Publication Date:
2021-05-19
Description:
Whiteleg shrimp (Litopenaeus Vannamei) is one of the most important species for aquaculture development, because of tolerance and adaptation to different ecological conditions.The aim of this study was determine the bionormative parameters of vannamei shrimp culture using Caspian Sea brakish water in Mazandaran province and also possibility of introduction a new aquatic spciese for rereaing in Mazandaran province. The Shrimp vannamei reared with the brackish water (10±0.43ppt) of the Caspian Sea in Mazandaran province and the Caspian Sea Ecological Research Iinstitute in summer 1391, 1393 and 1394. In this study, were evaluated the effect of different densities (45/m2, 50/m2, 55/m2 and 60/m2) primary stock whiteleg shrimp postlarvae (PL12) on the growth, survival rate and also population structure of phytoplankton in shrimp vannamei. Initially, post larvae in brackish water were gradually adopted. The density of 35 per square pieces in an earthen pond (1000m2) was stocking.The rearing time was 85 days. Average daily growths: 0.31±0.037g; final mean weight: 21.11±0.71; Feed conversion ratio: 0.79 and final yield: 531kg were determined. In addition the experiment of 1391, the results of Mazandaran province vannamei shrimp culture, were observed in 1393 and 1394, the average weight average daily growing and FCR % were 20-18 g and 0.68 - 0.77 respectively during 90 days culture period with harvesting of 40 PL /m2 at cement culture pond. The experiments of effect of different densities were performed separately in 1391, in 12 circular concrete pound with a sandy bed (area: 78m2) in the four treatments and three replications for each treatment. The experiments performed in a 75-day period. During the test, the water temperature was 27.4±1.79°C. The results showed that growth parameters and survival rate in experimental treatments, there was a statistically different (Duncan test, P〈0.05). Thus, with high levels of density, the amount of weight gain and survival rate (SR), specific growth rate (SGR) and daily growth rate (ADG) has decreased. In addition, the treatments were different variations of FCR (P〈0.05) and not depend on the primary stock density of postlarvae. The highest growth (SGR=11±0.04 and ADG=0.25±0.01) and survival rate and calculate the amount of production per hectare (5596±433) were observed in low density (45m2). In this study identified 20 genera of phytoplankton from five division of the Phytoplankton. Phylum Cyanophyta, with 30 percent of the identified genera that much more constituted. And the phylum Chlorophyta with 25 percent, of Bacillariophyta 20 percent Pyrrophyta 20 percent and Euglenophyta 5 percent had the lowest frequency. Chlorophyta with 25 percent allocated to the division, with 20 percent of Bacillariophyta, with 20 percent of the division; Pyrrophyta Euglenophyta division with 5 percent had the lowest frequency.Euglenophyta phylum was identified as a species. Therefore, based on acquired results, was observred that, vannamie shrimp was reared well using Caspian Sea brakish water in Mazandaran province. In addition, it seems that, vannamei shrimp was gained better results in Mazandaran province compared to other provinces, because of suitable water salinity.
Description:
Iranian Fisheries Science Research Institute
Description:
Published
Keywords:
Vannamei shrimp
;
Brackish water
;
Saline water
;
Culture
;
Shrimp
;
Litopenaeus vannamei
;
Aquaculture
;
Stock density
Repository Name:
AquaDocs
Type:
Report
,
Refereed
Format:
58pp.
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