ALBERT

Description: In order to introduce a new sturgeon hybrid to aquaculture industry, the possibility of hybrid production by crossing between Siberian and Persian sturgeons and its comparison with its pure parents using morphometric, molecular, cytogenetic and growth performance were conducted. For this purposes eggs and sperms of two pairs of Persian and Siberian sturgeon were collected and reciprocal crosses with 4 treatments were conducted. In treatment 1, Persian sturgeon as control (male and female of Persian sturgeon), treatment 2 (as type I hybrid) from crosses of male Persian sturgeon with eggs of female Siberian sturgeon in treatment 3 (type II hybrid) using crosses between male Siberian sturgeon and female Persian sturgeon and finally treatment 4 by crossing male and female of Siberian sturgeon were used. For each treatment 200 gr. of eggs were fertilized with one ml. of sperm and morphological, meristic parameters of parents and offspring were recorded. For growth comparison of fingerlings of control and hybrids in 3 different phases were measured. In phase (I), larvae rearing from 46 mg. up to 6600 mg. were conducted for a period of 10 weeks. Samples were collected once every two weeks and biological parameters were recorded. In rearing phase II for a period of 330 days, growth comparison were conducted for fish from 6.5 gr. to 750gr. and biological parameter were recorded once every month, where daily growth rate (gr./day), FCR, Specific growth coefficient (percentage per day), increase of body weight, food efficiency and protein efficiency ration were analyzed. In rearing phase (III), from 600 gr. to 2000 gr. for a period of 43 weeks, similar to phase (II) all biological parameters were analyzed, where 26 morphometric and meristic parameters of pure and hybrid parents and offspring were compared both for individual and ratio status of parameters. For genetic analysis and variation between control and hybrid specimens the microsatellite analysis were conducted. For this purposes, genomic DNA were extracted from fin tissues of brood stocks and fingerlings and 10 pairs of specific primers (Afug 56, Afug 63, Afug 241, Afug 229, OX 27, Afug 686, Afug 195, Afug 12, IS 68 and Afug 160) were used. Then PCR Products were electrophoresed on 6% polyacrylamide gel and then were stained with Nitrate silver and alleles were evaluated based on its length (base pair). Cytogenetic analysis and number of chromosome of control fish and hybrid were compared using white blood cell culture method and chromosome spread of parents as well as offspring were prepared by Gimsa staining and were visualized under light microscope. For sexual gonad development, laparoscopic method with light camera (Model M-CAM 1700) were used to differentiate 34 pieces of control and hybrid fish and gonad status of ovary and testis were analyzed. In present investigation the results indicate that, in phase (I) of larvae culture, a significant differences were observed after 10 weeks of feeding (p≤ 0.05) in hybrid and control groups. Maximum growth rate were observed in Siberian sturgeon larvae, followed by type I hybrid, type II hybrid and Persian sturgeon larvae. In phase (II) , growth rate of Persian sturgeon were lower than Siberian sturgeon. For period of 330 days of rearing periods, the control Siberian sturgeon had 1.4gr. weight increment per day, while Persian sturgeon had only1. gr./day. However the hybrid type (I) had an average daily growth of 1.5gr/day and lower growth performance were observed in type II hybrid with daily growth of 1.5 gr./day. In phase (III), growth rates were varied at different age group. The daily growth rate of Siberian sturgeon was 4.5gr/day, while is control Persian sturgeon was 2.6 gr/day. The Siberian sturgeon within 47 weeks of rearing grown from 655 gr. to 2016 gr., however Persian sturgeon for the same period reached from Siberian sturgeon with male’s Persian sturgeon had higher type II hybrid showed opposite results for the same growing period and reached from 640 gr. to 1680 gr. In conclusion of growth performance can be stated that the hybrid from crosses between female Siberian sturgeon with male Persian sturgeon presented highest growth rate in comparison to control hybrid. This excellent achievement can be considered as a big step toward sturgeon aquaculture for meat and Caviar production. In analysis of morphometric characters 26 parameters were investigated which in 18 parameters showed significant differences (p≤ 0.05) which indicate clear distinguish able of hybrid performance in compare with parents where Siberian sturgeon has longer snout compare to Persian sturgeon and its size are intermediate in hybrids. In relative ratio of characters, out of 9 characters totally 7 characters showed significant differences (p≤ 0.05). In molecular analysis using microsatellite primers totally 400 DNA samples of hybrid as well as the control fish were investigated. Totally 784 allele were detected in which 363 alleles were belong to control fish and 421 alleles in hybrid. In this study, 19 alleles with different sizes were observed in hybrids rang from (120bp) in Aox27 primers (400bp) in AFUG229 primers. In comparing of all primers, the primer AFUG160 and AFUG195 with 2 alleles and primer AFUG686 with 7 alleles showed the minimum and maximum allele numbers.The banding patterns were monomorphic in 66 loci of control fish and 65 loci of hybrids, and in 77 loci of control fish and 73 loci of hybrids were diploid in 9 loci of control fish and 12 loci of hybrid fish were tetraploid, in one locus of control samples and 3 hybrid samples were pentaploid and finally within 10 pairs of primers 7 sets were disomic, 3 primers (Afug241, Afug686, Aox27) were tetraploid and 6 primers of (Afug63, Aox27, Afug688, Afug12, Is68, Afug160) showed excellent allele heritability which indicate the high efficiency of microsatellite techniques. In evaluation of the status of gonad development as well as determination of sexual stages laprascopic method indicated that out of 9 samples of Persian sturgeon (4 females and 5 male) were in stage of 2 & 3 gonad development. Out of 8 Siberian sturgeon (4 males+4 females) stage 2, 3, 4 were detected. In 7 gonad samples of hybrid (Female Persian and Male Siberian) totally 5 male and 2 female were observed at stage 3 and 4 gonad development. In analysis of 10 samples of type II hybrid (female Siberian × male Persian) 3 female, 6 males and 1 deformetic were observed. Cytological studies on 30 metaphase palate from 6 fish samples showed that the number of chromosome in hybrid are as same as parents 2n=250±10 where all control and hybrids similar to its parents showed 240 chromosome. In conclusion, It can stated that, this study successfully introduced a new sturgeon hybrid for sturgeon farming both for meat and caviar production. Considering the common name of sturgeon parents used for production this hybrid, we call this hybrid as (Siper) where Si instant for Siberian sturgeon and Per comes from Persian sturgeon.

