Corrosion cast study is one of the procedures for studying the structure of the blood vessels in a particular tissue or organ. In the present study, the circulatory system of Silver Carp was studied by using four different methods of resin injection. 12 fish with a weight range of 850 -1000 g were obtained from a commercial fish farm. The Fish were anesthetized using a solution of 5% benzocain in 96% ethanol and injected intraperitoneally with heparin (4000 IU/kg). After 40 min, the fish were killed using an overdose of the benzocain solution, and then, fluid artificial resin made on the basis of methylmetacrylate was injected through the caudal artery, bulbus arteriosus, and dorsal and ventral aortas. The Fish were submerged for 24-48 hours in a bath water at room temperature until the polymerization and hardening of methylmetacrylate. Then, they were placed in a 25% KOH solution for 24-48 hours to obtain a maceration of the organic tissue. In this study, various parts of the heart and its vessels, gill vessels, gastric vein, portal vein, hepatic vein, dorsal aorta and its branches, renal and caudal arteries and related smaller vessels were also determined. Overall, it seems that the injection of resin via bulbus arteriosus of the heart was the best and most effective method for the corrosion cast study of the circulatory system in Silver Carp.

In this study, we have conducted an investigation on the brood stocks of 17 Gattan, presumably a rare native economic fish, at the Institute of Aquaculture in South of Iran and the Native fishery reproduction center of Dashte Azadegan. The measurements of live samples were as follows:  average weight, 25/1±559/3g. the average length, 45/9±4/001cm the average fork length, 49/1±4/2cm the average of total length, 53/5±4/9cm. Also, the average duration of sperm motility was reported as 309/2±64/5 seconds, mean sperm density was 47/5±16/3, the PH average of semen 7/6±0/9, and the average percent of sperm atrocity 45/2±15/8%. In addition, the average glucose, cholesterol, and the total protein semen in sequence are as follows 23/3±1/0, 51/76±28/8, and 1/1±0/9mg/DL. Furthermore, the averages of sodium, potassium, magnesium, calcium and phosphorus levels of semen were reported as follows: 432/4±79/22, 108/8±20/26, 2/7±0/6, 0/7±0/2, and 15/8±3/1mm/l. Additionally, the sperm head length was 1/3±0/3 micron, the average length of agella 2/3±0/7micron, and the average total length of the sperms was 3/7±1/0. Overall, the results from this study have provided necessary information to illustrate that Gattan sperm cryopreservation is successful at the time of sperm motility and sperm concentration

In this study, the effect of eugenol concentrations and induction time on the blood cortisol and glucose of gold fish (C. auratus) was investigated. The Experiment was conducted in two parts: first, the goldfish were exposed to 50-150 ppm eugenol over 40-360 s and blood samples were collected. In the second experiment, fish were exposed to 50-175 ppm eugenol and were allowed to reach stages 4 and 5 of anesthesia. Blood samples were collected and used to determine the levels of cortisol and glucose. The Correlation between cortisol or glucose with induction time or eugenol concentration was also investigated. At 50 and 75 ppm eugenol, cortisol and glucose levels were significantly affected by induction time. In 100 and 125 ppm eugenol, cortisol and glucose levels were significantly affected by induction time, eugenol concentration and interaction. In 150 ppm, cortisol levels elevated in line with the induction time. However, there was no significant change in glucose levels. Correlations between cortisol as well as glucose with induction time and eugenol concentration suggested that induction time is the key factor determining cortisol and glucose levels. Induction time is more important than eugenol concentration for blood cortisol and glucose determination in goldfish. Accordingly, goldfish should be anesthetized with high concentrations of eugenol over a short period of time to minimize the stress response

Spirlin,Alburnoideseichwaldii, is an abundant riverine fish in the southern Caspian Sea basin. The aim of this study was to investigate the morphological structure of Alburnoideseichwaldii populations in Karganrud and Chalus rivers based on morphometric characters, using truss network system. Sixty specimens of Spirlin from the rivers (30 specimens were caught in August 2010 from each river) were studied and compared. Fourteen landmarks were selected and 91 distances were measured between the landmarks on the left side of each specimen. Principal Components Analysis (PCA) and Discriminate Function Analysis (DFA) were applied to identify influential truss variables to differentiate between populations and sexes. The results showed that the morphometric characters were not useful for separating the sexes Discriminate Function Analysis separated these two populations. These variables seem to be under the influence of environmental factors such as water flow, the slope of the rivers, water physicochemical conditions and feed conditions of the fish populations

