indicator shrimp showed signs of infection or disease. Results of both PCR assays and histological examination of the indicator shrimp were negative for IHHNV infection, indicating that the Africa type IHHNV-related sequences are not infectious. With the shrimp containing the Madagascar type IHHNV-related sequence (designated as type A), we performed genome walking at the 3' end of the virus-related sequence and found that this virus-related sequence is part of the P. Monodon genome. A fragment of 1.9 kb flanking sequence was cloned and sequenced. Sequence analysis showed that this flanking sequence contains shrimp microsatellite DNA. Also, its translated amino acid sequence was highly similar to a retrotransposon. This result provides molecular evidence that the type A IHHNV-related sequence is shrimp DNA. This sequence was found in the P. Monodon collected from Africa and Australia.
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Different responses to infectious hypodermal and hematopoietic necrosis virus (IHHNV) in Penaeus Monodon and P. vannamei.
Diseases of aquatic organisms, 2005Co-Authors: Kanokporn Chayaburakul, Donald V. Lightner, Siriporn Sriurairattana, Kathy Tang Nelson, Boonsirm WithyachumnarnkulAbstract:Infectious hypodermal and hematopoietic necrosis virus (IHHNV) is widespread in cultured Penaeus Monodon and P. vannamei in Thailand. It causes runt-deformity syndrome that is characterized by physical abnormalities and stunted growth in P. vannamei, but causes no apparent disease in P. Monodon. In both species, the virus may produce Cowdry Type A inclusions in tissues of ectodermal and mesodermal origin, but these are common in P. vannamei and rare in P. Monodon. The virus can be more easily detected in both species by IHHNV-specific PCR primers. By in situ hybridization (ISH) using specific IHHNV probes, fixed phagocytes associated with myocardial cells tended to show strong positive reactions in both shrimp species. Ovarian and neural tissue (neurons in the nerve ganglia and glial cells in the nerve cord) were ISH positive for IHHNV only in P. vannamei. By transmission electron microscopy, necrotic cells were found in the gills of IHHNV-infected P. vannamei, while paracrystalline arrays of virions and apoptotic cells rather than necrotic cells were found in the lymphoid organ of IHHNV-infected P. Monodon. Thus, it is possible that apoptosis in P. Monodon contributes to the absence of clinical disease from IHHNV. These findings reveal different responses to IHHNV infection by the 2 shrimp species. A curious feature of IHHNV infection in P. Monodon was inconsistency in the comparative viral load amongst tissues of different specimens, as detected by both ISH and real-time PCR. This inconsistency in apparent tissue preference and the reasons for different cellular responses between the 2 shrimp species remain unexplained.
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Experimental infection of Penaeus Monodon with Taura syndrome virus (TSV).
Diseases of Aquatic Organisms, 2005Co-Authors: Thinnarat Srisuvan, Kathy F.j. Tang, Donald V. LightnerAbstract:Clinical signs and lesions of Taura syndrome virus (TSV) infection in Penaeus Monodon have not been documented although the virus has been detected in this shrimp species by reverse transcription polymerase chain reaction (RT-PCR). This study provides the first evidence of TSV infection in P. Monodon by histological and in situ hybridization (ISH) analyses. We performed experimental bioassays with groups of P. Monodon using inocula of P. Monodon and Litopenaeus vannamei (Th04PmTSV and Th04LvTSV, respectively), which were collected from Thailand in 2004 and found to be positive for TSV by RT-PCR. Samples of shrimp for histological and ISH analyses were collected on Days 2, 14, and 28 post-inoculation. Mortality among TSV-inoculated P. Monodon appeared on Day 3, with 2 out of 10 shrimp dying. Severe necrosis of cuticular epithelial cells and lymphoid organ spheroids, indicative of acute and chronic phase lesions of TSV infection, respectively, were detected in the samples. Sequence analyses of the capsid protein 2 (CP2) gene showed that Th04PmTSV and Th04LvTSV isolates were different; however, both belonged to a phylogenetic family of Asian TSV isolates. The results of this study demonstrated that both mortality and histological lesions are associated with TSV infection in P. Monodon.
Jiann-chu Chen - One of the best experts on this subject based on the ideXlab platform.