Description: Iranian Fisheries Science Research Institute

Description: Published

Description: The optimum dose of ultraviolet (UV) irradiation to produce gynogenetic Caspian salmon, Salmo trutta caspius, with emphasis on the "Hertwig effect" and photoreactivation (PR) were investigated. The sperm of Caspian salmon was irradiated with UV at 2010 ± 200 µw.cm-2 in different times including 0, 1, 3, 5, 8, 10, 15, 20, 25, 35 and 45 min and was allowed to fertilize normal ova; the fertilization, eyed and hatching rates were calculated to assess the performance. Using the irradiated sperm decreased the fertilization, eyed as well as hatching rates and the so-called "Hertwig effect" was observed, with the time-dependent decrease in the hatching rates at 0+ to 3 min irradiation, but better hatching rates were observed at more prolonged irradiation times. The best hatching rate was achieved at 25 min of UV irradiation; after that the survival rates rapidly declined to near zero. For PR studies, the semen was irradiated with UV (5, 30 and 120s) and untreated semen (0s) was used as control. Irradiated semen and/or fertilized eggs by treated semen were exposed to visible light (60 W) at a distance of 30 cm for 10 min; the eyed and hatching rates were measured. UV irradiation as low dose as 5s, significantly decreased the hatching rate (P 〈0.05). Semen and/or eggs illumination with visible light could not improve the survival rates (P 〉0.05). So, based on the results of this study, it was impossible to detect any PR mechanism in Caspian salmon.