Knowledge on the characteristics of exotic species is important in ecological studies and has applications in ecosystem and species management. This investigation was conducted to study some of the growth characteristics of Gambusia holbrooki in six water-bodies in the north-east region of Iran, (Golestan province). A total of 8500 specimens was collected monthly using plankton-collector net(sachuk) from February to September 2012. Age was determined using the opercula and scales. The results showed that the maximum age was 2+ for both sexes. The largest specimen had 59 mm TL and 3.83 g weight. The largest average total length and weight were 34.1 ±0.68 mm (±SD) and 0.71 ± 0.47 g (±SD) in Gomishan wetland for females, and the smallest average total length 24.7 ±0.24 mm (±SD) for males in Alakuli reservoir, the smallest average total weight 0.20 ± 0.06 g (±SD) in Alma-Gol wetland and 0.20 ± 0.29 g (±SD) in Ala-kuli for males. Weight-length relationships were significant. Growth pattern was negative allometrice for males and positive allometrice for females, except for the females of Ala-kuli reservoir. The smallest condition factor was observed in Bandar-Torkaman for males and in Gomishan wetland for females

In this study, 236 Barbus lacerta specimens were collected (monthly) from three stations in Sefidroud river during eight months in order to survey some biological characteristics (December and March, 2011 and April to September 2012). The specimens ranged in size from 48 to 227 mm, total length and weighed from 1.03 to 113 g, total weight. The Average length of males and females was 108.39 ± 19.56 and 135.88 ± 32.31 mm, respectively, and mean weight 11.35 ± 6.13 and 25.33 ± 15.16 g. The Results of age determination by means of the gill cover bones (opercula) suggested that the maximum age found in females was 4+ and in males 3+. Also, the most abundant age groups were 2+ and 3+ for males and females, respectively. According to the results, the overall sex ratio of males to females was 1: 1.13 and there is no significant difference from the expected ratio of 1: 1 (P> 0.05). Length-weight relationships were estimated as W = 0.0054TL3.1628 for males, and W = 0.0036TL3.3244 for females implying that growth was positively allometric for both sexes. The von Bertalanffy growth function was estimated to be for males and for females. The greatest spontaneous growth observed in both sexes was between the ages of one and two and with an increase in age, this rate showed a significant decrease. In addition, gonadosomatic index showed that the reproduction period of this species in Sefidroud River occurred around April-June, with the peak of 7.03 ± 1.58 and 6.36 ± 2.40 in May for males and females, respectively.

The aim of this study was to investigate the age, growth and reproduction of C. c. gracilis in Shirud River estuary from June 2011 to July 2012. A total of 157 specimens of C. c. gracilis were collected using a throw seine, 8mm mesh. Age determination was done by means of scales. The length range was measured as 85.5-232 mm. Sex ratio was 1:2.74 which was significant (P<0.05). The age range was 0-2 years for males and 0-4 years for females. Also, the age of 2 was group dominant. The Von-Bertalanffy equation coefficients were L&infin=31.3 mm, K=0.2/year, t0=-0.4 years. Length-weight relationship was isometric. The total absolute fertility was determined 3562.56±1546.81 and had significance and correlation with the total length, and body weight. The range of egg diameter is 0.3-2.3mm. The gonad development peak was determined in March and April. The Growth parameters of C. c. gracilis are similar to the specimens of other streams Gorganrood basin

