Journal of Aquaculture Development
Year:2014 | Volume:8 | Issue:2|Papers Count:9

The presence of heavy metals; copper (Cu), lead (Pb), cadmium (Cd) and zinc (Zn) in water was monitored during different stages of breeding and rearing of Acipenser persicus at the Shahid Beheshti Sturgeon Hatchery during the period of use (April-May) of these pesticides in the study region. Water samples were collected (3 samples from each point) from the main pond, Kurenski pond, incubators, Vniro tanks, earthen ponds and at the river estuary where fingerlings are released into the sea. Heavy metal concentrations in water samples were determined using Atomic Absorption Spectrophotometer FAAS-Varian AA-220. Highest concentrations of heavy metals belonged to the element Zn (36.0±3.6 ppb) which was determined in the water sample collected from the inlet of master pond. Lowest concentration for Zn recorded was 0.98±0.26 ppb. Highest concentration for Cu was 10.5±1.18 ppb and the lowest concentration for this element was 0.65±0.26 ppb. The highest and lowest concentrations recorded for lead were 9.33±1.19 and 0.15±0.01 ppb, respectively, while those for cadmium were 0.116±0.019 and 0.016±0.003 ppb, respectively. The results obtained indicate the presence heavy metals studied in the water samples although they were lower than the maximum permissible concentration for these pollutants for the breeding and rearing of Acipenser persicus in sturgeon hatcheries.

This study aimed to comparative study of sargassum and canola meals as protein sources and determines the best replacement ratio in growing of white-leg shrimp (Litopenaeus vannamei). Since, juvenile shrimp with an average initial weight of 6.2±0.3g was performed from Jask hatchery and transferred to Off- Shore Research Center- Chabahar using standard method. After one week adaptation, eight experiment diets, all iso-nitrogenus (33% protein) and iso-caloric(3450 Kcal. 100 g-1 Dry weight of feed, each with 3 replicates including control (no canola and no sargassum meals), four treatment levels of 25, 50 and 75 and 100 percent of canola cake meal and 3 treatment levels of 5, 10 and 15% sargassum meal, were given 240 shrimp which they introduced to 24 plastic tank( 300 L.), 4 times per day, 8 am and 12, 16 and 29 pm, The average water temperature 29.60±0.60oC and salinity of 33±0.8 g.L-1. At the beginning of culture period, the feed were given based on 3% of BW and then ad libitum, growth parameters and survival rates were measured at 10 days interval. At the end of experiment, meantime measuring of biometrical parameters of all shrimps, 3 shrimps from each replicate were moved to laboratory to colorimetric, cholesterol determination and Caracas analysis. The results showed that even 100% canola and 15% sargassum meals can be replace as protein sources of shrimp diets without any adverse effect on growth and survival performances and there are not any differences between growth and survival rates of shrimp statistically (P<0.05). The diets containing sargassum meal specifically 15% changed shrimp color to pink and reduced the cholesterol shrimp content statistically (P<0.05), while the diets containing canola meals cannot The highest protein content were measured in Caracas shrimp of control group statistically while there are not any differences between treatments shrimp Caracas proteins statistically (P>0.05).

In order to determine optimum dietary protein and lipid levels on growth performance of hybrid female Asp × male Kutum (Aspius aspius ♀×Rutilus frisii ♂), six trial diets containing three protein levels (30, 35 and 40%), and two lipid levels (10 and 15%) were designed. In the present study, Two hundred and fifty two fish with initial weight of 31.22±0.38 g (mean±SE) were distributed in 18 tanks with the volume of 4000 L and were fed 3 times daily for 60 days. The results indicated that growth performance and feed conversion ratio was significantly affected by protein content of the diet, so that these parameters increased significantly with increasing protein level from 30% to 35%, and then decreased in 40% (P<0.05). Growth performance was not affected by dietary lipid (P>0.05). The highest values of condition factor was observed in fish fed diets containing 35% protein and 15% lipid (P<0.05). Protein efficiency ratio decreased with increasing dietary protein level (P<0.05), so that the lowest values of PER were observed in diets containing 40% protein at each lipid levels. Lipid efficiency ratio was significantly decreased with increasing dietary lipid level (P<0.05). In general, the results indicated that diet containing 35% protein and 15% lipid is suitable for the optimum growth of this hybrid in the studied weight range.

The study was done in nutrition and live food in aquaculture research station was located in Bandar Anzali- Ghaziyan. Juveniles weighted average of kutum 0.5, 1, 2.5 gr were randomly selected in three groups Caspian Sea with a salinity of 11 ppt, water 7 ppt and freshwater (with three replicates per group) were included. To study the microstructure of gill for each treatment, tissue samples by classical histological methods and stained with hematoxylin - eosin slides were prepared. The frequency and location of the enzyme Na+, K+- ATPase and chloride cells with immunohistochemical localization was performed. Studies micrometric gill chloride cells by software Image tool (version 2.0) was performed. Gill chloride cell counting results showed that in every square millimeter of surface gill tissue 0.5, 1 and 2.5 g juveniles, 9000, 9000-10000, 10070-12060 chloride cells there respectively. Overall, the results of measuring ions and osmotic pressure on the tenth day of treatment, the osmotic potential juveniles 2.5 gr in Caspian sea water and all groups except the juveniles 0.5 gr in water of 7 ppt confirmed.

