NEW TECHNOLOGIES IN AQUACULTURE DEVELOPMENT (JOURNAL OF FISHERIES)
Year:2012 | Volume:6 | Issue:3 (23)|Papers Count:15

This study was performed in 1999. A series of 4 cruises were conducted by R/V Ferdows 1. The studied area was from Meidani (58o 55 E) to Gwatre Bay (61o 30 E) having depths of 10 to 100 m. and divided in to 5 sub regions (A, B, C, D, and E) from west to east which had 30 minutes longitude. Each region was divided in to 4 depth stratum: 10-20, 20-30, 30-50 and 50-100 m. The area of each layer was estimated by plan meter. In each cruises, sampling was carried out for more than 90 stations using a bottom trawler for 1 hours, the following measurements were carried out. Length frequency, length- weight relationship and biomass of 3 fish species of Perciformes such as Pomadasys kaakan, Pampus argenteus and Nemipterus japonicas were estimated by separate depth layers and the studied area. Furthermore, the animal geography distribution of all 3 species were determined, seasonally. The annual biomass of mentioned species was 2413.77, 241.41 and 1263.58 tons, respectively.

Marzanabad reservoir is located in Mazandaran province, south-western part of Babol. Its area is 183 hectares and its mean depth is 2.5 meters. This reservoir is rich in aquatic plants and has been a good habitat for migratory birds. The entrance of farmland wastewaters and pollutants are from the impacts leading to a loading of DIN and TP into this reservoir. This study was conducted in order to trophic status in this ecosystem for the first time during 1 year since September 2006 to August 2007. In this research, water temperature, dissolved oxygen, pH, trophic state indicators including TP, Chla, Secchi depth and dissolved Nitrate concentration was studied based on the Carlson trophic state index in 3 stations with 3 replicates monthly. According to TSI, Marzanabad reservoir is in eu-hypereutrophic condition.

The present study evaluated the effects of ice delaying on the quality of banana shrimp (Panaeus merguiensis). Two groups of shrimp selected for this purpose. First group (A) immediately iced and second group (B) iced after two hours of catching. Sensorial and microstructure changes of shrimps were measured during a period of 20 days. Sensory, chemical, and microbial indexes are usually used for quality assessment during storage period. The study of changes in fish and shrimp microstructures is one of the important and new indexes for deterioration assessment. Increasing of extra-cellular space and fiber shrinking was observed as time of storage increased. After 8 days of storage, it was very difficult to recognize the muscle fibres in the delayed iced samples, while disintegration of myofibrils in the immediately samples observed after 12 days of storage. Results also showed that 2hrs delay in icing shorts shelf life of shrimp up to 4 days as compared with immediately icing samples. Moisture content, protein, fat and ash of group A were 74.76, 21.35, 1.45 and 1.66, respectively, in the first day, and reached to 81.33, 15.6 1.33 and 0.81 after twenty days, while these amount in group B were 74.94, 21.72, 1.36 and 1.91 respectively, at the first day, and reached to 81.62, 15.26, 1.09 and 0.82 at the end day of storage. However, it was observed significant difference between moisture content, protein and ash in the first and last storage day in two groups (P<0.05) but there was not significant difference between fat content (P>0.05). From the results, it can be suggested that delayed icing decreases shrimp quality up to 4 days.

In this study, growth indices of Acipenser persicus at the Shahid Marjani (S.M.) Center and Voshmgir Reservoir (V.R.), for releasing purpose in Gorganrud River, was investigated in 2002. The area for cultivating A. persicus at S.M. was 14 ha, the number of cultured A. persicus 1120000 pieces, the number of released was 429930 pieces and survival rate was calculated 38.4%, in 2002. Also, the mentioned parameters for V.R. were 102 ha; the number of cultured was 11135000, the number of released 41795116 and survival rate 37.53%. The length and weight of fingerlings in S.M. were in range 7.2-15 cm, 2.2-12.6 gr and mean weight 4.69±0.69 gr, also in V.R. were in range 6-9.3 cm, 1.08-3.1 gr and mean weight 2.5±0.22 gr. Condition factor and growth rate in S.M. were 0.43±0.02 and 5.31±0.4, respectively, and these parameters were 0.41±0.02 and 5.5±0.4 in V.R. The results of this study showed that condition factor and growth rate of fingerlings revealed no significant variation in S.M and V.R. (P>0.05).

This study was conducted in the Delvar Aquaculture complex during February 2009 to December 2010. The microphones and microphones of 6 pounds in 2 farms were counted and identified, monthly. The environmental factors, salinity, dissolved oxygen and climatic conditions were recorded. Results were showed, polychaeta, gastropoda and bivalva (macrofauna) were dominant and the most frequency of mayofauna was in June and July. Pond bottom organic matter (TOM) was minimum in June and maximum in September, respectively. The extent of sediment aggregation was from. 5 mm to less than 63 mm and the percentage of particles smaller than. 63 mm formed 75-90% of pond sediments during second half period of shrimp culture. The average production rate and the average food consumption in1.2 hectares of farm 2 was more at about 2812.8 kg in the area of 1.2, and also the average food consumption in this farm in the area of 1.2 hectare has been 5688.2 kg more than farm 1; and there was a significant difference between 2 farms in the average production rate and food consumption rate.

