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Decline in capture fisheries and sea food demand lead to improve shrimp aquaculture activities. Iran had good experiences on shrimp farming during tow decades. White spot disease collapse the shrimp farming activities in recent years. Although goater were the main site for shrimp culture but this site were affected by white spot disease (WSD). Environmental stressors were the main criteria for attention in this regard. An investigation was carried out to monitor management practices and to find out whether there is any relationship with occurrence of white spot disease and environmental parameters. Five semi-intensive shrimp farms were selected in bahookalat chabahar area (2500 ha). The farms were situated at goater area. Tree ponds from each farm at random were selected for the study. All major environmental parameters such as O2, temperature, salinity. PH, nitrogen were recognized by standard method. Logistic regression were used for relationship of water parameters with occurrence of white spot disease. There were no significant relationship between PH, salinity and nitrogen in ponds and canals. But significant variations were recorded for oxygen (1.58) Temperature (0.89) with occurrence of white spot disease. Pond aeration can use for reduction and prevention of diseases.

For the first time white spot disease (WSD) was reported in shrimp farms of khoozestan province, in southwest of IRAN in 2002. Then in 2005 the neighbor province, boushehr, was contaminated. In 2008 WSD outbreak reported in sistan-bloochestan province in southeast of Iran. In 2015 all of southern shrimp farms of country except Hormozgan, the middle southern province, which has remained free of WSD, are being contaminated. White Spot disease suspended shrimp culture in thousands hectares of shrimp farms. Considering that white spot disease has not been observed in Hormozgan province yet, the question is; to what extent environmental and management factors participated in preventing WSD outbreak or cause WSD outbreak. In this study (20102012), the effects of environmental factors and management, stressors that decrease immune system function of shrimp are discussed. In addition, the role of pathogen as the main factor of outbreak is discussed. The goal of this study is to define environmental parameters and management practices associates with outbreak of white spot disease in affected provinces and discover reasons of being Hormozgan province free of this disease. In this study the role of the local environmental factors and management practice stressors in susceptibility to WSD was determine. Both the effects of environmental factors in water of ponds including total ammonia, nitrogen, dissolved oxygen, pH, salinity, transparency, and temperature and management issues related to biosecurity are studied. There were overlaps on physical and chemical parameter values obtained in clear areas with contaminated areas .Results of the data analysis suggest that lack of association with WSD incidence was 7 times greater than WSD incidence despite of disease outbreak in sistan-bloochestan province, so other sources of white spot disease virus incidence was suspected in affected areas. Histopathological examinations and polymerase chain reaction (PCR) tests during project performance did not reveal white spot disease virus evidences in post larvae examined from khoozestan province stocked in farms but disease outbreak was happened in that farms , so we suspected to management practice include feed , pond preparation and carrier of disease . Recorded values of temperature and salinity in some months during inspection in Hormozgan province specified stressful condition that may lead to WSD outbreak, however the disease did not appear. Therefore the hypothesis that the water physical and chemical conditions are reasons to prevent disease outbreak in Hormozgan province is being rejected. The policy of Hormozgan’s fishery authorities, to replaced Fenneropenaeus indicus with specific pathogen free Litopenaeus vannamei, that is more resistant to some of diseases, before incidence of WSD in farms and to before being endemic in the Hormozgan province, made an advantage compare to affected southern provinces that introduced Litopenaeus vannamei after WSD prevalence to their farms. However it does not guarantee to maintain current trend of being Hormozgan province farms free of white spot disease. Therefore establishing the principals of biosecurity are strongly emphasized. Strategies taken by the proficient authorities in preparation of SPF shrimp broodstock can be the most important factor in preventing WSD. Regarding biosecurity principals purchased feed must be free of shrimp head powder. Construction the new shrimp farms should be as far as it could be away from contaminated areas. Iranian Fisheries Science Research Institute Published

Decline in capture fisheries and sea food demand lead to improve shrimp aquaculture activities. There are valuable capacities for shrimp culture in Guater site in Chabahar which could be mentioned as making employment. White spot disease collapses the shrimp farming activities in recent years. Although Guater were the main site for shrimp culture but this site were affected by white spot disease (WSD). Environmental stressors were the main criteria for attention in this regard. An investigation was carried out to monitor management practices and to find out whether there is any relationship with occurrence of white spot disease and environmental parameters. Desirable climate fluctuation happened in monsoon seasons in Guater area parallel with shrimp culture. Evidence of thermal shock beside presence of pathogens makes suitable condition for evidence of disease. Therefor one of the most important embarks is reducing the risk of this accident by selecting suitable time for post larvae stocking. Based on our study the best time for this purpose in Guater site is from March to June .Other recommended footsteps in relation to reduce outbreaks are: settlement bio security, using immune system simulators, embrace SPF brood stocks.

