Study of possibilities of aquaculture activities in the Gorgan Bay

The Gorgan golf is one of unique ecosystem in Iran which has plenty of known and unknown ecological values. Different agents threaten this ecosystem such as severe exploitation of natural resource on human behalf. This must be restricted using an accepted programs otherwise the ecological situation of the Gorgan golf will be worsen and finally to be died. In these study biological circumstances of the golf has been investigated in order to evaluate its ecological capacity to develop a sustainable aquaculture activities. This study started from Sep, 2010 and lasted to Oct, 2011. On the basis of the results from this study, and with considerations of all environmental conditions some aquatic organisms recommended for aquaculture purposes such as common carp (Cyprinus carpio), Caspian sea salmon (Salmo truta caspius), sturgeons stellate (Acipenser stellatus), Persian sturgeon (Acipenser persicus) and the great sturgeon (Huso huso). The farming procedure recommended as pen culture. In this study, the suitable surface of each pen, required information over each cultured species, suitable density and the amount of catch for each species have been determined. The amount of Nitrogen and Phosphorous originated from feeding and also secreted from fish species as the pollution index entered into the farming sites. The authorized amount of pollution factors for production and aquaculture in the Gorgan golf has been determined. In addition the study over the structure type for farming and also the suitable site for pen culture with consider to the facilities and conditions have been done. With notice to the above, with developing the aquaculture in this ecosystem, local workers will be run and plenty of capital will be invested and finally this will tend to the great revenues by producing of favor protein. This industry is able to change the region to a most important sites to produce aquatic organisms

Study on the reason of striped mullet (Mugil cephalus) larvae mortality and the production of its fingerlings

In this study, nine years old farmed broodstocks of striped grey mullet have been induced artificially by hormones. Eight experiments of artificial propagation carried out during three months (from October to February) in 2003. The hormones used for males were HCG and 17-α-Methyltestosterone and to induce females the hormones such as LHRH-α2, HCG and CPH were used. During these experiments, 27 females injected which 22 of them spawned along with larval production. Water temperature and salinity were 20-23°c and 32 ppt during artificial propagation respectively. For larval culture, two different experiments carried out which final larval density in tanks, water temperature and salinity were 20 in/liter, 22-24°c and 32-33 ppt respectively. Larvae fed with live foods such as Nannochloropsis oculata , Brachionus plicatilis, Artemia nauplii with density of 500000 cell/ml, 20 ind/ml and 3-200 ind/liter respectively. Water exchange in larval culture tanks during first week was 10 percent of tank volume, and this amount in the second and next weeks were higher which have been 2030 and 40-50 percent of tank volume respectively. At the first experiment of larval culture, the tanks with maximum depth of 80 cm used that whole larvae died after 12 days post hatching; whereas at the next trial, three numbers of 4000 liters fiberglass black color tanks with maximum depth of 120 cm used which tend to the survival rate of 0.9 percent after 55 days post hatching

Study on ecological capacity of the release sites of the fingerlings of sturgeon and bony fishes in order to regulate the restocking program at the Gorganrud River

This review is started from April 2002 in Gorgan River and continued for one year. Three sampling stations along the river to the mouth of the estuary were 4000 meters away from the bridge to the village Charqly all samples were collected in this area. Four million sturgeon larvae with average weight of 3/2 grams were obtained from martyr Marjani and Vushmgir Dam farms. Over 40 days released at release stations, and 316 million bony fish fingerlings are being release that 282 million were whitefish, 25 million carp and 9 million bream from Vushmgir Dam and Syjval Bream Center within two months at the release stations in Gorgan River. At sampling stations, especially estuaries to determine the shelf life of fry in the river and to determining migration into the river as well as physical - chemical and assess the frequency and biomass of feeding materials (phytoplankton, zooplankton, and benthos) at the sampling stations in Gorgan River were studied. The entire estuary to the sea makes itself. Maximum migration happened at sunset. Average Debbi for 20-year was at the rate of 14.95 cubic meters per second. In 2002, the annual average was 20.8 cubic meters per second, respectively. Evaluation of abundance and biomass of feeding materials (phytoplankton, zooplankton, and benthos) indicates the status of the average biomass of phytoplankton in the river at the release station was 23/75 mg per liter that was highest in September and was lowest in December. Mean primary production based on a 145 mg chlorophyll cubic meters. 6 orders of benthic invertebrates were observed. Benthic including 9 families and 11 genera have been identified including groups of insects, worms, low-tar and Polychaetes, crustaceans, bivalve and gastropod. But at the release station (S2) the highest levels of benthic biomass (18/18 grams per square meter) degree of diversity of benthic organisms (12) species have largely been seen as a maximum in April and minimum in December. Also zooplankton condition, zooplankton total of 27 genera belonging to five categories, Rotatoria, Kladvsra, Coupe Pvda, Balanvs, and protozoa were identified. In general, in September zooplankton has the greatest diversity and abundance and in September and March, the lowest number is observed

The survey on imported F1 generation carp species in order to enhance genetic diversity of Chinese basic domesticated carp population in Iran