We studied the spawning sites of the endemic endangered fish Aphanius vladykovi in the littoral zone of the only remaining lake habitat, Choghakhor lagoon. During this study, we inferred by the direct observations of the spawning and the location of spawned eggs, the reproduction behaviors of the broods which was used to determine their preferred spawning nests. It revealed that the nest abundances of the species clearly related to the spawning substrates, such as gravel bottom and the special aquatic vegetation as well as the depth and the distance from the shore. Due to the water level depletion, the initial habitat of the fish (depth 55±1.1 and 555±18.8 cm from the shore) has been modified and degraded and often there is an apparent lack of suitable spawning substrates (lower depth 40±1.2 and less distance 190±12.2 cm from the shore). Growth models for both sexes were stated by the von Bertalanffy function as Lt=4.25(1-e-0.37(t-0.89)) for females and Lt=4.12(1-e-0.37(t-0.83)) for males. The weight-length relationship was described as W=0.026 L3.01 (r2=0.97) for males and W=0.026 L3.03 (r2=0.98) for females. The slope of the regression line (b) fitted through the weight-length data suggesting a positive allometric growth model for both the females and the males. It is concluded that the habitat specialization of the limited zone of spawning is an important element in the survival of the endangered fish as a critical stage in the habitat requirements of its population

In order to evaluate the diet composition of bartail flathead, sampling was conducted from December 2009 to November 2011. In this study, a total number of 470 fish were measured, out of which 446 pieces were examined. The length-weight ratios were calculated as W=0.000005FL3.07 (n=198, R2= 0.82) for females, W=0.000009FL2.95 (n=248, R2=0.82) for males and W=0.000004FL3.10 (n=470, R2 =0.86) for total fishes. The analysis of FP and IRI results showed that fish (75%) is the main food source for bartail flathead, followed by shrimp (25%) as a secondary food source and crabs and cuttlefish (5%) as accidental food sources. Overall, the analysis of the stomach contents for bartail flathead indicated that this species is a moderate feeder.

The sand goby Neogobius pallasi (Berg, 1916) belongs to the family Gobiidae which has a wide distribution in the south of the Caspian Sea basin and its tributaries. The purpose of this study was to determine some of the morphological parameters of sand goby and the appropriate characteristics for the separation of populations in Kaboodval, Zaringol and Shirabad Streams. Both males and females consisted of five age groups (0⁺-4⁺). Seven meristic and 31 distance-based morphometric characters from 104, 30 and 62 specimens were investigated in three streams during the summer in 2008. The comparison of the morphological characteristics among the samples of sand goby showed the significant differences in three Streams (p<0.05), but principal components analysis (PCA) showed that the low characteristics play a role in the population separation. Only the mouth width, lower jaw and upper jaw coefficients were greater than 0.75. It seems that there is more overlap between the samples of Kaboodwal and Zaringol compared to those of Shirabad. This finding is also consistent with their geographic distances

This study surveyed Intrabasin variation in the growth models of C. capoeta in 5 streams of Gorganroud River basin during the reproduction season between April and May, 2010 and 2011. A total number of 1500 specimens were caught through electro-shocking. Total length, total weight, sex and b-value were determined. Total length ranged between 4.1 and 20 cm and total weight ranged between 0.81 and 108.34 g in Pishkamer and Tilabad streams, respectively. The growth models were estimated separately for each sex. The b-value ranged from 2.90 for the males of Pishkamer and Tilabad to 3.13 for the females of Chelchai. Growth model was positive allometric (b>3) for most of the females, while the males had different growth models. A comparison between the b-value of the streams can aid the identification of the factors contributing to the growth model of the populations. In fact, different types of habitats differ in their general environmental conditions which can cause reactions. This reflects a change in the body form with population. This variation in the allometry coefficient of C. capoeta suggests different growth strategies for the populations.

