scholarly journals Determination of the Infectious Agent of Translucent Post-Larva Disease (TPD) in Penaeus vannamei

Pathogens ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 741 ◽  
Author(s):  
Ying Zou ◽  
Guosi Xie ◽  
Tianchang Jia ◽  
Tingting Xu ◽  
Chong Wang ◽  
...  

A new emerging disease called “translucent post-larvae disease” (TPD) or “glass post-larvae disease” (GPD) of Penaeus vannamei, characterized by pale or colorless hepatopancreas and digestive tract, has become an urgent threat to the shrimp farming industry. Following this clue that treatment of an antibacterial agent could alleviate the disease, systematic investigation of the potential infectious agent of TPD was conducted using bacterial identification and artificial challenge tests to fulfill Koch’s postulates. A dominant bacterial isolate, Vp-JS20200428004-2, from the moribund individuals was isolated and identified as Vibrio parahaemolyticus based on multi-locus sequence analysis. However, Vp-JS20200428004-2 differed from the V. parahaemolyticus that caused typical acute hepatopancreatic necrosis disease. Immersion challenge tests revealed that Vp-JS20200428004-2 could cause 100% mortality within 40 h at a dose of 1.83 × 106 CFU/mL, and experimental infected shrimp showed similar clinical signs of TPD. The Vp-JS20200428004-2 could be re-isolated and identified from the experimental infected individuals. Moreover, histopathological analysis of diseased samples indicated that Vp-JS20200428004-2 caused severe necrosis and sloughing of epithelial cells of the hepatopancreas and midgut in shrimp individuals both naturally and experimentally infected. Our present results indicated that Vp-JS20200428004-2 is a highly virulent infectious agent associated with the TPD and deserves further attention.

2017 ◽  
Vol 47 (10) ◽  
Author(s):  
Gabriela Fredo ◽  
Ronaldo Viana Leite-Filho ◽  
Camila De Ávila Pietzsch ◽  
Caroline Pinto de Andrade ◽  
Naila Cristina Blatt Duda ◽  
...  

ABSTRACT: In the period from January 2004 to December 2015, 56 dogs were diagnosed with rangeliosis in the Setor de Patologia Veterinária at Universidade Federal do Rio Grande do Sul (SPV-UFRGS). The main hematological abnormalities were thrombocytopenia and anemia. The affected dogs showed signs of apathy, anorexia, fetid and bloody diarrhea, vomiting, and dehydration. At necropsy, the main changes were jaundice, splenomegaly, hepatomegaly, and lymphadenomegaly. Histological analyses revealed parasitophorous vacuoles of Rangelia vitalii in cytoplasmic endothelial cells, mainly in the heart, kidneys, lymph nodes, intestines, and pancreas. Inflammation characterized by mononuclear cells was predominant in the analysis, and most was due to the presence of plasma cells. Other lesion types observed were lymphoid hyperplasia, extramedullary hematopoiesis, erythrophagocytosis, and erythroid lineage hyperplasia in bone marrow. Of the total number of animals, 49 were diagnosed using necropsy and histological analysis, and seven were diagnosed using a molecular analysis (i.e., PCR and genetic sequencing of blood samples). This paper presented a different method of diagnosing rangeliosis in canines. This approach involved histological methods including the quantification and determination of the intensity and distribution of the infectious agent in different organs.


In any aquaculture business, sustainability of a system improved profits. At present although biosecurity and BAqP are in place, more needed to be done. With emerging disease challenges innovated designs and operation systems are developing for sustainable production. One of the most important factors the investors, shrimp farmers and technicians need to be aware of is that whatever waste discharged into environment will come back to you in a form of disease sooner or later. Before mid1990s major threats to shrimp farming was mainly bacterial diseases. In Asia from late 1994 appearance of viral diseases such as white spot syndrome virus (WSSV) and a few others like yellow head virus (YHV), infectious myonecrosis virus (IMNV). In 2001 with availability of Specific Pathogen Free (SPF) Penaeus vannamei broodstock from Hawaii, the shrimp farming industry took off much faster.