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Photobacterium damselae ssp. damselae associated with diseased black tiger shrimp Penaeus Monodon Fabricius in India
Letters in applied microbiology, 2007Co-Authors: Baskaralingam Vaseeharan, S. Sundararaj, T. Murugan, Jiann-chu ChenAbstract:Aim: To characterize and identify Photobacterium damselae ssp. damselae present in black gill diseased Penaeus Monodon collected from east coast of India. Methods and Results: Photobacterium damselae ssp. damselae was isolated from hepatopancreas, muscles and gills by using the thiosulfate citrate bile salts sucrose agar supplemented with 1·5% NaCl (TCBS-1) medium. A total of 32 Ph. damselae ssp. damselae isolates were studied together with two reference strains. The biochemical tests and analysis of ureC and 16S rRNA genes confirmed the phenotypic characterization of the isolates as Ph damselae ssp. damselae. Experimental infection studies revealed that the LD50 values of P. Monodon and P. indicus ranged from 2 × 103 to 5 × 105 CFU per shrimp and from 4 × 102 to 2 × 104 CFU per shrimp, respectively. Conclusions: Photobacterium damselae ssp. damselae was found in the internal organs of P. Monodon and it showed pathogenic to shrimp. Significance and Impact of the Study: This is the first study on the Ph. damselae ssp. damselae present in the black gill diseased P. Monodon in India and therefore might serve as a basis for future studies and diagnosis purpose to shrimp culturists.
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Acute toxicity of nitrate on Penaeus Monodon juveniles at different salinity levels
Aquaculture, 2002Co-Authors: Su-jun Tsai, Jiann-chu ChenAbstract:Abstract Penaeus Monodon juveniles (total length 28.4±6.2 mm) were exposed to different concentrations of nitrate–N (nitrate as nitrogen) using the static renewal method at different salinity levels. The 48-, 72-, 96-h LC50s (median lethal concentrations) of nitrate–N for P. Monodon juveniles were 2876, 1723, 1449 mg/l in seawater of 15‰ (g/kg); 3894, 2506, 1575 mg/l in 25‰; 4970, 3525, 2316 mg/l in 35‰, respectively. The “safe level” for rearing juvenile P. Monodon was estimated to be 145, 158 and 232 mg/l nitrate–N in 15‰, 25‰ and 35‰, respectively. The relationship between LC50 of nitrate–N (mg/l), salinity (S), exposure time (t) and the interaction between salinity and exposure time (St) is as follows: LC 50=3917.467+102.456S−42.634t−0.342 St (R 2 =0.775)
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Toxicity of copper sulfate for survival, growth, molting and feeding of juveniles of the tiger shrimp, Penaeus Monodon
Aquaculture, 2001Co-Authors: Jiann-chu Chen, Chia-hsin LinAbstract:Abstract The aim of this study was to determine the acute and chronic toxicity of copper sulfate for juveniles of Penaeus Monodon . The 96-h LC50s (median lethal concentrations) of copper on juvenile P. Monodon (0.63±0.13 g) were 3.13 and 7.73 mg/l in seawater of 15‰ and 25‰, respectively. The mortality rates of P. Monodon juveniles (0.19±0.02 g) following exposure to 0 (control), 0.45, 0.90, 1.80 and 4.50 mg/l copper after 30 days was 0%, 0%, 5.6%, 22.2% and 55.6%, respectively. After 30 days of exposure, the body weight and total length of shrimps exposed to copper at 0.90 mg/l and higher was significantly lower ( P P P. Monodon shortened the time to the first molt, and decreased its growth and molting frequency. Following exposure to copper as low as 5.0 mg/l, P. Monodon juveniles (6.25±0.09 g) decreased their feeding. The MATC (maximum acceptable toxicant concentration) was 0.45 mg/l copper based on the growth and molting of shrimps weighing 0.18–1.03 g, and was 1.0 mg/l copper based on the feeding of shrimps weighing 6.25 g.
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Cholesterol requirement of juvenile tiger shrimp (Penaeus Monodon)
Aquaculture, 1994Co-Authors: Shyn-shin Sheen, Shiu-nan Chen, Ping-chung Liu, Jiann-chu ChenAbstract:Abstract The effect of dietary cholesterol on the growth and survival of juvenile tiger shrimp ( Penaeus Monodon ) was tested using semi-purified diets. Twenty-four shrimp per treatment, with an initial mean weight of 268.2 mg, were individually housed in black nylon mesh pots in 40-liter aquaria containing 30 ppt seawater. Diets containing 0, 0.2, 0.4, 0.5, 0.8, and 1.0% supplemental cholesterol were evaluated. The duration of the experiment was 63 days. Shrimp fed diets containing 0% and 1% cholesterol had significantly lower weight gain and poorer survival than those fed the other diets. There was no significant difference in weight gain of P. Monodon fed diets containing 0.2–0.8% cholesterol. A diet containing 1% cholesterol had an adverse or toxic effect on P. Monodon growth.
Iddya Karunasagar - One of the best experts on this subject based on the ideXlab platform.