The manipulation of river ecosystems through dam construction or other changes transforms their natural state into a reservoir and causes aquatic animals to face new ecological and evolutionary challenges. This study was conducted to survey the impacts of Tarik dam on the body shape of two isolated populations of riffle minnows using the geometric morphometric method. Thirty specimens were captured from each side of Tarik dam. The left side of each specimen was photographed using a digital camera, and eighteen landmark points were digitized on two-dimensional images using TpsDig2. After GPA, landmark data were analyzed using DFA and TtestHotelling and the patterns of body shape differences between two populations were illustrated on a wireframegraph. The Results revealed significant differences between the body shape of the two studied populations (P<0.0001).Body shape differences between the two populations were related to head, snout, anal fin and caudal peduncle regions. These findings suggest that the characteristics of a new reservoir along with geographical separation act as evolutionary factors bringing about change to the morphological attributes of the fish inhabiting these areas

The phenotype of an organism not only reflects its genome, but also it can display its habitat and life style features. Hence, this study was aimed to apply the landmark-based geometric morphometric method in the study of the phenotypic plasticity of killifish (A. sophiae) from Cheshme-Ali Damghan and Shour river of Eshtehard. A total of 86 specimens were sampled from Cheshme-Ali (52 specimens) and Shour river (34 specimens). The left side of each specimen was photographed using a digital camera and fifteen landmark points were digitized on 2D images using TpsDig2. The landmark data of the two sexes of both populations were analyzed separately using DFA and T-test Hotelling after GPA superimposition. The patterns of body shape differences between the two sexes of both populations were illustrated. The results revealed significant differences between the body shape of two sexes in both populations (P<0.001). The morphological difference patterns between the two sexes were found in the depth of the body and caudal peduncle and the position of the pectoral fin. The findings of this study suggest that different characteristics of the habitats have driven changes in the morphological attributes of the inhabitant killifish populations along with geographical separation as evolutionary factors.

This study was carried out from May 2011 to June 2012 in order to identify the fish species and their abundance in Hoor-Al azim wetland. Sampling was done using Gill nets on a monthly basis. According to the results 15 species from 3 families were identified. Carasobarbus luteus at 28.7% and Mesopotamichthys sharpeyi at 24.6% had the highest frequency.The highest number of species were observed in autumn with 11 species at Rofaye station and the lowest number of species were in summer with 7 species at shat Ali station.

O. argyrogramma is the only species of the genus Oxynoemacheilus. It is distributed in the freshwaters of Iran and Iraq. The present paper reports a study carried out to investigate the genetic diversity and population structure of O. argyrogramma in Sepidbarg and Gamasiab river basins in Iran. 100 samples (50 samples from each river) were used in this survey. Microsatellite markers were increasingly used in population genetics studies. In this study, a total number of three microsatellite loci and two populations were studied. The average number of allele levels in the population was 13, which was more than the reported values for freshwater fishes. The expected and observed heterozygosity means were 0.652 and 0.876, respectively. Approximately all of the loci showed a deviation from the Hardy-Weinberg equilibrium. The genetic similarity and distance between the two populations were 0.346 and 0.707, respectively. According to the analysis, it seems that O. argyrogramma has a desirable genetic diversity in the investigated regions.

A 28-day feeding trial was conducted on the A. guldenstaedtii larvae during the early stages of active feeding, using three live foods, namely Daphnia magna, Artemia urmiana and a mixture of both (Daphnia 50% w/w and Artemia50% w/w) with a feeding frequency of 6 times per day. The healthy larvae of A. guldenstaedtii were provided from the sturgeon center of Marjanii. Having three replicates (100 fish per tank), the fish larvae in three treatments (A, D and D+A) were scheduled and fed based on 30 percent of the body weight in a day by Artemia urmiana nauplii, Daphnia sp. And a mixture of both, respectively. The initial mean body weight of fish larvae was 35.332.50 mg and its density was 2 individuals per liter. This experiment was conducted in a completely randomized design. The fish were weighed individually at the beginning and end of the experiment. The proximate composition of the fish samples (the beginning and end of the experiment), Artemia nauplii, Daphnia and a mixture of them were determined. Maximum protein retention efficiency (72.29%), lipid retention efficiency (14.61%) and energy retention efficiency (44.81%) were obtained in treatments D+A (fish larvae fed with a mixture of Artemia nauplii and Daphnia), while the minimum of protein efficiency ratio (6.18) and energy efficiency ratio were showed in treatments of D and A, respectively. The results of the present observations demonstrated that the exploitation ability of A. guldenstaedtii larvae in using live food was different.

