4 research outputs found

    Investigation of two crop culture of western white shrimp

    Get PDF
    Two crop culture of western white shrimp with 2 treatments and 2 replicates in each treatments in earthen ponds with area 0.4 hectares at a density of 20 pl 18 in each square meter were done. For the culture of shrimp in the second stage, the post larvae cultured in nursery pond with area of 0.25 hectare, and density of 96 post larvae in each square meter, and then transfer to the rearing ponds. In each pond, 2 aerators with potency of 3 horsepower fixed. Every day horsepower clarified at 21p.m. to 23 p.m and out at 6 a.m to 7 a.m. The first stage of culture begun in 19 April with pl 18. The yield pick-up after 96 days. The stocking of pl in the nursery ponds was done in 25 July with pl16 and after 38 days hunted and transferred to second stage culture. The second culture was done in 1 September and pick-up after 65 days. For feeding of shrimps we used commercial food numbers 4001 until 4006. In the first mount the feeding of shrimps were done as blind feed and then with the shrimps biomass and with research of feeding trays. Water temperature, dissolved oxygen and pH daily in 2 times at the morning (6 a.m) and evening (at 15 p.m) and the salinity, transparency and water depth 1 time daily measured. In the first culture period (96 days), the mean weight, length, daily weight gain, FCR, survival percent shrimp production were 14.03 gr, 12.08 cm, 0.15 gr, 1.02 gr, 92 percent and 2132 kilograms and in the second culture period (65 days) 14.55 gr, 12.48 cm, 0.22 gr, 0.84, 73 percent and 2675 kilogarms measuered respectively. Totally, in the second period culture the initial weight of shrimps was higher than the first period culture 1.95 gr and 0.008 gr respectively, therefore growth indexes in the second period were better than the first culture period. Coefficient of determination of weight and lenth of shrimps with increase of cultue days, in the first and second culture periods, in the total cases the number were higher than 0.97. This shown that the role of increase of days on the increase of weight and lenth is higher than 97 percent. Also, determination of product moment, showed that there is very strong correlation between increase of days and increase of weight and lenth and between weight and lenth (0.97 to 0.99)

    Impact assessment of master plan of "attain to technical knowledge of specific pathogen free shrimp production and cut off to dependence on foreign products" on Bushehr city environment: A case study, Shoghab research station

    Get PDF
    This study is a part of the national and technology master plan entitled "Attain to technical knowledge of specific pathogen free shrimp production and cut off to dependence on foreign products". The goals of this work were to assess the environmental effects of Specific Pathogen Free shrimp production complex on surrounded region in Persian Gulf (Shoghab) research station in Bushehr city. The environmental impacts were assessed in Persian Gulf (Shoghab) research station in Bushehr city by usage of simple checklist for impacts prediction, and scaling check list for assessment during Feb 2012 till Sep 2014. Flushing the effluents to the sea is the biggest concern of this project that can resulted in health impacts on aquatic and human communities that can be avoided by treatment. Low diversity in activities beside lack of environmental sensitive elements in the region leads us to use of scaling check list for impact assessment. Environmental grade of each activity can be achieved by stratification of them according to their intensity, significance and scale. We reached +320 and -198 for positive and negative points respectively that sounds a clear yes for execution choice

    Evaluation growths and survival indexes of vaccinated Litopenaeus vannamei against white spot virus syndrome

    Get PDF
    Nowadays, white spot virus disease is serious threat for breeding and culture industry of shrimp. In this study was increasing resistance of shrimp against white spot virus by using modern methods such as shrimp vaccination with inactivated viruses and recombinant proteins. The aim of this study were determine the growth and survival rates vaccinated and non-vaccinated of Litopenaeus vannamei (5 to 15 and 12 to 26 day), that were challenged with white spot virus in 40 and 60 day rearing. This study consisted two separate groups were vaccinated and non-vaccinated with 11 treatments experimental and each of replicate was stocked 1000 pieces by post larva of 5 to15 and 12 to 26 day. After vaccination, two groups of post larvae exposed to the white spot virus at 40 and 60 day, one groups no exposure to the virus. Samplings were randomly of shrimp in 40, 60 and 80 days 10 pieces each of treatment experimental and measured mean of weight and length. Also, number of deaths was recorded at morning and evening daily and calculated survival rate at the end of study. The results showed growth rate of post larvae vaccinated (5 to15 day) which exposed to white spot virus at 40 and 60 was significantly lower than non-vaccinated of post larval, while the growth rate of post larval exposed to virus in 60 day was significantly increased. On the other hand, growth rate of post larval vaccination (12 to 26 day) exposed to virus in 60 day compared with post larval vaccination (5 to 15 and 12 to 26) exposed to virus in 40 and 60 days was significantly increased. Hence, growth rate was significantly increased in post larval vaccinated (5 to 15 and 12 to 26) which non-exposed to virus. Although the survival rate was post larval vaccinated (12 to 26 days) exposed to virus Post larvae in 60 day higher than post larval were exposed to virus in 40 and 60, but no significant differences were observed. However, relative mortality of post larval vaccination in 12 to 26 day compared with post larval vaccination in 5 to 15 days exposed to virus were significantly lower. Considering growth and survival index was improved of post larval vaccination can be concluded that the optimum age for vaccination against white spot virus of L.vannamei was 12 to 26 day

    Standardization of insurance operations and risk assessment and edition of manual for recognition of management and natural disaster risks in shrimp farms, and feasibility study of insuring shrimp hatcheries

    Get PDF
    According to achieve sustainable production in shrimp farming industry, it is necessary to provide the relief of producers through insurance. Aquaculture faces various environmental conditions such as unpredictable climate changes, epidemic diseases, harsh water factors, that may affect the production cycle, and impact on producer's life. In this research, the effects of various factors on production of cultured shrimp have been studied. The project conducted through completion of questionaries by random selected of small scale farms, and all large farms which engaged in production in that years. In order to increase the accuracy of responses, special questionnaires provided to fill in by expertise experts. All data explained the share of management and natural factors on production process
    corecore