Mnemiopsis Leidyi (Ctenophora), is the naïve of Atlantic coast (North and South America). The appearance of this kind of pectinated animals was reported at once in 2008 in the southern coasts of Caspian Sea that was entered via Black sea from its motherland by balance water of ships. Intense reduction of Kylka stocks, sturgeons and Caspian seal in the Caspian Sea is associated with the widespread distribution of these Ctenophora. According to authorized Kylka fishing, just increasing of the number of vessels and their fishing are not sufficient reasons for reducing of kylka stocks, but this factor with invasion and presence of the ctenophore in the years of 1998 to 2009 are caused the reduction of the amount of Kylka stocks and fishing. Subsequent to this reduction, from 2003, the mitigation plan of vessel number and natural restoring of the sea too, fishing of Kylka has improved so that in the end of February 2009 in comparing to 2008 has been increased 68% than in 2008.

In this study, three practical diets containing three levels of digestible energy 300, 370 and 450 Kcal/100g and 30% crude protein for rearing of Astacus leptodactylus was prepared. Effects of these diets were determined on growth index, survival and body composition. In this experiment, it used three treatments each had three repetitions. The crayfish rearing was done for 60 days in 9 fiberglass tank with 110-liters capacity. Average of initial weight of the crayfish was 17±2.3g. Results indicate the highest SGR, PER, NPU, WG. Survival and protein of body composition occurred in the diet with 370 kcal/100 g energy which has no significant difference.

Common carp (Cyprinus carpio), endemic of the Caspian Sea, allocated high catch rate in Golestan province. Due to the significance of its commercial importance, preservation and restoration of this fish will be seem necessity by artificial breeding. Sperm quality is scaling to assessment the ability of fertilizing achivement. So, the sperm quality biomarkers such as (spermatocrit, sperm density, pH, Osmolarity, seminal plasma composition, etc.) that directly affect on sperm fertilizing ability, must be specified.34 pieces of Common carp broodstock was catched from Gorgan rood river beach and then,sperm collection was done by low pressure on side of the abdomen and were collected by 2-ml syringe.To assess plasma components, semen of each broodstock by use of refrigerated centrifuged with 1500 rpm for 25 min centrifuged and plasma was separated and stored at -20oC respectively. Sodium, potassium, calcium, magnesium, glucose, total protein, cholesterol and urea were determined by spectrophotometry and special kits. The values of some parameters such as spermatocrit and protein had no a lot of changes, while other parameters had a lot of changes. Some of biochemical parameters of carp semen (except spermatocrit, iron, calcium, and cholesterol) have no significantly different at various ages. With increasing age of the fish, iron and calcium levels increased in some age groups, the increase was significant. The ratio between the ions in most cases have no significant different at various ages, but had no regular decrease or increase. Spermatocrit with magnesium ion, sodium, potassium, iron, cholesterol, and triglyceride levels had significant different and positively correlation and with the other parameters had no significant different.ion correlation was measured. This study and determine the Common carp sperm quality parameters can improve the efficiency of artificial propagation.

In this study, the aquatic and semi aquatic plants in channels of agriculture and aquaculture of Khuzestan province were identified during 2008-2009. In the area, 55 species belonging to 36 genera and 26 families were identified. In total channels of agriculture and aquaculture of Khuzestan Province Ceratophyllum demersum and Najas minor (submerged species) were observed. In North Khuzestan, Dezful-Shush, Ceratophyllum and Potamogeton were the largest genus. Between Shush–Ahvaz Polygonum hydropiper and Phragmites australis were the highest diversity in this area. The South of Khuzestan, Phragmites australis, Cyperus pygmaeus and Typha australis, three emerged aquatic plans, were the most dominant species though related to the international wetland of Shadegan. In East-South Khuzestan (Mahshahr Port-Hendijan), Phragmites australis and Lemna gibba were the largest genus. Chorologically, 29% of species were Iran-Turanin. The largest of biotic spectrum of this area was consisted of Hydrophyte (24%).

This study aimed to determine water quality characteristics, correlation between changes in water quality and shrimp growth and determination the growth model of the shrimp (Litopenaeus vannamei) during one production cycle in Gomishan region (Golestan province). Nine water quality variables include temperature, salinity, transparency, pH, NO3, NH4, P2O5, H2S, and PO4 were measured in shrimp pond according to standard methods. Based on results obtained during the period, salinity increased, transparency reduced, pH were not significant and temperature decreased in the final weeks. The results showed that the mean values of PO4 and P2O5 in perceptions had significantly different but other factors had not significant. The regression analysis showed among the various factors in the growth model, PO4 into the growth model. The correlation results between shrimp production and chemical characteristic of water showed, production was associated with higher levels phosphorus.