Author(s):  
T. Anand ◽  
A. Srinivasan ◽  
P. Padmavathy ◽  
P. Jawahar ◽  
J. Stephen Sampathkumar

Background: Nursery rearing of Penaeus vannamei became inevitable in the Indian shrimp farming industry, since intensification of culture practices in grow-out systems caused nitrogenous wastes accumulation, diseases, mortality and premature harvests resulted in high food conversion ratio, lower production and profits. The nursery rearing in traditional water exchange systems often getting failure because of nitrogenous waste accumulation. Hence, the present experiment was planned to rear P. vannamei in bioflocs systems (BFS) with different salinities and carbon sources. Methods: The experiment was conducted in 0.22 m3 tanks with three different salinity groups viz., 35 ppt, 20 ppt and 5 ppt and in each salinity sugar, molasses used as carbon sources to maintain an estimated C/N ratio of 15:1 and controls without carbon sources. Experimental tanks were stocked @6 post larvae/l, with pre-salinity acclimatized P.vannamei seeds having 0.0029±0.0003g size and nursed for a period of 5 weeks. Result: The nitrogenous waste accumulation was reduced significantly (p less than 0.05), also average body weight and survival rate of the seeds showed significant difference (p less than 0.001) between treatments and controls and within treatments (p less than 0.05). Salinity, carbon sources and their interaction influenced the growth characteristics significantly (p less than 0.01). The present experiment manifested promising results of bioflocs nurseries in rearing of P. vannamei seeds at different salinities.


Author(s):  
Adriana Vallejo Isaza ◽  
Federico Newmark U.

An epizootiological study of the mayor deseases affecting the penaeid shrimp Penaeus vannamei was performed from june 1994 throuh august, 1995 in tree farms located on the colombian Carebbean coast. The presence and prevalence of infectious agents such as bacteria, protozoa, viral inclusions bodies and changes histopatologicals was determinated by means of gross examination and histological analysis.. The relationship between these infection agents and specific disease was also studies. The presence of some viruses such a Baculovirus penaei, IHHNV, TSV and LOVV, were determinated by demostration of the cytopathical effects characteristic of these agent. Additionaly, a logistic regression analysis was used to determine the relationship between some clinical signs and the presence of the infectious agent; the risk factor of having the disease, was also determinated; thus, shrimp with tumors and deformities presented a risk almost two times higher having IHHNV disease, as determined by the presence of inclusion bodies Cowdry A (CAI’s) than those whitout deformities; in an analogous way, the risk factor of presenting alterations in the lymphoid organ (L.O) was higher in organisms that have exposed to the TSV desease, than in those were not. Bacterial infections an infestations by protozoa were also analyzed. Some differences concerning the presence and prevalence of some of the diseases according to the geographical location of the farms and the different climatic conditions in such the cultivation started, wer observed. Some physical-chemical variables such as salinity, where related to the presence and prevalence of some clinical signs.


2009 ◽  
Vol 4 (2) ◽  
pp. 109
Author(s):  
Coco Kokarkin Soetrisno

White spot syndrome virus is recognized as the most prominent pathogen of penaeid shrimp and has been affecting this shrimp farming industry around the world. The virus may reduce the shrimp’s immune response and alter enzymatic and biochemical composition of tissues. Similar to other environmental stressed or other pathogeninfected shrimp, in late stages of WSSV infection, shrimp will fail to clot the haemolymph, so any minor injury will lead to increased haemolyph loss. A series of experiments to determine the effect of non-clotting haemolymph on WSSV infection were carried out in controlled facilities in Indonesia. The preliminary test showed that normal clotting time was 13.3 seconds while WSSV-injected shrimp mostly failed to clot their haemolymph 16 hours post infection (hpi). Some other clinical signs such as abnormal swimming, red discoloration, white spots and mortality were consistent with those observed by previous studies. Three shrimp species: banana shrimp (P. merguiensis) 9 g , white leg shrimp (P. vannamei) 7 g and the tiger shrimp (P. monodon) 16.5 g were water-borne-challenged with non-clotting, WSSV-infected haemolymph (NCH) from tiger shrimp donor in duplicate tanks each with 12 shrimp. The control were tiger shrimps fed with WSSV-infected tissue at the rate of 40% of bodyweight (BW) and other tiger shrimps were used as negative controls fed with commercial feed only.The study revealed that NCH dosages of 1.46%; 2.03%; and 2.06% (v/v) for eachspecies were sufficient to infect and kill all shrimps in less than two days comparedto eight days for the shrimps fed on infected tissue. The WSSV in non-clottedhaemolymph eventuallyattaches into the living tissues of healthy shrimp. This modeof infection is likely more difficult to control by the ordinary fine mesh screeningmethod.