Description: To improve Persian sturgeon nutrition and determine its nutritional requirements, a growth trial was conducted to measure optimum dietary protein to energy ratio in Persian sturgeon sub-yearlings. Four diets: H (P/E=21.33mg/kJ), N (P/E=20.24mg/kJ), L (P/E=19.22 mg/kJ) and M (P/E=18.26mg/kJ) were used in the experiment. Triplicate groups of fish were kept in 500L fiberglass tanks under homogenous culture conditions (dissolved oxygen, light and water flow rate) and fed with the experimental diets. Fish were fed to satiation four times per day during 130 one fourth ¬ days of experiment when the average water temperature and dissolved oxygen were 12.82 plus or minus 1.48 degree C and 9.55 plus or minus 0.18 mg/l respectively. Fish in all treatments grew fast and efficiently utilized the diets. Growth rate, FE, GR, SGR and PER increased with decreasing dietary protein to energy ratios. A higher growth was observed in the fishes fed with lower P/E ratios. Food intake and fatness coefficient increased with increasing dietary energy and decreasing P/E ratios. There were no significant differences in feeding efficiency (FE) and protein efficiency ratio (PER) in fish fed with diet N (high carbohydrate and low lipid content) and diet L (low carbohydrate and high lipid content). We conclude that the Persian sturgeon is able to use lipids and carbohydrates as non-protein sources of energy. The results of the present study demonstrated that the protein content and P/E ratio for optimum growth and efficient protein utilization in Persian sturgeon is 40% and 18.3-19.2 mg protein/kJ energy, respectively.

Description: Six diets supplemented with 0, 100, 200, 400, 800, and 1600mg/kg L-Ascorbyl-2-Polyphosphate (APP) as vitamin C, were fed to juvenile beluga sturgeon in three replicates for 16 weeks. Fifty five fish with an average weight 38.1 plus or minus 0.5 g were distributed to each tank after adaptation to the experimental diets. Most of the growth performance indices at week 4 indicated significant differences (P〈0.05), except in CF and PER (P〈0.05). The survival was affected by dietary treatment at week 4 (P〈0.05). No deficiency sign was observed during the trial. Results of this study indicated that vitamin C can have remarkable effects on growth indices in different growth periods. Therefore, regarding the effects of vitamin C on the growth indices and in the fish weight range used in this study, 100-200 mg/kg vitamin C (APP) can be considered as the optimum level for rearing the fish.

Description: This study was conducted to codify the guideline and indexes of broodstock management in salmonid fish and cryopreservation, selective breeding and sex reversal in hatchery to attain responsible aquaculture development. Cryopreservation includes of sperm and egg in term of economic is important in aquaculture. In this report mentioned the type and name of material. All female and sex reversal fish are produced by steroid hormone which mentioned in this report. Selective breeding include individual selection and family selection which could be used for genetic improvement of fish.

Description: A feeding trial was conducted to examine the effects of dietary supplementation of lysine and methionine on growth, nutrient utilization and carcass compositions in beluga, Huso huso. Four experimental soy protein based diets D0 (without lysine or methionine supplementation), D1 (lysine supplementation alone), D2 (methionine supplementation alone) and D3 (both lysine and methionine supplementation) were fed to triplicate groups. 240 fish with an average weight of 144.6 ± 4.64 g were fed the experimental diets for 12wk. L-Lysine and DL-methionine were added to the diets containing 344 g kg-1 soybean meals at 22.02 and 12.94 g kg-1 of dry diet respectively. Significant higher weight gain, specific growth rate, protein efficiency ratio, condition factor, feed efficiency ratio, whole muscle protein and protein apparent digestibility were observed in fish fed soya protein-based diet supplemented with both lysine and methionine than that of fish of other dietary groups. There were no significant differences among fish fed diet supplemented with either methionine or lysine. Growth performances, feed utilization, carcass composition and apparent digestibility coefficients of protein, lipid and dry matter of fish fed control diet was significantly lower than those of fish fed diet supplemented both lysine and methionine and supplemented with either methionine or lysine. It can be concluded that beluga, fingerlings effectively utilize the supplemental amino acids (L-Lysine at 22.02 g kg-1 dry diet and DL-methionine at 12.94 g kg-1 dry diet) in the diets containing 344 g kg-1 soybean meals for better carcass proximate compositions, growth performance and feed efficiency and utilization.