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Detection of viruses in Penaeus Monodon from India showing signs of slow growth syndrome
Aquaculture, 2009Co-Authors: Praveen Rai, Balakrishnan Pradeep, Iddya KarunasagarAbstract:Abstract The presence of viruses implicated in slow growth of Penaeus Monodon , hepatopancreatic parvovirus (HPV), Monodon baculovirus (MBV), infectious hypodermal and hematopoietic necrosis virus (IHHNV) and Laem–Singh virus (LSNV) was studied by polymerase chain reaction (PCR) in 72 P. Monodon samples, which showed slow growth rate. The prevalence of IHHNV was highest 18/72 (25%) followed by HPV 5/72 (6.9%), LSNV 3/72 (4.2%) and MBV 3/72 (4.2%). Further, 20/72 (27.7%) samples were positive for WSSV and 18/72 (25%) had clinical conditions typical of Monodon slow growth syndrome (MSGS) of which eight samples had IHHNV, two had LSNV and remaining eight were free from all known slow growth viruses. In a hatchery based study, 71 post larval samples were analysed and the incidence of IHHNV was highest 44/71 (61.9%) followed by MBV 7/71 (9.8%), HPV 6/71 (8.4%) and WSSV 2/71 (2.8%). Hatchery rearing of IHHNV infected P. Monodon nauplii up to 50 days confirmed the virus to be responsible for slow growth. The study suggests the presence of IHHNV in India and indicates that this virus could be one of the causes of slow growth in cultured P. Monodon .
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Detection by PCR of hepatopancreatic parvovirus (HPV) and other viruses in hatchery-reared Penaeus Monodon postlarvae
Diseases of aquatic organisms, 2003Co-Authors: Rudrappa K. Umesha, Iddya Karunasagar, S.k. Otta, Arumugam Uma, Iddya KarunasagarAbstract:The prevalence of hepatopancreatic parvovirus (HPV), Monodon baculovirus (MBV) and white spot syndrome virus (WSSV) in samples of Penaeus Monodon postlarvae (PL10 to PL20, 10 to 20 d old postlarvae) in India was studied by PCR. Samples collected from different hatcheries, and also samples submitted by farmers from different coastal states, were analyzed. HPV was detected in 34% of the hatchery samples and 31% of the samples submitted by farmers, using a primer set designed for detection of HPV from P. Monodon in Thailand. However, none of these samples were positive using primers designed for detection of HPV from P. chinensis in Korea. This indicated that HPV from India was more closely related to HPV from P. Monodon in Thailand. MBV was detected in 64% of the samples submitted by the farmers and 71% of the hatchery samples. A total of 84% of the samples submitted by farmers, and 91% of the hatchery samples, were found positive for WSSV. Prevalence of concurrent infections by HPV, MBV and WSSV was 27% in hatchery samples and 29% in samples submitted by farmers. Only 8% of the hatchery samples and 16% of the samples submit- ted by farmers were negative for all 3 viruses. This is the first report on the prevalence of HPV in P. Monodon postlarvae from India.
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Multiple viral infection in Penaeus Monodon shrimp postlarvae in an Indian hatchery.
Diseases of aquatic organisms, 2002Co-Authors: Subramaniyan Manivannan, Iddya Karunasagar, S.k. Otta, Iddya KarunasagarAbstract:Moribund Penaeus Monodon postlarvae (PL8-PL10) in a hatchery in India were found to be simultaneously infected by 3 different viruses. They were highly infected with Monodon baculovirus (MBV) and hepatopancreatic parvovirus (HPV) by histology and with white spot syndrome virus (WSSV) by non-nested polymerase chain reaction (PCR). Apparently healthy postlarvae tested from the same hatchery were positive for MBV and WSSV by nested PCR only. Tissue sections of such postlarvae did not show any histopathological changes. The simultaneous occurrence of these 3 viruses in hatchery-reared postlarval P. Monodon is being reported for the first time.
Boonsirm Withyachumnarnkul - One of the best experts on this subject based on the ideXlab platform.