2021 ◽  
Vol 10 (4) ◽  
pp. 811
Author(s):  
Taketoshi Ide ◽  
Takamichi Ito ◽  
Maiko Wada-Ohno ◽  
Masutaka Furue

The efficacy of preoperative imaging for acral melanoma (AM) has not been fully evaluated. We examined the accuracy of imaging modalities in the detection of nodal and distant metastases in patients with AM. A retrospective review of 109 patients with AM was performed. All patients had no clinical signs suggestive of distant metastases, and underwent preoperative screening computed tomography (CT) and positron emission tomography (PET)/CT scans. Of 100 patients without lymphadenopathy, 17 patients were suspected of having nodal metastasis in CT and PET/CT, but only two of them were confirmed on histopathological analysis. On the other hand, 12 out of 83 negatively imaged patients showed histopathological signs of nodal metastasis; thus, the sensitivity and specificity of nodal detection were 14.3% and 82.6%, respectively. Regard to the detection of distant metastases, four patients were suspected of having metastasis, but this was later ruled out. The remaining 96 negatively imaged patients were confirmed to have no metastasis at the time of CT and PET/CT by the follow-up. In contrast, distant metastases were found by CT and PET/CT in four of nine patients (44.4%) with lymphadenopathy. Routine preoperative CT and PET/CT for AM patients without lymphadenopathy may not be warranted because of low sensitivity and specificity, but it can be considered for those with lymphadenopathy.


Biology ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 280
Author(s):  
Linh Nguyen Thi Truc ◽  
Tuu Nguyen Thanh ◽  
To Tran Thi Hong ◽  
Day Pham Van ◽  
Minh Vo Thi Tuyet ◽  
...  

This study aimed to evaluate the growth, survival rate, and resistance to acute hepatopancreatic necrosis disease (AHPND) of white leg shrimp (Penaeus vannamei) by using Lactobacillus plantarum, Lactobacillus fermentum, and Pediococcus pentosaceus mixed with feed, and at the same time supplying CNP in a ratio of 15:1:0.1 to the water. As a result, the treatments that shrimp were fed with feed containing lactic acid bacteria (LAB), especially L. plantarum, have increased shrimp growth, total hemocyte cells, granulocyte cells, and hyaline cells significantly (p < 0.05) in comparison to the control group. The supply of CNP to the water has promoted the intensity of V. parahaemolyticus effects on shrimp health and significantly decreased total hemocyte cells, granulocyte cells, and hyaline cells by 30–50% in the period after three days of the challenge, except in L. plantarum treatment, which had only a 20% decrease compared to other treatments. In CNP supplying treatments, the AHPND infected rate and mortality of shrimp were higher than those in other treatments. In summary, the supply of CNP had significantly reduced the shrimp’s immune response and promoted the susceptibility of shrimp to AHPND in both cases of use with and without LAB-containing diets.


2018 ◽  
Vol 7 (11) ◽  
Author(s):  
Sridevi Devadas ◽  
Subha Bhassu ◽  
Tze Chiew Christie Soo ◽  
Fatimah M. Yusoff ◽  
Mohamed Shariff

We sequenced the genome of Vibrio parahaemolyticus strain ST17.P5-S1, isolated from Penaeus vannamei cultured in the east coast of Peninsular Malaysia. The strain contains several antibiotic resistance genes and a plasmid encoding the Photorhabdus insect-related (Pir) toxin-like genes, pirAvp and pirBvp, associated with acute hepatopancreatic necrosis disease (AHPND).


2017 ◽  
Vol 19 (12) ◽  
pp. 1283-1289 ◽  
Author(s):  
Ryohei Suzuki ◽  
Yohei Mochizuki ◽  
Hiroki Yoshimatsu ◽  
Takahiro Teshima ◽  
Hirotaka Matsumoto ◽  
...  

Objectives Hypertrophic cardiomyopathy, a primary disorder of the myocardium, is the most common cardiac disease in cats. However, determination of myocardial deformation with two-dimensional speckle-tracking echocardiography in cats with various stages of hypertrophic cardiomyopathy has not yet been reported. This study was designed to measure quantitatively multidirectional myocardial deformations of cats with hypertrophic cardiomyopathy. Methods Thirty-two client-owned cats with hypertrophic cardiomyopathy and 14 healthy cats serving as controls were enrolled and underwent assessment of myocardial deformation (peak systolic strain and strain rate) in the longitudinal, radial and circumferential directions. Results Longitudinal and radial deformations were reduced in cats with hypertrophic cardiomyopathy, despite normal systolic function determined by conventional echocardiography. Cats with severely symptomatic hypertrophic cardiomyopathy also had lower peak systolic circumferential strain, in addition to longitudinal and radial strain. Conclusions and relevance Longitudinal and radial deformation may be helpful in the diagnosis of hypertrophic cardiomyopathy. Additionally, the lower circumferential deformation in cats with severe hypertrophic cardiomyopathy may contribute to clinical findings of decompensation, and seems to be related to severe cardiac clinical signs. Indices of multidirectional myocardial deformations by two-dimensional speckle-tracking echocardiography may be useful markers and help to distinguish between cats with hypertrophic cardiomyopathy and healthy cats. Additionally, they may provide more detailed assessment of contractile function in cats with hypertrophic cardiomyopathy.


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