Sex steroid levels, reproductive indices and histological examination of gonads in adult male and female Caspian shemaya, Alburnus chalcoides

Reproductive status of Alburnus chalcoides adults from Anzali Wetland was investigated by histological examination of gonads, assessment of sex steroids (i.e. Progesterone (P), Estradiol-17ß (E2), Testosterone (T)) and reproductive indices (i.e. absolute fecundity, oocyte diameter, hepatosomatic index (%HSI) and gonadosomatic index (%GSI)). Totally, 42 females and 16 males were captured during March to May 2014 by gill net and divided into two age groups including 2 year olds and 3 year olds. In each age group, fish were classified into two groups depending on maturation stage i.e. matured and maturing fish. According to the results obtained, in each age group, there were no significant differences between matured and maturing males and females in terms of absolute fecundity (p>0.05). In each age group, oocyte diameter was higher in matured fish than in maturing individuals (p<0.05). In 2 year old males and In 3 year old females, higher HIS values were recorded in maturing fish compared to matured fish. In females, the plasma levels of E2, T as well as P were significantly higher and lower in maturing fish and matured individual, respectively. In males, only plasma T was higher in matured fish compared to maturing fish and other assayed steroids did not show significant differences. Also, the histological examination of gonads from 10 males and females showed that all fish were in the final maturation stages

Osmoregulatory capabilities of zander (Sander lucioperca) fingerlings in different salinities of the Caspian Sea

Osmoregulation capabilities of two size groups (1 and 2g) of zander, Sander lucioperca, fingerlings were investigated survival rate, plasma osmolarity, sodium (Na+), chloride (Cl-) ion concentrations and cortisol level within 0, 6, 24, 72 and 240 h after abrupt transfer from freshwater to 7 and 12‰ salinity. Also, some hematological parameters were measured at 240h. The plasma osmolarity and ion concentrations (Na+, Cl-) increased immediately after the transference to 7 and 12‰ salinity, reaching maximum at 72h in 1g and at 24 h in 2g fingerlings, and significantly decreased at 240 h, while the freshwater control group maintained almost constant during 10 days which showed lower than the salinity groups. The pattern of cortisol level changes was similar in two size groups after exposure to different salinities and it reflected stress of handling. There were no significant differences between hematological values of two salinity treatment groups than the freshwater control at 240h. The result showed, not only 2g zander fingerlings acted better than 1g in faced with salinity but also the fingerlings weighing 1g could survived and tolerate Caspian Sea water salinity up to 12‰. It is suggested that the release of zander weighing from 1g would help to restocking management of this species in the southern Caspian Sea

Effect of dietary estradiol-17β on growth performance, body composition and blood indices in Stellate sturgeon, Acipenser stellatus

This study was investigated the effects of dietary estradiol-17β (E2) on growth, body composition and blood indices in Acipenser stellatus. Fish (40.9 ± 1.1 g average initial weight; n = 60 per group) were fed with three different diets containing 0 (control), 25 and 50 mg kg-1 dietary estradiol contents to apparent satiation for seven months. The results suggested that growth rate were decreased as the E2 level was increased. No significant difference was observed in condition factor among dietary treatments. The highest survival rate was observed in fish fed control diet, but was not significantly different among the treatments (P>0.05). Body composition did not show significant changes among dietary treatments. Number of white blood cells and red blood cells, hemoglobin and hematocrit values were significantly decreased as the E2 levels were raised (P<0.05). Plasma biochemical parameters including glucose, total protein, cholesterol, triglyceride, calcium, and phosphorus levels were dose dependent with the lowest levels in control with the highest levels in fish treated with 50 mg E2. The results of the present study revealed growth suppression of dietary E2 and changes of blood indices with providing some basic information on the effect of estrogen hormone on physiology of sturgeon

Parasites of some bonyfish species from the Boojagh wetland in the southwest shores of the Caspian Sea

