Papers by aghil dashtiannasab
Iranian Journal of Fisheries Sciences, Oct 10, 2012
During the last decade, shrimp aquaculture has developed rapidly in many developing countries. An... more During the last decade, shrimp aquaculture has developed rapidly in many developing countries. Antibiotic resistance is a major problem in shrimp aquaculture. Seaweeds are considered as potent source of bioactive compounds that are able to produce biological activities. The aim of this study was to evaluate the antibacterial activity of ethanolic and chloroformic crude extracts of the brown algae, Sargassum latifolium derived from Persian Gulf waters. The extractions against shrimp selective pathogen bacteria including Vibrio alginolyticus, V. parahaemolyticus and V. harveyi were used by disk diffusion agar method. Results revealed that all mentioned bacteria were sensitive to both ethanolic and chloroformic crude extracts of S.latifolium. The minimum inhibitory concentration of chloroformic extract of S. latifolium against the bacteria was performed by tube dilution technique. MICs were 5, 10 and 10 mg ml-1 for V. alginolyticus, V. parahaemolyticus and V. harveyi, respectively while minimum bactericidal concentrations (MBC) were 5, 15 and 20 mg ml-1. This study recommended that S.latifolium isolated from Persian Gulf waters has antibacterial activity potential against shrimp pathogen bacteria.
Harmful Algae, 2020
Harmful algal blooms (HABs) have had harmful effects on the health of a wide range of organisms a... more Harmful algal blooms (HABs) have had harmful effects on the health of a wide range of organisms and are becoming a noteworthy risk to fisheries, human health and wildlife around the globe. Although the lethal influences of dinoflagellate Margalefidinium / Cochlodinium polykrikoides have been well-documented for finfish, the impacts on decapod crustacean species, especially, Litopenaeus vannamei are poorly understood. Here, we examined the exposure of L. vannamei juveniles with different M. polykrikoides densities (T1: 1 × 10 3 , T2: 2 × 10 3 , T3: 3 × 10 3 , T4: 9 × 10 3 and T5: 30 × 10 3 cells ml −1), in order to observe possible histological alterations in gills and hepatopancreas. After 96 h exposure, shrimp exhibited increased mortality and survival rate of juveniles in control group were meaningfully (P < 0.05) higher than treatments exposed to 9 × 10 3 and 30 × 10 3 cells ml −1 of M. polykrikoides. The lowest survival observed in treatments T4 (95.56%) and T5 (82.20 %), respectively. The juveniles exposed to high densities of M. polykrikoides had flaccid bodies and gills were yellow in color with some black spots (melanization) in pereiopods. At the end of the experiment, shrimps' hepatopancreas and gills exhibited various histological alterations. The irregular appearance of the tubular structure of the hepatopancreas, R-and B-cells reduction, separation of epithelium and myoepithelial layer, ruptured epithelial cells and degeneration of tubules were detected in the hepatopancreas of shrimps exposed to 30 × 10 3 cells ml −1. In gills of shrimp exposed to 30 × 10 3 cells ml −1 , alterations in epithelial structure, increases in the number of intercellular hemocytes, and changes in tissue structure were observed. Finally, findings suggest that M. polykrikoides blooms can lead to significant impacts on survival and major histological alterations in gills and hepatopancreas organs when the density of M. polykrikoides was over 9 × 10 3 cells ml −1 .
White Spot Disease (WSD) is a important disease due to economic impacts in shrimp industries. Spr... more White Spot Disease (WSD) is a important disease due to economic impacts in shrimp industries. Spreading of this disease in shrimp farms can caused a 100% mortality during 3-10 days. Therefore control of this disease is a strategy in shrimp industry. Vaccination is a way to control of WSD. In several years ago during a project several type vaccine of this virus by association of Atomic Energy Organization is produced that among of them the virus inactivated by GAMA radiation had better results in laboratory. To test of this vaccine in field, a research pilot was carried out. Initially 20000 shrimp napliies were obtained from one of commercial hatchery in Bushehr province, then devided to two groups vaccinated and unvaccinated. The vaccinated group also devided . 26and PL12 , group B vaccinated at PL15and PL 5to two groups, group A that vaccinated at postlarva e (PL) Rrsults showed that difference of growth performance and survival rate between vaccinated and unvaccinated without chal...