This project has done with the collaboration of Bnyad mostazafan (Ran agriculture and livestock Co.) with goal of increasing efficiency of warm water fishes (Chinese Carps) production. The fish were purchased from China (B. G.) in two parts in Jun 2014. The fish then transferred and quarantined to the ponds in Aghili’s farm In Azadshar using container trucks. The biological parameters of fish such as growth rate were measured during the experiment. The growth rate were obtained 9, 16, 16 and 14% for common carp, big head, silver carp and grass carp, respectively. The result shows that production of experimental ponds (ponds 2 and 4) were obtained 3473 kg/ha while the control ponds produced 2700kg/ha 1n 1393. In general the production were increased 31% when comparing with average of local production and raised 26% when comparing with average production of the entire country in 1393. In this study showed that by importing the F1 generation of Chinese carp, it can expected that production will be increased to 1.5 times of current carrying capacity as long as using aeration system and appropriate management

Investigation on the possibility of artificial propagation, cultivation and brood stock management of Vannamei shrimp

Project was carried out at the Gomishan Centre for training and education which is located 15 km far from Gomishan City in the Golestan Province. Prebroodstocks were chosen from ponds (stocking density: 3/m^2). 860 male and 890 female broodstocks were separated and transferred into greenhouse (400 m^2). The average growth rate per day was 0.3 g and survival rate was 90%. After reaching 42 g in males and 52 g in females they were ready for Eyes stalk Brood stocks were transferred into propagation hall in June and after a week females gone under Eyes stalk. 10,890,000 eggs were yielded from 50 females and consequently 7, 187, 0.50 nauplius were produced. Each broodstock spawned 1.34 Times. The maximum hatching was 75% that in was average 64.2%. Mass of Cetocerous Algae was mass produced to be fed for post larvae. Finally 35,000 PL15 were yielded. PL15 were transferred into two half hectare and one 1 ha ponds in July. The stocking density was 18 PL/m^2. Biometric parameters together with air and water temperatures, and pH were recorded daily. Results indicate that the maximum survival rate was 58% (pond No. 5) and minimum was 52% (pond No. 17). The average weight after 101 days cultivating was 23 g which is appropriate. Also the average daily growth rate was 0.2g and the FCR was 1

Economical study of the grey mullet (Mugil cephalus) culture in the Golestan province

Striped grey mullet (Mugil cephalus) is a marine fish with high commercial value and widespread distribution. The grey mullet and some other mullets can be found in saltwater, brackish and fershwater habitats at tropical, subtropical and also temporal climates.This species is suitable for aquaculture worldwide due to living in wide ranges of water temperatures and salinities, acceptable growth rate, suitable food conversion ratio, marketability, suitable species for polyculture with shrimps, marine fish and even with freshwater carps. The grey mullet is farming in different countries such as Italy, Northern Africa countries ( Egypt), occupied Palestine, India, Pakistan, Japan, Hong Kong, Taiwan, Vietnam, Indonesia, coastal countries of southern pacific ocean and Hawaii. Ten thousands of fries of this species (average weight and length of 280 mg and 28.3 mm respectively) imported in March 2008 from Egypt. The wild fries colleted from surrounding natural waters of Alexandria. After finishing the quarantine steps, they stocked in four earthern ponds (each with 2500 m2) located at the Gomishan shrimp educational centre at late march in 2008. At the first year of culture the densities were 5000 and 10000 individuals per hectar and each treatment with two replicates. At second years densities changed with 2000 and 2500 ind./hec. and each of traetments divided fishes with average primary weights of 80 and 115 grames. The fries and fish feeding begins in April when the water temperature rise above 18 °C and it cut in fall when the temperature goes under 20°C. They fed twice a day at 8 AM and 2 PM and the amount was 5-7 percents of the fish existent biomass in each ponds. They fed with dry formulated feed made of Mahdaneh Karadj Company (Danso dry feed) both the first and second years of farming. The feed prepared for carps feeding and containded 23±2% crude protein, 10±2% crude lipid, about 7% crude fiber, 15 % ash, 40±2% carbohydrates and with energy content of 4000±200 kcal/kg. After seven months culture period the average weight and length of fish in treatment 5000 ind/hec. were 113.7gr and 21.1cm respectively and in treatment 10000 ind./hec. the average weight and length were 86.6 gr and 19.6 cm respectively. At first year the average survival rate in different treatments was 77 percent. The average FCR in treatments 5000 and 10000 ind./hec. were 3.4 and 3.9 respectively. At second years after six months culture the average weights in pond no. 9 (with primary weight 115 gr and density 2000 ind./hec), pond no. 10 (with primary weight 80 gr and density 2000 ind./hec), pond no. 11 (with primary weight 115 gr and density 2500 ind./hec) and pond no. 12 (with primary weight 80 gr and density 2500 ind./hec) calculated as 476.6, 338.1, 366.5 and 440 gr respectively. The average survival rate and FCR were 93 % and 3.1 respectively. Ponds no. 9 and 11 (fish stocked with primary weight 115 gr in densities both 2000 and 2500 ind./hec) selected as the best economic efficient treatments

