This study was conducted to provide procedures for increasing the productivity and profitability of sturgeon culture in Iran. We designed a questionnaire covering economic and ecologic aspects of the activity and distributed it to an expert team comprised economists, statisticians and aquaculturist experts. The team completed the questionnaires to determine the costs of production of a single sturgeon FINGERLING in Iran, considering all sturgeon centers. Also, documents available in different sections of Iranian Fisheries, specially, accounting, budgeting and stock enhancement offices were resorted to. Cost of labour comprised 55% of expenditures whereas costs of feeding and fertilizer were found to be 14%. The maintenance cost was assessed as 7% and fertilized eggs cost was 6%. Results showed that on average, the production cost of a single sturgeon FINGERLING in Iran in the year 2000 was 992 Rls. Among all of the sturgeon breeding centers in Iran, Shahid Rajaee Aquaculture center had the lowest cost of production with 477 Rls., while Shahid Beheshty center had the highest cost amounting to 1224 Rls. The cost of labour has a large share in total expenditures, somewhat caused by the center not being active for six months each year. Tasking the labour force with other activities might reduce the total costs in such hatcheries.

In this experiment, the FINGERLINGs of grass carp reared under natural feeding of the pond were allowed to observe carp attacks on fully floating (pieces of bread) and sinking food (laboratory –made pellet). The performance and feeding starting times were then compared among carp-exposed or carp-observer grass carp that could see the food directly with the demonstrators’ foraging activity and naïve grass carp groups that couldn't see the demonstrators’ (common carp) feeding activity. The carp-exposed and carp-observer groups of grass carp were better at feeding reaction (start time) than naïve fish when they fed on two novel fully floating and sinking food. When they fed on floating bread, 80% of the chambers of grass carp with carp in compare with 53% of the chambers with only naïve grass showed starting taking food for the duration of 5 days. When they fed on sinking pellets, 65% of the carp - observer grass carp in the tanks compared with 20% of the chambers with the naïve grass carps, showed taking the diet for the duration of 5 days. More carp-exposed grass carp learned taking novel floating diet during 10 days experimental period and the observer grass carp in the experimental tanks with sinking novel diet showed catching pellets 48 hour before the naïve grass carp groups. The FINGERLINGs of carp-exposed and carp-observing grass carp were capable of direct observational learning in their feeding behavior.

Sparidentexhasta is a beneficial and economical fish in the Persian Gulf that these years much attention has been paid to and is a good candidate for marine aquaculture in coastal zones of Iran. Optimal levels of dietary components ensure optimum growth and health of fish. In this paper, feeding the Sparidentexhasta with different levels of protein and amino acidwas carried out in order to investigate their effects on hematological parameters. After adaptation in 2 weeks by a lipid-free diet, the fish of (30 to 35 gr) were fed for 8 weeks by experimental diets in 300 L tanks (n=36). The fish were fed two times a day at 10:00 am and 17 pm with 4 proteinlevels (45%, 50%, 55% and 60%) that was repeated 3 times in 60 days. At the end of the experiment, the blood samples were taken by heparinized syringes. Then RBC and WBC were counted. Hematocrit, Hemoglobin and blood indices showed no significant difference in different groups. The results of hematological parameters showed that the used diet was in optimal condition for culturing Sparidentexhasta.

In recent years due to severe drought and reduced rainfall in the Khouzestan Province, water salinity in some inland fish culture sites reached up to 9 ppt. So this research was carried out over a period of 21 days in salinities (3, 6, 9, 12ppt) and fresh water (>1ppt) for control on growth performance and survival in FINGERLING silver carp (Hypophthalmichthys molitrix). For this reason silver carp) weight: 13.55±0.726 g and total length: 11.04±0.093 cm) were placed in 250 l- fibreglass tank) 10 silver carp / tank (at 24.16±1.35oC. These treatments were tasted in three replicates. Fishes were biometric once per week (7, 14 and 21 days) through out the experimental period for evaluation of growth. The result of this trial indicate that salinities up to and including 3ppt did not affect weight gain, specific growth rate, survival and length. Higher salinities (6 and 9 ppt) produced significant stress, and adverse effects on these factors. In 12ppt all fishes died prior to 7 days. Silver carp, a freshwater stenohaline fish, exhibited good growth without any signs of stress up to 3ppt salinity. Silver carp could be cultured successfully at salinity up to 3ppt but above this level, salinity-induced stress could adversely affect growth and survival.