Decline in capture fisheries and sea food demand lead to improve shrimp aquaculture activities. Iran had good experiences on shrimp farming during tow decades. White spot disease collapse the shrimp farming activities in recent years. Although goater were the main site for shrimp culture but this site were affected by white spot disease (WSD). Environmental stressors were the main criteria for attention in this regard. An investigation was carried out to monitor management practices and to find out whether there is any relationship with occurrence of white spot disease and environmental parameters. Five semi-intensive shrimp farms were selected in bahookalat chabahar area (2500 ha). The farms were situated at goater area. Tree ponds from each farm at random were selected for the study. All major environmental parameters such as O2, temperature, salinity. PH, nitrogen were recognized by standard method. Logistic regression were used for relationship of water parameters with occurrence of white spot disease. There were no significant relationship between PH, salinity and nitrogen in ponds and canals. But significant variations were recorded for oxygen (1.58) Temperature (0.89) with occurrence of white spot disease. Pond aeration can use for reduction and prevention of diseases. Iranian Fisheries Science Research Institute Published

Decline in capture fisheries and sea food demand lead to improve shrimp aquaculture activities. There are valuable capacities for shrimp culture in Guater site in Chabahar which could be mentioned as making employment. White spot disease collapses the shrimp farming activities in recent years. Although Guater were the main site for shrimp culture but this site were affected by white spot disease (WSD). Environmental stressors were the main criteria for attention in this regard. An investigation was carried out to monitor management practices and to find out whether there is any relationship with occurrence of white spot disease and environmental parameters. Desirable climate fluctuation happened in monsoon seasons in Guater area parallel with shrimp culture. Evidence of thermal shock beside presence of pathogens makes suitable condition for evidence of disease.Therefor one of the most important embarks is reducing the risk of this accident by selecting suitable time for post larvae stocking. Based on our study the best time for this purpose in Guater site is from March to June .Other recommended footsteps in relation to reduce outbreaks are : settlement biosecurity , using immune system stimulators , embrace SPF brood stocks. Iranian Fisheries Science Research Institute Published

For the first time white spot disease (WSD) was reported in shrimp farms of khoozestan province, in southwest of IRAN in 2002. Then in 2005 the neighbor province, boushehr, was contaminated. In 2008 WSD outbreak reported in sistan-bloochestan province in southeast of Iran. In 2015 all of southern shrimp farms of country except Hormozgan, the middle southern province, which has remained free of WSD, are being contaminated. White Spot disease suspended shrimp culture in thousands hectares of shrimp farms. Considering that white spot disease has not been observed in Hormozgan province yet, the question is; to what extent environmental and management factors participated in preventing WSD outbreak or cause WSD outbreak. In this study (20102012), the effects of environmental factors and management, stressors that decrease immune system function of shrimp are discussed. In addition, the role of pathogen as the main factor of outbreak is discussed. The goal of this study is to define environmental parameters and management practices associates with outbreak of white spot disease in affected provinces and discover reasons of being Hormozgan province free of this disease. In this study the role of the local environmental factors and management practice stressors in susceptibility to WSD was determine. Both the effects of environmental factors in water of ponds including total ammonia, nitrogen, dissolved oxygen, pH, salinity, transparency, and temperature and management issues related to biosecurity are studied. There were overlaps on physical and chemical parameter values obtained in clear areas with contaminated areas .Results of the data analysis suggest that lack of association with WSD incidence was 7 times greater than WSD incidence despite of disease outbreak in sistan-bloochestan province, so other sources of white spot disease virus incidence was suspected in affected areas. Histopathological examinations and polymerase chain reaction (PCR) tests during project performance did not reveal white spot disease virus evidences in post larvae examined from khoozestan province stocked in farms but disease outbreak was happened in that farms , so we suspected to management practice include feed , pond preparation and carrier of disease. Recorded values of temperature and salinity in some months during inspection in Hormozgan province specified stressful condition that may lead to WSD outbreak, however the disease did not appear. Therefore the hypothesis that the water physical and chemical conditions are reasons to prevent disease outbreak in Hormozgan province is being rejected. The policy of Hormozgan’s fishery authorities, to replaced Fenneropenaeus indicus with specific pathogen free Litopenaeus vannamei, that is more resistant to some of diseases, before incidence of WSD in farms and to before being endemic in the Hormozgan province, made an advantage compare to affected southern provinces that introduced Litopenaeus vannamei after WSD prevalence to their farms. However it does not guarantee to maintain current trend of being Hormozgan province farms free of white spot disease. Therefore establishing the principals of biosecurity are strongly emphasized. Strategies taken by the proficient authorities in preparation of SPF shrimp broodstock can be the most important factor in preventing WSD. Regarding biosecurity principals purchased feed must be free of shrimp head powder. Construction the new shrimp farms should be as far as it could be away from contaminated areas.