Shrimp aquaculture has developed rapidly in 1980s decade and this development caused to increase ... more Shrimp aquaculture has developed rapidly in 1980s decade and this development caused to increase shrimp diseases in farms. In the last 0f 1980s and first of 1990s find of health shrimp Postlarvae for stocking was hard. In Iran also after two decades diseases are the main problems, then a national project (Shrimp SPF production) was performed that this section was monitoring and identification of viral pathogens in that project. For this propose selected shrimps in farms was sampled and screened for main viruses (OIE list), shrimps without infection bring to quarantine system for one month and in the end of quarantine period were screened again. Then in winter spending, before and after spawning, it’s offspring in F1 and F2 also screened for viral pathogens by IQ2000 kit in Iranian veterinary organization lab. Moreover all shrimp feeds in clouding: fresh feed, live feed and pellet feed had been screened for OIE viral pathogens listed for three years. Results of viruses screening in s...
White Spot Virus (WSV) is currently the most serious viral pathogen of shrimp worldwide; it cause... more White Spot Virus (WSV) is currently the most serious viral pathogen of shrimp worldwide; it causes mortality up to 100% within 7-10 days in commercial shrimp farms. Infected Indian white shrimp Fenneropenaeus indicus samples were collected from Guatr shrimp site in Sistan and Baluchestan province in south of Iran and WSV infection was confirmed by Nested PCR. WSV was isolated from infected shrimp samples by centrifugation and filtration and multiplied in crayfish by intramuscular inoculation, the isolated virus was called WSV/IRN/1/2010. In order to determine the dilution resulting in 90-100% mortality in Penaeus semiculcatus, diluted virus stock in steps from 10 0 till 10 5 times in sterile PBS was injected intramuscularly to 14 shrimps in each group. Also the virus stock was diluted in steps from 1/2 till 1/32 times in sterile PBS and injected intramuscularly in Astacus leptodactylus crayfish. Therefore the LD 50 of live virus stock in Astacus leptodactylus and Penaeus semiculcatus crayfish were calculated by the Karber method 10 3.29 /ml and 10 5.35 /ml, respectively.
The first time the white spot disease (WSD) and IHHNV were reported in Iran was in 2004 and 2008,... more The first time the white spot disease (WSD) and IHHNV were reported in Iran was in 2004 and 2008, respectively in Bushehr Province. In Sistan and Balochestan province only the WSD was reported in 2008.The aim of this study was detecting these two viral diseases in these provinces, during December 2009 to April 2010. A total of 364 samples were collected according to suspected gross signs from hatcheries and shrimp farms in Bushehr and Sistan and Blochestan provinces (I.R. Iran) respectively, including larvae (72, 43 samples), post larvae (48, 37 samples), juveniles (57, 32 samples), sub adults (39, 22 samples) and broodstock (29, 13 samples) of Litopenaus vannamei . WSD was detected from juveniles (23 samples), sub adults (14 samples), and broodstock (14 samples), and IHHNV was also detected from juveniles (16 samples), sub adults (9 samples) and broodstock (5 samples) based on gross signs, PCR and histopathological changes from Bushehr province but from Sistan and Blochestan provin...
Chinese Journal of Oceanology and Limnology, 2014
ABSTRACT The present study was conducted to investigate the effect of gamma irradiation on white ... more ABSTRACT The present study was conducted to investigate the effect of gamma irradiation on white spot syndrome virus (WSSV). White spot syndrome virus is a pathogen of major economic importance in cultured penaeid shrimp industries. White spot disease can cause mortalities reaching 100% within 3-10 days of gross signs appearing. During the period of culture, immunostimulant agents and vaccines may provide potential methods to protect shrimps from opportunistic and pathogenic microrganisms. In this study, firstly, WSSV was isolated from infected shrimp and then multiplied in crayfish. WSSV was purified from the infected crayfish haemolymph by sucrose gradient and confirmed by transmission electron microscopy. In vivo virus titration was performed in shrimp, Penaeus semisulcatus. The LD50 of live virus stock was calculated 10 (5.4)/mL. Shrimp post-larvae (1-2 g) were treated with gamma-irradiated (different doses) WSSV (10(0) to 10(-4) dilutions) for a period of 10 days. The dose/survival curve for irradiated and un-irradiated WSSV was drawn; the optimum dose range for inactivation of WSSV and unaltered antigenicity was obtained 14-15 kGy. This preliminary information suggests that shrimp appear to benefit from treatment with gammairradiated WSSV especially at 14-15 KGy.