This research was carried out over a period of 21 days in the September - October of 2009 in Shahid Maleki Warm Water Fish Culture Centre in Ahwaz.FINGERLINGs of silver carp, (Hypophthalmichthys molitrix) (13.55±0.726 g, 11.04±0.093 cm) were reared at salinities of 3, 6, 9, 12‰ and 1>(as control) at 24.16±1.35 °C. Fishes were placed in 250 l-tank (10 silver carp /tank). These treatments were tasted in three replicates. At the end of experimental period, blood was collected from the heart for determination of haemoglobin and haematocrit. Salinity up to 3‰ did not affect these factors (p>0.05). Higher salinities (6 and 9‰) adverse effects on haematocrit, haemoglobin body moisture and survival (p<0.05). At 12‰ all fishes died prior to 7 days.Silver carp, a freshwater stenohaline fish exhibited no signs of stress in up to 3‰ salinity. These results demonstrated that changes in haemoglobin and haematocrit can be used as indices in response salinity sress on silver carp.

Despite the many advantage of oral vaccines, this kind of vaccines have a low efficiency and little application in aquaculture due to their antigens destruction in digestive system of fish. Chitin is a natural polymer, while Aeromonas bacteria produce a biofilm of it that cause to bacteria resist to gastric acid and intestinal enzyme systems. At first vaccine of Aeromonas hydrophilia biofilmproduced and then its oral and injection administration was evaluated in common carp. Therefore, 700 carp (46 ± 14) grams, 9 equal treatments and three replications as the first to fourth treatment with Biofilm Vaccine, inactivation Bacteria, Chitin + Culture media and Chitin were oral administered safely, the fifth to eighth treatments were immunized with the injection method safely, the ninth treatment without any vaccine was considered as control group. The fish were injected with concentration of LD50 of Aeromonas hydrophilia bacteria (Mc Farland 8= 2. 4×109) on the 60th day. The mortality rate was recorded within 10 days and the relative percent survival (RPS) of each treatment was determined. The results showed that the RPS levels highest were related to injection biofilms, oral biofilm and inactivation Bacteria injection, which was significantly higher than of the other treatments (P <0. 05). The efficacy of the injection vaccine was not affected by Biofilm (P = 0. 098), although the oral vaccine was influenced significantly by Biofilm (P <0. 05).

This study was carried out to determine the olfactory preference of the Persian sturgeon, Acipenser persicus, of 7-9g to 20 free amino acids, using one positive control and one negative control, totaling 22 treatments. The trials were done in 10 replicates.In the qualitative evaluation of juvenile responses, alanine and to a lesser extent glycine stimulated the strong and obvious feeding (searching) reaction that was also conformed by quantitative evaluation.The amino acids of leucine, histidine, cysteine, also isoleucine and proline promoted a low positive response. The quantitative evaluation verified the result, except for proline. Aspartic acid, tyrosine, glutamic acid and threonine stimulated negative responses as repelling agents. The result of quantitative assay showed the highest negative effect in the case of glutamic acid (p<0.01). Alanine and glycine could be, therefore, considered as appellants and glutamic acid as a repellent for the Persian sturgeon.

The lethal concentration of the Sefidroud suspended sediment in a 4-days experiment (LC50 96h) on stellate sturgeon FINGERLING (Acipenser stellatus) of 3-5g weight was investigated in 2005. Totally five concentrations and one control all in triplicate were considered. The results showed that LC50 96h and LC50 24h of sediments on stellate sturgeon were 8538.86 mg/l and 74267.70 mg/l, respectively.

In order to study the growth rate of stellate sturgeon, three earthen ponds with 2 hectares area were selected randomly. Two ponds were treated with 16 tons organic fertilizer and 40 kg Daphnia. The total culture period was considered 35 days. The physical and chemical parameters of water and also the density of zooplanktons and benthos were measured during the rearing period. Apart from these factors the gastrosomatic index (GSI), daily growth rate and the condition factor of the FINGERLINGs were also determined in order to assess the output of each pond. On the basis of the statistical analysis conducted, no significant difference was observed in the physical factors of the water in the three ponds but for nitrite values were significant.The major productivity of zooplanktons and benthic organisms were Daphnia (D. magna and D.pulex), cyclops and nauplii of cyclops.