In this study two species of algae, Sargassum glaucescens and Padina boergeseni that found plenteously in Persian Gulf and Bushehr coast, were collected and hot water extracts of them were lyophilized. F. indicus (11.32±1.20 g), after two weeks adaptation in Shoghab research station were immersed in seawater (39 ppt and 25±1 ○C) containing hot-water extract of each brown algae, S.glaucescens and P.boergeseni, at 100, 300 and 500 mg/l concentration, Survival rate and immunological parameters (total haemocyte count (THC), total plasma protein (TPP), Phagocytic activity, bacterial clearance efficiency and bactericidal activity) were examined. In addition effect of dietary administration of beta 1, 3 1, 6 glucan on prevention of White Spot Disease and immunological parameters of shrimp were investigated. According to results, immersion in seawater containing 300 and 500 mg/l concentration of algal hot-water extract after 2 and 3 hours or oral administration of beta 1,3 1,6 glucan at level of 10 g/kg diet for 14 days significantly enhanced THC, TPP, Phagocytic activity, bacterial clearance efficiency and bactericidal activity. Immersion in seawater containing 100, 300 and 500 mg/l hot-water extract of S.glaucescens after 3 hours, improved the survival rate of WSSV-infected F. indicus.

In this study two species of algae, Sargassum glaucescens and Padina boergeseni that found plenteously in Persian Gulf and Bushehr coast, were collected and hot water extracts of them were lyophilized. F. indicus (11.32±1.20 g), after two weeks adaptation in Shoghab research station were immersed in seawater (39 ppt and 25±1 ○C) containing hot-water extract of each brown algae, S.glaucescens and P.boergeseni, at 100, 300 and 500 mg/l concentration, Survival rate and immunological parameters (total haemocyte count (THC), total plasma protein (TPP), Phagocytic activity, bacterial clearance efficiency and bactericidal activity) were examined. In addition effect of dietary administration of beta 1, 3 1, 6 glucan on prevention of White Spot Disease and immunological parameters of shrimp were investigated. According to results, immersion in seawater containing 300 and 500 mg/l concentration of algal hot-water extract after 2 and 3 hours or oral administration of beta 1,3 1,6 glucan at level of 10 g/kg diet for 14 days significantly enhanced THC, TPP, Phagocytic activity, bacterial clearance efficiency and bactericidal activity. Immersion in seawater containing 100, 300 and 500 mg/l hot-water extract of S.glaucescens after 3 hours, improved the survival rate of WSSV-infected F. indicus. Iranian Fisheries Science Research Institute Published

The WSD is the important viral shrimp disease in past decade. The detection of virus in each country was investigated by polymerase chain reaction for sensitivity and accurate. In this research study we collected 23 samples from shrimp suspected to WSD. The DNA from samples collected and extracted and design two kind of primer from VP24 identified in gene bank by DNAsis software. A primer also designs for House keeping gene for positive and negative samples in all examined. The results showed the gene colon for wssv is the similar with others and 97% is consistency. The product of PCR was colon in plasmid and confirmed and this plasmid used for internal control. Iranian Fisheries Science Research Institute Published

The WSD is the important viral shrimp disease in past decade. The detection of virus in each country was investigated by polymerase chain reaction for sensitivity and accurate. In this research study we collected 23 samples from shrimp suspected to WSD. The DNA from samples collected and extracted and design two kind of primer from VP24 identified in gene bank by DNAsis software. A primer also designs for Housekeeping gene for positive and negative samples in all examined. The results showed the gene colon for wssv is the similar with others and 97% is consistency. The product of PCR was colon in plasmid and confirmed and this plasmid used for internal control.