The Boojagh international wetland with a surface area of 80 hectares and 25 fish species is located in the southwest shores of the Caspian Sea (Guilan province, Iran), but there is no report about fish parasites in this wetland. In the present study, a total of 553 individuals of 8 fish species including Cyprinus carpio (n=71), Abramis bjoerkna (n=153), Carassius auratus gibelio (n=89), Esox lucius (n=39), Rutilus rutilus caspius (n=36), Rutilus frisii kutum (n=81), Scardinius erythrophthalmus (n=119) and Tinca tinca (n=4), were collected in October 2001 through November 2003. Eight parasite species were identified in the fishes consisting of 1 nematode: Raphidascaris acus (in E. lucius and S. erythrophthalmus); 1 cestode: Caryophyllaeus fimbriceps (in R. rutilus caspius and C. carpio); 2 digenean trematodes: Asymphylodora tincae (in T. tinca) and Diplostomum spathaceum (in all of the fish species except for T. tinca and S. erythrophthalmus); 2 monogenean trematodes:Tetraonchus monenteron (in E. lucius) and Dactylogyrus sp. (in C. carpio, A. bjoerkna and C. auratus gibelio); 1 crustacean: Lernaea cyprinacea (in A. bjoerkna, T. tinca and R. rutilus caspius) and 1 leech : Piscicola sp. (in R. rutilus caspius and C. carpio). The occurrence of R. acus in S. erythrophthalmus and also that of C. fimbriceps in R. rutilus caspius are reported for the first time as new host records

Effects of LHRH-A2 and chlorpromazine (dopamine antagonists) on inducing spawning in Caspian Kutum, Rutilus frisii kutum, from the southwest of the Caspian Sea

Caspian kutum, Rutilus frisii kutum, is one of the most commercially important fish species in the Caspian Sea, but there are few reports about the endocrinology of induced spawning in this fish. In the present study, 54 individuals of female broodstocks of Kutum were studied for quantity and quality of propagation index, during March and April 2007. Hormone treatments include: LHRH-A2 (1 µg kg-1bw;chlorpromazine (2.5 mg kg-1bw); LHRH-A2 + chlorpromazine (1µg kg-1bw+2.5 mg kg-1bw); CPE as a positive control (1 mg kg-1bw); Physiological saline as a negative control; and normal brood stocks without injection. For histological examinations, ovarian samples of non-ovulated females were fixed in bouin's fluid. The routine procedures of preparation of tissues were followed and the paraffin blocks were cut at 5-7 microns, stained with H&E and studied under light microscope. The results showed that the highest percentage of ovulated females belonged to group 1 without significant difference with positive control.There was a significant difference between ovulated females in the LHRH-A2, chlorpromazine and LHRH-A2 + chlorpromazine treatments (P0.05). Chlorpromazine could not be a potent dopamine antagonist and the microscopic observations of ovary in non- ovulated brood stocks showed that the oocytes in these treatments were in the final phase of IV stage

Effects of water temperature and migration time on some fecundity indices and fertilization rate of female Kutum, Rutilus frisii kutum,migratory to Shiroud River in the southwest Caspian Sea

Kutum, Rutilus frisii kutum, is an commercially important fish in the Caspian Sea. The fish enters the rivers leading to the Caspian Sea for spawning. One of these rivers is Shiroud River. In the artificial propagation process of Kutum, different factors are involved in quality and quantity of female broods eggs and also in the best temperature and migration time for spawning. The influence of temperature and migration time on some fecundity indices and fertilization rate of female kutum in Shiroud River was studied in the spawning season. In this study, 90 individual females were studied from February to May 2007. Averages of total length, weight and age were 43.26 cm, 832.08 g, and 4.41 respectively. Results showed that maximum egg diameter (1.86 mm), number of eggs per each gram of body weight (309.12), relative fecundity (56.21) and fertilization rate (95.82 %) were obtained from 5 to 20 April (15.95°C). Maximum ovary weight (201.00 g) and absolute fecundity of eggs (49987.18) were obtained from 6 to 20 March (17.74°C). Relationship between temperature and migration time and fecundity indices was linear and weak

Comparison of morphometric and meristic attributes of bream (Abramis brama orientalis), in Caspian Sea and Aras Dam Reservoir

Morphometric and meristic specifications of Abramis brama orientalis of the Caspian Sea and Aras Dam Reservoir was studied in the year 2002. For this purpose, 40 morphometric attributes, 16 meristic attributes and 37 specifications in relation to the proportions of speciality of morphometric attributes of the Abramis brama orientalis were evaluated from the two habitats. Anova, factor and discriminant function analyses were conducted on the data. According to results the average coefficient of variation in morphometric, meristic and proportion of speciality of morphometric attributes for Abramis brama orientalis of Caspian Sea was 22.85, 3.24 and 7.68 and for Abramis brama orientalis of Aras Dam Reservoir was 17.45, 3.53 and 15.27. The Abramis brama orientalis of the two areas showed meaningful differences in 35 morphometric factors, 6 meristic factors and 25 factor of proportion of the speciality of the age had significand differences (P<O.05). Factor analysis showed that the Abramis brama orientalis of the two habitats had 80.62% of changes in 7 factors of first morphometric attributes, 73.65% of changes in the 9 factors of the first proportion of morphometric specialities and 46.52% of changes in the 4 factors of the first meristic attribute. We showed that, fork length, standard length, proportion of head length to the standard length, number of scales of the lateral line, number of scales under the lateral line, number of scales above the lateral line, radius of dorsal fin and number of dorsal fins can be used to separate population of the fish from the two habitats. The first two factors of proportion of speciality of morphometric and meristic attributes causes total separation of the two populations. We found different in morphometric specialities between the two specialities of morphometric and meristic attributes. It is suggested that different environmental conditions have led to the differences in the populations of the fish in the Caspian Sea and Aras Dam Reservoir