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molecular characterization of gonad inhibiting hormone of penaeus Monodon and elucidation of its inhibitory role in vitellogenin expression by rna interference
FEBS Journal, 2008Co-Authors: Supattra Treerattrakool, Boonsirm Withyachumnarnkul, Sakol Panyim, Siuming Chan, Apinunt UdomkitAbstract:One of the important peptide hormones that control reproduction in crustaceans is gonad-inhibiting hormone (GIH). GIH is known to modulate gonad maturation by inhibiting synthesis of vitellogenin (Vg), the precursor of yolk proteins. In this study, a cDNA encoding a GIH (Pem-GIH) from the eyestalk of Penaeus Monodon was cloned using RT-PCR and RACE techniques. Pem-GIH cDNA is 861 bp in size with a single ORF of 288 bp. The deduced Pem-GIH consists of a 17-residue signal peptide and a mature peptide region of 79 amino acids with features typical of type II peptide hormones from the CHH family. Pem-GIH transcript was detected in eyestalk, brain, thoracic and abdominal nerve cords of adult P. Monodon. The gonad-inhibiting activity of Pem-GIH was investigated using the RNA interference technique. Double-stranded RNA, corresponding to the mature Pem-GIH sequence, can trigger a decrease in Pem-GIH transcript levels both in eyestalk ganglia and abdominal nerve cord explant culture and in female P. Monodon broodstock. The conspicuous increase in Vg transcript level in the ovary of GIH-knockdown shrimp suggests a negative influence for Pem-GIH on Vg gene expression, and thus implies its role as a gonad-inhibiting hormone. This is the first report to demonstrate the use of double-stranded RNA to elucidate the function of GIH in P. Monodon.
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Serotonin stimulates ovarian maturation and spawning in the black tiger shrimp Penaeus Monodon
Aquaculture, 2006Co-Authors: Kanokpan Wongprasert, Somluk Asuvapongpatana, Pisit Poltana, Montip Tiensuwan, Boonsirm WithyachumnarnkulAbstract:Abstract Serotonin (5-hydroxytryptamine, 5HT) has been reported to induce ovarian maturation and spawning in the crayfish Procambarus clarkii and white Pacific shrimp Litopenaeus vannamei . The aim of this study was to explore the role of exogenous 5HT on the reproductive performance of the black tiger shrimp Penaeus Monodon . 5HT solution was injected into domesticated P. Monodon broodstock at 50 μg/g body weight and ovarian maturation and spawning were recorded. The presence of 5HT in the ovary and oviduct of P. Monodon was also studied by immunohistochemistry and its levels in the ovary by enzyme link immunoabsorbance assay (ELISA). The 5HT-injected P. Monodon developed ovarian maturation and spawning rate at the level comparable to that of unilateral eyestalk-ablated shrimp. Hatching rate and the amount of nauplii produced per spawner were also significantly higher in the 5HT-injected shrimp, compared to the eyestalk-ablated shrimp. 5HT-positive reactions were found in the follicular cells of pre-vitellogenic oocytes, in the cytoplasm of early vitellogenic oocytes and on the cell membrane and cytoplasm of late vitellogenic oocytes. 5HT in the ovary was present at 3.53 ± 0.26 ng/mg protein level in previtellogenic stage and increased to 17.03 ± 0.57 ng/mg protein level in the mature stage of the ovary. The results suggest a significant role of 5HT, possibly directly on the ovary and oviduct, on the reproductive function of female P. Monodon .
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Different responses to infectious hypodermal and hematopoietic necrosis virus (IHHNV) in Penaeus Monodon and P. vannamei.
Diseases of aquatic organisms, 2005Co-Authors: Kanokporn Chayaburakul, Donald V. Lightner, Siriporn Sriurairattana, Kathy Tang Nelson, Boonsirm WithyachumnarnkulAbstract:Infectious hypodermal and hematopoietic necrosis virus (IHHNV) is widespread in cultured Penaeus Monodon and P. vannamei in Thailand. It causes runt-deformity syndrome that is characterized by physical abnormalities and stunted growth in P. vannamei, but causes no apparent disease in P. Monodon. In both species, the virus may produce Cowdry Type A inclusions in tissues of ectodermal and mesodermal origin, but these are common in P. vannamei and rare in P. Monodon. The virus can be more easily detected in both species by IHHNV-specific PCR primers. By in situ hybridization (ISH) using specific IHHNV probes, fixed phagocytes associated with myocardial cells tended to show strong positive reactions in both shrimp species. Ovarian and neural tissue (neurons in the nerve ganglia and glial cells in the nerve cord) were ISH positive for IHHNV only in P. vannamei. By transmission electron microscopy, necrotic cells were found in the gills of IHHNV-infected P. vannamei, while paracrystalline arrays of virions and apoptotic cells rather than necrotic cells were found in the lymphoid organ of IHHNV-infected P. Monodon. Thus, it is possible that apoptosis in P. Monodon contributes to the absence of clinical disease from IHHNV. These findings reveal different responses to IHHNV infection by the 2 shrimp species. A curious feature of IHHNV infection in P. Monodon was inconsistency in the comparative viral load amongst tissues of different specimens, as detected by both ISH and real-time PCR. This inconsistency in apparent tissue preference and the reasons for different cellular responses between the 2 shrimp species remain unexplained.