Description: The study on the ecophysiological impacts of stress in female Persian sturgeon broodfishes revealed that the average cortisol level varried in all broodfish caught at the Sefidrud River (163.38±21.2ng mL-1), Sefidrud River estuary (260.27±19.7ng mL-1) and Gorganrud River estuary (179.38±20.8ng mL-1). The variations in serum glucose levels were 140.65±12.05mg dL-1, 144.44±5.9mg dL-1 and 126.24±11mg dL-1, respectively. The maximum level of cortisol (781 ng mL-1) and serum glucose (281 mg dL-1) were observed during the transport of broodfish from the capture stations to the hatcheries and the minimum level of cortisol (25.2 ng mL-1) and serum glucose (33 mg dL-1) were observed during the confinement of broodfishes in the breeding ponds. The rhythmic and significant variations of cortisol level during capture, handling, transport and confinement of female Persian sturgeon broodfish in all three regions can be regarded as a valuable indicator of stress

Description: The effects of stocking density of eggs and larvae were studied related to the morphological deformities appearance, percentage of survival, and growth rate, in order to achieve the most suitable stocking density for eggs and larvae in incubators and rearing tanks. The egg stocking densities were 500, 700 and 900 g per incubator for great sturgeon, 500 and 1000g per incubator for Persian sturgeon and 400 and 425g per incubator for stellate sturgeon. Larvae were stocked at densities of 10000, 15000 and 20000 larvae per m3 for great sturgeon, 21660, 41004 and 69000 larvae per m3 for Persian sturgeon and 15770, 23250, 57660 and 62250 larvae per m3for stellate sturgeon. The results indicate significant differences in percentage of survived in fertilized eggs (p〈0.05). By transferring the larvae into the fibreglass tanks, growth and survival rate decreased, whereas mortality and incidence of deformities increased as stocking density increased particularly on the onset of exogenous feeding. In the present study totally 20 types of deformities including bent spine, hunched back, hanging or looped tail, fin deformation, stunted body length and etc. were registered. The results showed that the morphological deformities frequency in dead and live fish were higher in high stocking densities comparing to the low stocking densities.

Description: A two-phase random growth test was conducted to evaluate the effects of feeding rate on growth performance, food conversion ratio (FCR), specific growth rate (SGR), feeding efficiency and price index of reared Huso huso fingerlings in fiberglass tanks (2x2x0.53 cm). Rearing conditions such as diet, dissolved oxygen, light, water flow, fish density and feeding frequency were kept similar for the tanks. In the first phase, 180 fingerlings with a mean weight 867.86±17.42g were fed for 100 days in four treatments and three replications at feeding rates 1, 2, 3 and 4 percent of their biomass. In the second phase, also four treatments and three replications were applied to 84 Huso huso with a mean weight 2096.1±35.6g. In this phase, the fish were fed for 125 days with 0.75, I .5, 2.5 and 3 percent of their biomass. During rearing period, water temperature was 25.52±1.78 and 14.82±0.48 degrees centigrade and dissolved oxygen was 7.6±0.3 and 7.89±0.18 mg/lit, for the two phases respectively. The fishes were fed four times daily with a diet containing 40% protein, 13% fat and 9.9% ash. All treatments induced fast growth in the fish, but feeding ratios were different in their effects on the growth (P〈0.05). Weight gain percentage, specific growth rate (SGR), food conversion ratio (FCR), feeding efficiency and price index indicated that lower feeding ratios were more effective in causing fish growth (P〈0.05). So, increase in feeding ratio directly increased daily food consumption (D.F.C) and negatively affected the feeding efficiency, food conversion ratio, specific growth rate and price index (P〈0.05). The results showed that in phase one, when the fish were given food as much as two percent of their body weight, one unit of meat was produced by consuming 1.92 units of food. In the second phase, feeding fish with 0.75 percent of their body weight resulted in producing one unit of fish meat per 1.82 units of food consumed. Also, in the two phases, application of higher than 50% feeding ratio increased costs while no significant trend in fish growth was detected. It can be concluded that regarding the water temperature, the optimal feeding rate for fishes weighing 850 to 1900 grams and those weighing 2050 to 3300 grams are 2 % and 1 % of body weight, respectively.