Artificial spawning and fingerling culturing of European Catfish (Silurus glanis L. 1758)

The present study was conducted to survey the artificial spawning of European catfish (Silurus glanis L.) by synthetic hormones include Carp pituitary extract (CPE), Ovo fact [D-Ala6 des Gly10] GnRHa Ethyl amid in combination with domperidone diluted in propylene glycol, Human gonadotropin chryonic hormone (HCG) and LHRHa (des-Gly10, [D-Ala6] LH-RH Ethyl amide). In this research work 44 male and 72 female brood stokes that transferred to the Shaheed Dr Ansari hatchery and Sefid rod research station were studied on 2 years and injected with those stimulated maturation. Total length, total weight, gonad weight were measured to the nearest 0.1 cm, 1g and 0.01g respectively. The experiments were conducted using different doses of hormones on 4 treatments. In treatment CPE that brood stocks injected with 2.5, 3, 4 and 5 mg/kg/BW, the most responded (83.33%) was with 5mg/kg/Bw of CPE. The mean fertilization in this treatment was 92.5 4.51 and after that there are groups which were stimulated by 4 mg/kg/BW of CPE .In treatment ovafact that brood fish were injected by 10, 20, 30, 40 μg/kg/BW of this stimulation hormone showed 100 percent of fish ovulated in the group treated with 40 μg/kg/BW of ovofact. The mean fertilization rate was 86.08 6.27 in this group. 33.3 % of brood fish ovulated in the group that injected with 40 μg/kg/BW of LHRHa stimulation, but none of brood stock reached to spawning with injection of 30 μg/kg/BW of LHRHa. The brood stocks were injected by 800, 850, 900, 950 IU/kg/BW of HCG, only 33.3 percent of fish in groups that received 900 & 950 IU/kg/BW of this Stimulation hormone reached to spawning stages. According to our results and statistical analysis between trial treatments in percent of Embryo viability showed significant difference (P<0.05) between HCG treatment with Ovofact and CPE groups. This results indicates that embryo viability was better in CPE and Ovofact rate to LHRHa and HCG treatments. In the other cases include the working fecundity, fertilization percent, latency period of maturation, latency period of incubation eggs and ratio of weigh stripped egg to body weight did not show any significant difference (P<0.05) in experimental treatments for stripping the male brood stock of European catfish were injected by 3,4,5 mg/kg/BW of CPE, but not one of male brood fish didn’t reaches to stripping stage , so for eggs fertilization were used of milt from macerated Testes of dead males. So in anther experiment the male brood fish were injected by 5 mg/kg/BW CPE repeatedly at once every 5 days for Period 20 day’s period and milt were collected from of all of the males

A study on environmental pollutants (Organochlorine pesticides (OCPs), heavy metals, hydrocarbons and surfactants) in the southern part of Caspian Sea