This study was conducted to assess the impacts of a commercial prebiotic, Bionic yeast cell wall, on growth, nutritional factors, survival rates and intestinal bacterial flora of rainbow trout fingerlings (average weight 12±1g) in a completely randomized design consisting of 0, 1, 2, and 3 grams of the prebiotic per kg of basal diet. The results indicate a significant increase in specific growth rate (SGR), body weight, condition factor (CF) and protein efficiency in treatments were fed Bionic yeast cell wall (p<0.05) and FCR in the prebiotic treatments decreased compared to the control treatment which the difference between 2g prebiotic treatment and control was significant (p<0.05). At the end of the experiment there was no significant difference in survival rate between all treatments (p>0.05). Results showed that different levels of the prebiotic increase lactobacillus counts in fingerlings intestine significantly (p<0.05) where the total number of bacteria remained constant. According to the research the prebiotic can be a dietary supplement for rainbow trout fingerlings and 2 gram per kilogram of food is recommended as optimal dose.

Alumniosilicat crystalline zeolite composition with pore structure can be absorb the water hydrate ion and other cat ions. This matter improves the ion capacity transportation in three dimensional charts of Sio2 and Alo4 and freely mention. The smallest sizes of pores (5Angestrom) with in suspension solution colloidal structure have the most contact by outside environment. Also nanosilver zeolite has the more stagnant connection than other nano particles solution, have the best efficiency on antibacterial, antiviral and antifungal features from aquaculture environment. Due to small number of study about edible use of nano zeolite in fish diet current research investigating the dietary usage of nanosilver zeolite in Rainbow trout diet with initial weight (5±0.5 gr) and (6±0.7 cm) length in 9 (180×120×70cm) aquarium on Average of daily growth rate (ADG), Special growth rate (SGR), food concentration ratio(FCR), condition of fat (CF), Protein efficiency ratio (PER), survival rate (SR) and Carcass quality index in three examine treatment(zero, two and three percentage nano silver zeolite) mixed in Biomar commercial diet by providing 1.5 mm and 1.9 mm pellets for 40 days. At last statistical treatments analysis showed; there is significant difference in ADG and CF indexes between evidence treatment and two percentage of nanosilver zeolit in diet(p<0.05). Also showed these differ in (Rainbow trout) survival rate between control group and four percentage of nanosilver zeolite in diet. Between second and third treatments for amount of Protein Efficiency Ratio (PER) shows this difference too (p<0.05) while in there were high difference between other treatments and control group (P<0.01). Carcass analyses quality and quantities comparison showed the high amount of protein and low amount of fat from (5-15 gr) fish in evidence treatment. So on four percent of nanosilver zeolite in diet to achieved the best quality of Carcass in upper weights. Generally the survey results illustrated that none used of the nano technological matter in fry rainbow trout diet is suitable.

Recently using growth stimulators in fish diets has been brought to attention. Among these supplements, using medicinal herbs as a growth and immune system stimulator has been paid more attention to, due to their lower damage rate to fish and environment. The aim of this study is to evaluate the effect of parsley (Petroselinum sativum) as a growth stimulating dietary supplement in diet of Koi (Cyprinus carpio) on growth parameters, feed conversion ratio and survival rate. 180 specimens with the average weight of 0.93±0.22 g were fed diets supplemented with four concentrations (0.1, 0.25, 0.5 and 1 percent) of parsley and the control group were fed with a parsley-free diet for 60 days. During the study period, the fish were biologically surveyed every 15 days. Growth and feeding indices and survival rate were measured. Fishes that were fed with diets supplemented with parsley showed better growth, FCR and survival rate. The highest weight gain (2.36±0.16 g), length gain (2.83±0.76 cm), specific growth rate for weight (3.93±0.18) and Specific Growth Rate for length (4.72±0.79), the least feed conversion ratio (1.34±0.19)) and also the most daily growth rate (3.9±0.29) belonged to the treatment containing 0.5 percent parsley in the diet and these differences were significant in comparison to the control group (p<0.05). It can be concluded that 0.5 percent parsley can be used in Koi dietary feed as a good growth stimulator.

The main purpose of this study was to investigate the application level of new technologies among trout fish farmers of Guilan Province. The present study was of applied and conducted with descriptive method by using questionnaire. Statistical population of this research contained of all 170 managers of trout fish farms of Guilan province that 97 of them were chosen as a sample to fill questionnaires. Content and face validity of research tool was obtained by a panel of experts. To obtain reliability of questionnaires, Cronbach’s a coefficient was used (0.70). The results show that 86.6 percent of trout fish farmers, Use at least one of aquatic beast growing technologies. Results of t-test and F-tests showed that there is a meaningful difference in use of technology in terms of rate of study, source of water, farm capacity and use of loan. Rate of using weathering technologies, biotechnology and structure engineering have had the most usage and physical filter technologies, food production and UV antiseptic case have had the least usage among Guilan’s trout fish farmers. As well, no use of fodder devices and automatic cleaners was seen. Results for investigation of usage level of technologies showed that most of growers (57.1%) have been in level of average acceptance and have used five to ten technologies in their farms.

This study was conducted to evaluate adaptation and maturity trend of Iranian Cichlid (Iranocichla hormuzensis) fish in captivity. Sixty three fish were collected from their natural habitat, Shahoo River (between Bandar Abbas and Haji Abad) and were moved to High Tech Fisheries Research Station- Khojir- IFRO. The fish were then divided into 9 groups based on weight (5-7 fish per group), and were placed in aquariums (100×40×40 cm3) fixed on iron shelves. During the two month experiment, all the environmental parameters were monitored and maintained within the standard ranges. Feeding was performed manually based on 3% BW. At this stage, reproduction behavior and changes in secondary sex characteristics such darkening color pigmentation especially in the male fish were monitored weekly. The obtained results showed that this native ornamental fish can well adapt to the captivity condition and successfully pass through the sexual gland development and maturity stages during the two month experiment.