Description: The lack of sustainable management programs has resulted in the drastic decline of sturgeons stocks in the Caspian Sea in the past two decades. Legal catch quotas for all Caspian littoral states has dropped from 28500 tons in 1985 to 460 tons in 2007 while caviar production in the Caspian Sea during the same period decreased from 3000 tons to 70 tons. Caviar production in the I.R. of Iran dropped from 305 tons in 1985 to about 11 tons in 2007. The "Strategic and applied research planning for sturgeon management and conservation" was developed with the collaboration of academicians from universities, researchers, experts, fishery authorities and representatives of the executive government to maintain sustainable development and rational management of sturgeon stocks in the Caspian Sea. The preparation and development of this planning was carried out through 121 sessions (2100 person hours) A comprehensive report (375 pg) was prepared which was divided into five volumes; Volume I comprises an introduction, objectives, strategies and planning, present status of production and caviar harvest, catch and export quotas, revenue generated and release of sturgeon fingerlings, Volume II comprises analysis of the problem by constructing a problem tree with 8 broad categories to analyze 344 problems and an objective tree which is the hierarchic flowchart of objectives with 9 broad categories with 241 items, Volume III comprises a review and analysis of previous and ongoing research (414 projects) on different aspects of sturgeon during the past 40 years, Volume IV comprises prioritizing research objectives outlined by the objective tree and finally Volume V which prioritizes primary objectives for 14 executive and 10 research programs. On the basis of the evaluation of the present status and for the sustainable development and rational management of sturgeon stocks a strategic and applied research planning program was proposed and developed within the framework of three primary objectives; 1) Management and sustainable use of Caspian Sea resources (5 programs), 2) Rehabilitation and restoration of stocks (5 programs), 3) Development of aquaculture (4 programs). The applied research program for each proposed executive program was outlined in 10 programs, 42 comprehensive plans and 222 projects. The primary objective on management and sustainable use of Caspian Sea resources includes 5 programs, 14 comprehensive plans and 63 projects, while the primary objective on rehabilitation and restoration of stocks includes 4 programs, 16 comprehensive plans and 87 projects. The primary objective to address sturgeon aquaculture includes 1 program, 12 comprehensive plans and 72 projects. The impacts and outcome of each of these programs was determined and presented. It is evident that if the present situation persists, the catch figures for adult sturgeon specimens and caviar production in Iran will reach zero in 2021. But if concerted efforts are taken and the proposed strategic and applied research planning program is executed (commencing from 2009) we can put a halt to these declining trends. By producing sturgeon fingerlings to restore population abundances, by conserving and protecting them in the Caspian Sea and by conducting applied research we can produce 206.4 tons of caviar by the year 2033. Apart from harvesting caviar from the Caspian Sea we can also annually produce 3000 tons sturgeon meat and 60 tons farmed caviar starting from the year 2023. The total budget proposed for implementation of this program for a period of 14 years (2008-2022) is USD 2483 million. If this budget is allocated in time and the proposed strategic program is properly and totally implemented, we can not only save many sturgeon populations from extinction but also ensure job opportunities for 6000 fisherman, provide 1480 new job opportunities and annually produce 266 tons of caviar which will generate USD 4957 million.