The effects of fishing mortality on the spawning potential of a stock. In presentresearch, spawning stock biomass of Otolithes ruber was carried out using Virtual Population Analysis (VPA) data (based on previous study) in the coastal waters of North-West Persian Gulf. Spawning stock biomass ranged from 4110 to 11756 tonnes, and fishing mortality ranged from 0.28 to 0.96 per year. Spawning stock biomass per recruit ranged from 22.8 to 44.7%, and avererage spawning potential ratio estimated between 26 to 31%. Fisheries mortality showed a strong and negative correlation with spawning stock biomass per recruit. Percentage spawning potential and SSB/R showed that they are lower in the some years in the range of biological reference points. However, this assessment finds that the stock is near full exploited. But according to reference point’s results, sustainable stocks need actual planning by fishery managers.

A 12-week feeding experiment was conducted to evaluate the effect of dietary betaine as a feed attractant on growth, survival and resistance to some environmental stressors on wild Common carp (Cyprinus carpio Linnaeus, 1758) juvenile. Fish by the weight of 2.51±0.07 g and density of 20 fish per aquarum. Put through Six treatments of different levels of betafin including 0 (control), 0.5%,1%, 1.5%, 2% and 2.5% added to diet containing 35% protein and 3% lipid. At the end of experiment, final growth and feeding indices including final weight ,food conversion ratio ,specific growth rate ,survival rate and resistance to environmental stressors including thermal (35°c) and salinity (35 g/lit) stress assessed. According to the results of this study, a general enhanced growth performance and feed efficiency were observed in fish fed on the diet containing 2.5% betain (P<0.05). There were no significant differences in survival rate among all treatment groups (P>0.05). The highest of survival time after salinity and thermal challenge were observed in 2.5% betain (P<0.05). The results showed that the addition of betain at the level of 2.5% to the diet of wild common carp improves growth performance, feeding efficiency and resistance to environmental stress.

Study of longline&#39;s was carried out to identify the catch composition on the Persian Gulf water. The study areas were from Arvand-Rod to Musa- Khor. Sampling was carried out in three season’s spring, summer and autumn (9 mounths) on a cruise through out month.Twelve specie were caught and indentified. catch composition consisted of Acanthopagrus latus (Houttuyn, 1782), Acanthopugrus bifasciatus (Forsskål, 1775), Lethrinus nebulosus (Forsskål, 1775), Rachycentron canadum (Linnaeus, 1766), Epinephelus coioides (Hamilton, 1822), Pomadasys kaakan (Cuvier, 1830), Diagramma pictum (Thunberg 1792), Acanthopagrus cuvieri (Day 1875), Arius thalassinus (Rüppell, 1837), Carcharhinus sorrah (Müller & Henle, 1839), Rhynchobatusdjiddensis (Forsskål, 1775), Pastinachussephen (Forsskål, 1775). The grouper (Epinephelus coioides) and cobia (Rachycentron Canadum) were respectively accounted for the highest (24.19) and smallest (1.47) percentage of the fishing. Thisstudy reveals that thesize of fish and the depth have a positive relation ship.

Effect of garlic powder was surveyed on growth and hematological parameters of Huso huso in 2013 at Shahid Marjani Sturgeon Fish Propagation and Rearing Center, Gorgan. Experimental diets were provided with add of different levels of crude garlic powder (0, 1.5, 2 and 3%) in formulate diet. Fish with the average weight of 136.08 ± 0.7 g and average length of 33.43±0.2 cm were fed 3% of body weight daily for 4 weeks. At the end of experiment, biometry and blood sample collection carried out to assay hematological factors. Statistical analysis showed that body weight gain, specific growth rate and daily growth rate increased significantly in fish fed with diet containing 1.5% garlic compared to control group, also condition factor increased significantly in all fish fed with diets containing garlic in comparison with control group (P<0.05). Feed conversion ratio decreased significantly in fish fed with 1.5 % garlic compared to control group (P<0.05). Hematological factors (leukocytes count, hemoglobin, mean corpuscular hemoglobin and erythrocytes count) showed significant difference in all treatments in comparison with control group (P<0.05). The best response observed in fishes fed with diets containing 2% and 1.5% garlic.