Iranian Journal of Fisheries Sciences, 2017
Bacterial diseases have been reported to be the major limiting factor in shrimp production. The u... more Bacterial diseases have been reported to be the major limiting factor in shrimp production. The use of natural products such as antimicrobials has been reported as a solution to the problem. The crude extract of a red seaweed Laurencia snyderiae obtained from the Persian Gulf was evaluated for shrimp growth performance and to determine in vivo efficacy of this seaweed in the prevention of shrimp Vibriosis. The ethanol extract from L. snyderiae (EELS) that was fed to the Artemia instar I for their enrichment was found to be non toxic to them. Shrimp Litopenaeus vannamei juveniles were fed with these enriched Artemia at 0 mg mL (Control group), 200 mg mL, 400 mg mL and 600 mg mL for 30 days. The results obtained showed a significant increase (p<0.05) in survival rate in treatment groups compared with that in the control group. Shrimps fed with enriched Artemia showed a significant improvement in growth parameters when compared to those in the control group. When these juvenile shri...
Since the shrimp aquaculture as a commercial activity initiated in the 1970s, diseases had emerge... more Since the shrimp aquaculture as a commercial activity initiated in the 1970s, diseases had emerged as major problems in farmed shrimp. By the emergence of white spot syndrome virus (WSSV) in the first of 1990s, this virus covered all diseases and shadowed other shrimp diseases. White spot syndrome disease is a contagious, high virulent, and pandemic disease of crustaceans especially shrimps caused by WSSV. Since the emergence of WSSV in China in 1992, the virus spread quickly to all the major shrimp aquaculture in both east and west hemisphere countries. The virus belongs to genus Whispovirus in the family Nimaviridae with a rod-shaped double-stranded DNA. This virus is known to cause severe diseases infecting shrimps, which leads to high mortality and huge socioeconomic impacts. The most clinical signs are redness of body coloration and appendages, reduction of feeding, lethargy, and characteristic of white spots on the carapace. The modes of transmission of WSSV in the natural env...
The use of antibiotics in aquaculture has been limited. Scientifics seeking for natural substitut... more The use of antibiotics in aquaculture has been limited. Scientifics seeking for natural substitutes to prevent of aquatic animals diseases. Considering seaweeds are rich of nutritions and bioactive compounds, the purpose of this study is: investigation the potential and use possibility of native seaweeds from Persian Gulf in shrimp aquculture industry to improve growth, survival of postlarvae and to resistance against pathogens such as vibriosis. For this propose 7 macroalgae species from Bushehr province coast, inclouding: green algae (C. iyengarii), brown algae (S. angutifolium and S. ilicifolium) and red algae (L. snyderiae, K. alvarezii and G. corticata) were collected and identified. Then seaweed extracts abtained by Water, Ethanol, Methanol and Chloroform solvents by soaking method. In vitro antibacterial activity of extracts against Gr+ bacteria (S. aureus and B. subtilis) and Gr- bacteria (V. harveyi, V. alginolyticus and E. coli) was conducted by Agar diffusion, MIC and MBC...
Fish & Shellfish Immunology
Aquaculture has been an important role in human's food production during the past 100 years. ... more Aquaculture has been an important role in human's food production during the past 100 years. By growing the population, demand for seafood also increased that this demand couldn't come from fisheries. So aquaculture has expanded rapidly in recent decade. Aquaculture now is an economic industry in many countries. Shrimp aquaculture is also expanded since 1970 and it has provided employment and been a main driver of socio-economic development in poor rural and coastal communities, particularly in Asia. However, the rapid growth of aquaculture has also been the source of ecological changes on an enormous scale. Aquatic animals have been displaced from their natural environment, reared in high density, exposed to many stress conditions, provided artificial or unnatural feeds, and a plentiful global trade has developed in both live aquatic animals and their products. According to these reasons aquaculture practices provide an ideal environment for emergence and spread of diseases...
During the last decade, shrimp aquaculture has developed rapidly in many developing countries. An... more During the last decade, shrimp aquaculture has developed rapidly in many developing countries. Antibiotic resistance is a major problem in shrimp aquaculture. Seaweeds are considered as potent source of bioactive compounds that are able to produce biological activities. The aim of this study was to evaluate the antibacterial activity of ethanolic and chloroformic crude extracts of the brown algae, Sargassum latifolium derived from Persian Gulf waters. The extractions against shrimp selective pathogen bacteria including Vibrio alginolyticus, V. parahaemolyticus and V. harveyi were used by disk diffusion agar method. Results revealed that all mentioned bacteria were sensitive to both ethanolic and chloroformic crude extracts of S.latifolium. The minimum inhibitory concentration of chloroformic extract of S. latifolium against the bacteria was performed by tube dilution technique. MICs were 5, 10 and 10 mg ml-1 for V. alginolyticus, V. parahaemolyticus and V. harveyi, respectively while minimum bactericidal concentrations (MBC) were 5, 15 and 20 mg ml-1. This study recommended that S.latifolium isolated from Persian Gulf waters has antibacterial activity potential against shrimp pathogen bacteria.
