26 research outputs found
Growth and survival rates, mean weight, food conversion ratio and total harvest in cultured Shrimp Litopenaeus vannamei in Iran
To introduce Litopenaeus vannamei to Iran as a cultured shrimp species, a experimental study was carried out to assess the effects of different stocking densities on growth rate, mean weight, survival rate, food conversion ratio and the total harvest of L. vannamei. Mee post-larval groups (P1,12) of L. vannamei (pond A: 20 PL/m2, pond B: 30 PL/m2 and pond C: 50 PL/m2) with average size 0.9cm and initial mean weight 0.01±0.005g were used in this study. The experiments were carried out in three replications in 9 earthen ponds each half a hectare in size in Khouzestan province, south of Iran during 110 days. The result showed there was no significant correlation (P>0.05) between stocking density and survival rate in the semi intensive culture condition. Mean survival rate among farms were greatest at the lowest density, where mean survival in pond A, B, and C was 88.6%, 83.3%, 73.3%, respectively but the differences were not significant (P>0.05). The results also showed there was no significant relationship (P>0.05) between growth rate and growth days in each experiment. The mean growth rate/days for ponds A, B, and C were calculated at 0.16g/day, 0.16g/day and 0.15g/day, respectively. The food conversion ratio in the end of the study period for ponds A, B and C was 1.01, 1.17 and 1.2, respectively. Shrimp production increased with an increase in stocking density when farm production at Pond A and B indicated a significant difference (P<0.05) compared to that of the pond C. The total shrimp production for ponds A, B and C was calculated at 2803kg/ha, 3146kg/ha and 3972kg/ha, respectively. The water temperature ranged between 28±3°C to 23±3°C, with the highest in July and lowest in September. Salinity ranged between 25±2ppt to 12±3ppt, pH ranged between 8.6±0.2 to 7.50.4 and dissolved oxygen ranged between 5.8± 0.4ppm to 5.3±0.3ppm throughout the study. The study proved that L. vannamei could adapt to common conditions in Iranian shrimp culture environment and also we showed that the species production was higher than the native species already under culture
Identification and characterization of pathogenic viruses in aquatic animal using advanced techniques in order to develop rapid diagnostic kit (shrimp viral disease kit as well as TSV, HPV and MBV )
Shrimp production increasing rapidly in the world and in2013 the production reaches 4.2 MT. In Iran the shrimp production is under development and estimated in 1393, 20 thousand tons produced. In this regards the important subject is health and disease in shrimp farm. The white spot syndrome virus for second time appears in chabahar and damage many farms. Because the aquaculture activity expand in the world in national, regional and international scale, many emerge disease are endanger. In this regard the viral disease is very important and not only decrease the production but also has a side effect in business and national economy. For control and prevention the viral disease, the accurate methods such as PCR kit were developed. In this project the PCR methods with sensitivity, specificity and efficacy was designed and used for detection viral disease. Many viruses have several serotypes and in different area maybe new serotype induce the disease. For this reason, the specific kit will be design. Three viruses consist of MBV, TSV and IHHNV are very pathogenic in shrimp farm and need the specific PCR kit for detection them. In this project the MBV virus was identified and designs a new primer with Oligo software and the primer amplified a part of DNA with 185 bp in the gel. The specificity and sensitivity of primer were checked by IQ2000 Kit and the primer used for detection unknown samples
Epidemiological study on some environmental and management parameters affecting on WSD occurrence in Fenneropenaeus indicus and Penaeus vannamei
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 Hormozganâs 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
Malaria situation in KOhgiloye and Boyerahmad province during 2001-2010
Abstract
Background & aim: Islamic Republic of Iran is one of the well-known foci of malaria in Eastern Mediterranean Region.The study was carried out to investigate malaria situation in Kogiloye and Boyerahmad during during 2001-2010.
Methods: The retrospective study using data information were extracted from health center of archived from malaria cases had been recorded in province during the years of 2001-2010 .The data were analyzed by Descriptive statistical test.
Results: Out of one hundred and fifty six malaria cases during this decade, 119 (76.28%) were males and 37 (23.7%) females. The study showed that about 87% of malaria cases had been occurred in Afghanian immigrants in this region. The highest and lowest (29.6% vs.1.9%) rates of malaria were occurred in 2002 and 2010 , respectively. Among districts of the province the highest rate of malaria cases was belonged to Boyerahmad (80.1%).The present study indicated that Plasmodium vivax was the most common cause of malaria in this region ( 91.02%) followed by P.falciparum ( 8.33%).
Conclusion: During the past decade malaria cases were apparently decreased in Kohgiloye and Boyerahmad province and most of cases had been imported to the region from other endemic foci. Respect to suitable environmental conditions for transmission of malaria in this area surveillance measures should be implicated to control disease through rapid diagnosis and treatment of patients particularly in foreign immigrants.
Key words: Malaria, P.Vivax , P.Falciparu