At first microalgae (Scenedesmus sp.) was collected by plankton net (20 microns), samples from Khazarabad area (This research was performed by Caspian research group of fisheries and water pollutants). Samples were transferred into laboratory, isolated and purification by Pipette Pasture method. After the medium culture was made, the stoke of above green algae with primary culture density (7×106 cells/ml) was inoculated to medium culture at 25±2 temperature and 3500±350 LUX light density. This experiment was carried out for the study of growth. In this experiment, it was taken account 2 treatments and 3 replicates. The observation microalga was carried out by light microscope (40X). The tool of counting was utilized by Hemcytometer slide (for five grade samples counting). In addition the number of colony was separately counted. The average counting of colony in medium culture (TMRL&Z-8+N) constitutes five stage which were obtained 6.06×106±1.47×106 and 21.70×106±1.39×106, respectively. The average of single-cell colony with 53.5% and for cell colonies with 39.7% have the most colony growth that was attributed to TMRL and Z-8+N, respectively. The growth rate and growth coefficient was specially measured. These indices in TMRL & Z-8+N were 0.52 and 0.26, respectively. For comparison, the growth value of above algae was used nonparametric Kroskal-wallis test for total counting, as it showed that there is significant difference from first to five counting in Z-8+N (P=0.009) and TMRL(P=0.027). But the test of Mann-Whitney had no significant difference about 2 medium cultures (P=0.065). Generally, the comparison of 2 medium cultures was shown that the efficacy of Z-8+N medium culture was higher than TMRL medium culture for microalgae growth Scenedesmus in laboratory condition.

Cyprinus carpio L., 1758 is one of the economic value species of Caspian sea. Nowadays, for conservation and restocking of this species artificial propagation methods is considered. Thus study of some of biological characters is needed. In these study 165 individuals of fishes examined for record of biometric data and age determination. Male fish’s length and weight ranges were 253-660ml and 265-3670 gr, respectively. Also female fish’s length and weight ranges were 305-602ml and 310-2900 gr, respectively. Age rane of all brooders were 2-14 years. Absolute fecundity ranges were calculated 77447-430745 eggs. Decreasing of age groups and aged individuals of brooders may be related to unsuitable reproduction and feeding conditions of their habitats and overfishing, thus fisheries management on the southern coastal waters of Caspian sea is necessary.

Fish transportation and oxygenation are the subjects that can significantly affect the fish survival and growth after transportation. Recently, Hydrogen peroxide used instead of the Malachite Green as a disinfector but considering its positive role in the oxygenation it can be propose to use for the juveniles transportation. In this way it is necessary to determine the optimum concentrations its function in the short time and fish physiological changes and water quality during transportation. In this study, Oxygenation effect of H2O2 and oxygen capsules in two different treatments was compared. Each treatment included four replicates (45 fish per tank) both for hydrogen peroxide and oxygen capsule. Four plastic cones contain 4 CC H2O2 per liter of water added to 1 gr. grass carp liver as catalyzer to exhaust oxygen. Produced oxygen transferred to tanks via tubes. Fish samples were beaded in 0, 3 and 6 hours intervals in both groups. Results of this study showed that using of the hydrogen peroxide has no negative effect on the hematological parameters such as lymphocyte monocyte, neutrophil, eosinophil, MCHC, HCT, Hb, RBC, MCV, MCH and stress indices including Glucose and Cortisol. Water chemical quality factors include NH4, NO3, NO2 decreased meanwhile using hydrogen peroxide in tanks. Considering low price of H2O2 and increasing demand for short time fish transport and the costs of oxygen capsules and its heavy weight and with a look to importance of fish health during transport operation the proposed method has potential to apply as appropriate way in small scale fish transport.

In one annual survey from 2006 (March-April) to 2007 (April-May) we collected 12 female broodstocks of Kutum with average length (46.69 cm) and weight (835.83gr) and 18 male broodstocks of Kutum with average length (45.26cm) and weight (817.22gr) in 3 groups of broods (3+, 4+ and 5+ years old) the migration time to Tajan river ( Mazndaran province) by passive catch. Blood samples were collected from the fish after biometry had been done. Blood was taken using a syringe from peduncle vein and poured into vials containing Heparin (anti-clotting of blood). Hematological parameters in blood samples were measured following laboratory standards methods. The results showed that most blood factor related to R.B.C Count (1181333.30) and lowest in Mon (0.73). Surveying the results of hematological male and female breedstocks showed significant difference in Mon (P<0.05) but did not have in R.B.C Count, W.B.C Count, H.C.T, Hb, M.C.V, M.C.H, Lym, Neu (P>0.05). The results showed that among age groups had significant difference in Neu (P<0.05) but did not have in R.B.C Count, W.B.C Count, H.C.T, Hb, M.C.V, M.C.H, Lym, Mon (P>0.05).