White Spot Virus (WSV) is currently the most serious viral pathogen of shrimp worldwide; it cause... more White Spot Virus (WSV) is currently the most serious viral pathogen of shrimp worldwide; it causes mortality up to 100% within 7-10 days in commercial shrimp farms. Infected Indian white shrimp Fenneropenaeus indicus samples were collected from Guatr shrimp site in Sistan and Baluchestan province in south of Iran and WSV infection was confirmed by Nested PCR. WSV was isolated from infected shrimp samples by centrifugation and filtration and multiplied in crayfish by intramuscular inoculation, the isolated virus was called WSV/IRN/1/2010. In order to determine the dilution resulting in 90-100% mortality in Penaeus semiculcatus, diluted virus stock in steps from 10 0 till 10 5 times in sterile PBS was injected intramuscularly to 14 shrimps in each group. Also the virus stock was diluted in steps from 1/2 till 1/32 times in sterile PBS and injected intramuscularly in Astacus leptodactylus crayfish. Therefore the LD 50 of live virus stock in Astacus leptodactylus and Penaeus semiculcatus crayfish were calculated by the Karber method 10 3.29 /ml and 10 5.35 /ml, respectively.
Crustaceans have a short life and assumed lesser intricacy,
but have bene¢cial mechanisms to dete... more Crustaceans have a short life and assumed lesser intricacy,
but have bene¢cial mechanisms to detect foreign
matter. They appear to recognize common
components in bacteria and fungi, such as b-glucans
and lipopolysaccharides. Haemocytes in crustaceans
play important roles in the host immune response including
recognition, phagocytosis, melanization, cytotoxicity
and cell^cell communication. Several
quantitative procedures are being designed to evaluate
the activation of the immunity in shrimp.With regard
to cellular parameters, the total haemocyte
count (THC) and haemogram have been considered
to be potential markers. Concerning humoral parameters,
the antibacterial activity of plasma and the
concentration of plasma proteins can be considered
as criteria of health status (Sanchez, Pascual, Vargas-
Albores, Le Moullac & Rosas 2001).
Bacterial diseases have been reported to be the major limiting factor in shrimp production. The u... more Bacterial diseases have been reported to be the major limiting factor in shrimp production. The use of natural products such as antimicrobials has been reported as a solution to the problem. The crude extract of a red seaweed Laurencia snyderiae obtained from the Persian Gulf was evaluated for shrimp growth performance and to determine in vivo efficacy of this seaweed in the prevention of shrimp Vibriosis. The ethanol extract from L. snyderiae (EELS) that was fed to the Artemia instar I for their enrichment was found to be non toxic to them. Shrimp Litopenaeus vannamei juveniles were fed with these enriched Artemia at 0 mg mL-1 (Control group), 200 mg mL-1 , 400 mg mL-1 and 600 mg mL-1 for 30 days. The results obtained showed a significant increase (p<0.05) in survival rate in treatment groups compared with that in the control group. Shrimps fed with enriched Artemia showed a significant improvement in growth parameters when compared to those in the control group. When these juvenile shrimps were exposed to Vibrio harveyi (after 30 days) they showed notably lower mortality than the control. These results indicate that EELS has a good potential in promoting growth and antibacterial activities against V. harveyi that is useful in shrimp aquaculture.
The first time the white spot disease (WSD) and IHHNV were reported in Iran was in 2004
and 200... more The first time the white spot disease (WSD) and IHHNV were reported in Iran was in 2004
and 2008, respectively in Bushehr Province. In Sistan and Balochestan province only the
WSD was reported in 2008.The aim of this study was detecting these two viral diseases in
these provinces, during December 2009 to April 2010. A total of 364 samples were collected
according to suspected gross signs from hatcheries and shrimp farms in Bushehr and Sistan
and Blochestan provinces (I.R. Iran) respectively, including larvae (72, 43 samples), post
larvae (48, 37 samples), juveniles (57, 32 samples), sub adults (39, 22 samples) and
broodstock (29, 13 samples) of Litopenaus vannamei . WSD was detected from juveniles (23
samples), sub adults (14 samples), and broodstock (14 samples), and IHHNV was also
detected from juveniles (16 samples), sub adults (9 samples) and broodstock (5 samples)
based on gross signs, PCR and histopathological changes from Bushehr province but from
Sistan and Blochestan province only WSD was detected from juveniles (26 samples), sub
adults (18 samples) and broodstock (7 samples). Histopathological observations of WSSV
showed basophilic Cowdry type A inclusion bodies in all tissues such as gills, haematopoietic
tissue, cuticle epithelium, lymphoid organ and connective tissue. However histologically, the
hepatopancreas tissue showed vacuolization of B cells, without inclusion bodies, but
histopatholgical changes caused by IHHNV including eosinophilic Cowdry type A inclusion
bodies which were ectodermal, mesodermal and rarely endodermal.