Study of penculture of the common carp (Cyprinus carpio L.) fingerlings at the Gorgan Bay to the maturity stage (broodstock management)

The aim of present project is study on the possibilities of brood stock production from fingerlings in the penculture condition and the effect of density on it .this project was done during three years with two different treatment and three repetitions in the Gorgan Bay. First treatment with two fingerlings per square meter and the 2nd with four fingerlings per square meter in each pen.To carry out the project at first fingerlings were brought from breeding and recruitment centre –Sijeval (Kolmeh) and the stocked at the earthen pound with concentrated food .After that they were adaptated with brakish water between 7-10 days and transferred to Gorgan Bay for cultivation with average weight of 93.78±32.66 grams and 20.53±2.37 cm in length. It should be noted that 6 pens (which surrounded by nets in the water) were fixed using mast with 15-20 cm in diameter and 5.5 meter in length , Net mesh size was 16 mm with string number 33 of kapron.Feeding was done according to the program two times by giving concentrated food at the period of cultivation Physic -o -chemical factors were measured. biometery was done monthly at each pen and other fishes (unwanted) were observed at the same time. results indicate that in the 1st and 2nd treatments average survival rate was 52.3 and 41 percent respectively with average weight of 410±64.98 grams and 390±52.8 and 28.3±1.79 cm and 27.66±1.57in length. SPSS used to analysethe data such as average length and weight of fish in the treatments and in different months with ANOVA method (p≤ 0.05) . results show that there is no significant difference between treatments. Autopsy observation also showed that fishes (female and male) are mature and histological studies showed that most of observed eggs are entirely mature with 800-1200 micron diameter gonad ( male) were mature at the pen in the Gorgan Bay condition .The male and female hormones were evaluated. 17-B- Estradiol and 11-keto testosterone hormones for adult fish (female and male) parents respectively are similar in dense with those adult fish before injection to use at the artificial breeding. Maturation were verified by autopsy, histology and hormone studies

An investigation on artificial reproduction of Mugil cephalus

Cultured nine years old breeder M. cephalus specimens were subjected to eight artificial breeding treatments from December till February 2003. In treatments 1-5, breeders received two injections of CPH and LIIRFI—A2 coupled with Domperidone or a mixture of CPH and HCG in an interval of 24 hours. Female breeders in treatments 6-8 received a gradual daily injection of 500 1U HCG per kilogram of body weight for 5 days. Male breeders in treatments 6-8 were given 5-10mg of MT-a-17 in addition to HCG and then subjected to two injections similar to that of treatments 1-5. Results showed that male breeders in stages +2 and +3 of all treatments that had received HCG produced more milt than those injected with MT-a-17, such that each male was used 2-6 times for milting purposes. Of 27 female breeders, 22 spawned 1-2.6 million eggs among which eight females' eggs were fertilized 10-95%. Hatching rate was between 0.008 to 88.9% and a maximum of 2 million larvae were produced. The best time for art....

MORTALITY FACTORS IN ARTIFICIALLY REPRODUCED GREY MULLET (MUGIL CEPHALUS L.) FRIES

Cultured nine year old breeders of MugU cephalus L. were subjected to eight artificial propagation treatments from December to February, 2003. Some female breeders received two injections in an interval of 24 hours, and others received a gradual daily injection of 500 IU HCG per kilogram of body weight for five days and then subjected to the two injection protocol. Male breeders were given 5-10mg of 17-a MT in addition to HCG. The result of the process was the production of 117-2000,000 larvae in six series for each breeder. Water temperature and salinity during artificial propagation process were 20-23oC and 32ppt, respectively. For larvae culture two trials were conducted. The final density of larvae was 20 individuals per liter. Water temperature and salinity in larvae culture tanks were 22-24oC and 32-33ppt, respectively. The larvae were fed from their second day post-hatching with algae Nannochloropsis oculata with a density of 500000 cells/l, rotifer Brachionus plicatilis with a density of 20 individuals/ml and also Artemia nauplii with a density of 3-200 individuals/l. The particle size of dry feed used was 100, 300 and 500 microns. The daily water exchange in larval culture tanks at the first, second and third weeks of post- hatching were 10, 20-30 and 40-50 percent respectively. In the first round of larval culture trials which were carried out by means of circular tanks under water 80 cm deep; all larvae died 12 days post-hatching. In the second experiment, which was carried out by three black color fiberglass tanks with water 100 cm deep, the survival rate was 0.9 percent 50 days post-hatching. There are two vertical migrations during first two weeks of the grey mullet larvae culture. The first sinking takes place after the second day post-hatching and is probably related to the rapid absorption of the yolk sac and the resulting change in specific gravity. The second sinking happened 8-11days post-hatching and is probably related to the full absorption of oil globule and the resulting increase in specific gravity. These migrations were found coinciding with high larval mortalities (critical points). It seems that the characteristics of larval culture tank such as shape, volume and depth, the nutritional circumstances of larvae and· the aeration procedure are important and effective factors for the mullet to pass successfully from these critical periods