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Papers by aghil dashtiannasab
but have bene¢cial mechanisms to detect foreign
matter. They appear to recognize common
components in bacteria and fungi, such as b-glucans
and lipopolysaccharides. Haemocytes in crustaceans
play important roles in the host immune response including
recognition, phagocytosis, melanization, cytotoxicity
and cell^cell communication. Several
quantitative procedures are being designed to evaluate
the activation of the immunity in shrimp.With regard
to cellular parameters, the total haemocyte
count (THC) and haemogram have been considered
to be potential markers. Concerning humoral parameters,
the antibacterial activity of plasma and the
concentration of plasma proteins can be considered
as criteria of health status (Sanchez, Pascual, Vargas-
Albores, Le Moullac & Rosas 2001).
and 2008, respectively in Bushehr Province. In Sistan and Balochestan province only the
WSD was reported in 2008.The aim of this study was detecting these two viral diseases in
these provinces, during December 2009 to April 2010. A total of 364 samples were collected
according to suspected gross signs from hatcheries and shrimp farms in Bushehr and Sistan
and Blochestan provinces (I.R. Iran) respectively, including larvae (72, 43 samples), post
larvae (48, 37 samples), juveniles (57, 32 samples), sub adults (39, 22 samples) and
broodstock (29, 13 samples) of Litopenaus vannamei . WSD was detected from juveniles (23
samples), sub adults (14 samples), and broodstock (14 samples), and IHHNV was also
detected from juveniles (16 samples), sub adults (9 samples) and broodstock (5 samples)
based on gross signs, PCR and histopathological changes from Bushehr province but from
Sistan and Blochestan province only WSD was detected from juveniles (26 samples), sub
adults (18 samples) and broodstock (7 samples). Histopathological observations of WSSV
showed basophilic Cowdry type A inclusion bodies in all tissues such as gills, haematopoietic
tissue, cuticle epithelium, lymphoid organ and connective tissue. However histologically, the
hepatopancreas tissue showed vacuolization of B cells, without inclusion bodies, but
histopatholgical changes caused by IHHNV including eosinophilic Cowdry type A inclusion
bodies which were ectodermal, mesodermal and rarely endodermal.
but have bene¢cial mechanisms to detect foreign
matter. They appear to recognize common
components in bacteria and fungi, such as b-glucans
and lipopolysaccharides. Haemocytes in crustaceans
play important roles in the host immune response including
recognition, phagocytosis, melanization, cytotoxicity
and cell^cell communication. Several
quantitative procedures are being designed to evaluate
the activation of the immunity in shrimp.With regard
to cellular parameters, the total haemocyte
count (THC) and haemogram have been considered
to be potential markers. Concerning humoral parameters,
the antibacterial activity of plasma and the
concentration of plasma proteins can be considered
as criteria of health status (Sanchez, Pascual, Vargas-
Albores, Le Moullac & Rosas 2001).
and 2008, respectively in Bushehr Province. In Sistan and Balochestan province only the
WSD was reported in 2008.The aim of this study was detecting these two viral diseases in
these provinces, during December 2009 to April 2010. A total of 364 samples were collected
according to suspected gross signs from hatcheries and shrimp farms in Bushehr and Sistan
and Blochestan provinces (I.R. Iran) respectively, including larvae (72, 43 samples), post
larvae (48, 37 samples), juveniles (57, 32 samples), sub adults (39, 22 samples) and
broodstock (29, 13 samples) of Litopenaus vannamei . WSD was detected from juveniles (23
samples), sub adults (14 samples), and broodstock (14 samples), and IHHNV was also
detected from juveniles (16 samples), sub adults (9 samples) and broodstock (5 samples)
based on gross signs, PCR and histopathological changes from Bushehr province but from
Sistan and Blochestan province only WSD was detected from juveniles (26 samples), sub
adults (18 samples) and broodstock (7 samples). Histopathological observations of WSSV
showed basophilic Cowdry type A inclusion bodies in all tissues such as gills, haematopoietic
tissue, cuticle epithelium, lymphoid organ and connective tissue. However histologically, the
hepatopancreas tissue showed vacuolization of B cells, without inclusion bodies, but
histopatholgical changes caused by IHHNV including eosinophilic Cowdry type A inclusion
bodies which were ectodermal, mesodermal and rarely endodermal.