At the present study, the environmental pollutants such as organochlorine pesticides (OCPs), heavy metals, hydrocarbons and surfactants were done during 22 months (Sept. 2009 through May 2011) located in southern part of Caspian Sea with longitude and latitude 48°-54° N and 36°-39° E, respectively. The aims of this study were to determine the seasonal pollutants matters in water layers and bed sediments of eight transect (24 stations) and the results are as follow: The maximum seasonal percentage range of OCPs were detected in spring water samples from 10, 50, and 50m depths such as (DDD, δ-BHC, heptachlor epoxide, endrin aldehyde),(DDD) and (aldrin, β-endosulfan) compounds about 62.5, 75 and 100%, respectively. The maximum seasonal residues fluctuation of OCPs were determined in spring water samples from 10, 50, and 50m depths such as aldrin (Babolsar station), aldrin (Tonekabon station) and heptachlor epoxide (Astara station) compounds about 5.03, 3.08 and 31.43 µg/l, respectively. The maximum percentage range of OCPs were detected in sediments samples from 10, 50, and 50m depths such as aldrin and α-BHC (winter), α-BHC (summer and winter) and aldrin (summer) compounds about 100, 75 and 87.5%, respectively. The maximum residues fluctuation of OCPs were determined in sediments samples from 10, 50, and 50m depths such as α-BHC (summer in Nushahr station), α-BHC (summer in Sefidroud station) and α-BHC (winter in Tonekabon station) and compounds about 5.96, 3.77 and 3.07 µg/l, respectively. The fluctuation and distribution of Total Petroleum Hydrocarbons (TPHs) concentration in different water layers samples were reduced from summer>spring> fall > winter, respectively. Also this trend occurred for bed sediments and reduced from winter > summer, respectively. The mean concentrations of TPHs in water samples of all seasons, regions, depths and transects were less than maximum permissible concentration (MPC). In this research, a comparison of TPHs with EPA standards shown that the desile range organic (DRO) was close to EPA standards such as TPHs and also 95 percent of water data were less than MPC. But gasoline range organic (GRO) concentrations in all stations were less than the amount of EPA standard. A comparison of TPHs concentration in sediments shown that the concentration of all stations were less than of national research council (NRC) range except west part. The maximum annual mean concentrations of Hg and Pb elements were detected in surface station (50m) at Nushahr and Amirabad transects. The most water data of Cd, Pb and Hg elements in comparison with critical concentrations with Europe, the USA and Japan standards were less than amounts of those standards. The distribution and abundance of Cd, Pb, Hg and Ni elements in water samples were detected 98, 96, 77 and 6%, respectively less than the ISQGs (Interim marine sediment quality guidelines) standards. In sediments samples, the mean and maximum concentration of Hg element detected in winter in comparison with ISQGs standards was more. But the concentrations of Cd and Pb in sediments samples of all stations were low and less than of ISQGs standards. The maximum concentration of linear alkyl benzene sulfonate (LAS) from spring through winter in Anzali (spring), Tonekabon (summer), Anzali (fall) and Nushahr (winter) were 0.07, 0.45, 0.145 and 0.087 mg/l, respectively. The maximum concentrations of LSA were detected in spring and fall in west part and summer and winter in middle part. But the lower concentration was occurred in west of southern part of Caspian Sea. According to standards of surfactants and comparison with LAS concentration of this study were less than the critical points

Determination of oil pollutant (water, sediment and fish) in the southern part of Caspian Sea

This study was conducted to determine 16 Polyaromatic Hydrocarbons (16 PAHs) concentrations in water (during four seasons) and surface sediments (during summer and winter) at eight transects (Astara, Anzali, Sefidroud, Tonekabon, Nowshahr, Babolsar, Amirabad and Turkman) in the southern of Caspian Sea in 20102011. 94 samples of water and 45 samples of surface sediments were collected at 10, 50 and 100 meters depths. In addition, 28 samples of fish (Cyprinus Carpio) were collected during winter and spring. All samples were prepared by Soxhlet and extracting processes and then determined using High Performance Liquid Chromatography (HPLC) instrument. Results of current study showed that mean concentration and standard error (±SE) of 16PAHs water were observed 232 (±77), 1268 (±808), 538 (±190) and 151 (±53) µg/l in spring, summer, fall and winter, respectively. In addition, annual mean contents and standard error (±SE) of 16PAHs water were registered 24.10 (±8.12) µg/l. The Hazard Quotation (HQs) were calculated more than unit and belong to Benzo(a)pyrene and Dibenzo(a,h)anthracene compounds. Mean concentration and standard error (±SE) of 16PAHs sediment were observed 0.77 (±0.23) and 1.21 (±0.64) µg/g.dw in summer and winter, respectively. Also, the annual mean contents and standard error (±SE) of surface sediments were observed 0.93 (±0.33) µg/g.dw. The Hazard Quotation (HQs) were calculated more than unit and belong to Fluoranthene, Benzo(a)anthracene, Chryseneand Benzo(a)pyrene. The annual mean contents and standard error (±SE) of edible tissue of Cyprinus Carpio mussels were observed 2.21 (±0.42) µg/g.dw. Annually, pattern of 16PAH compounds were obtained 10, 70, 12 and 8% for 3,4,5, and 6 rings, respectively. Four ring compounds had high content and percentage and 2 ring was not observed in all samples of water. Also, pattern of 16PAH in surface sediments were obtained 31, 56 and 14% for 3, 4, and 5 rings, respectively. Four ring compounds had high content and percentage and 2 and 6 rings were not observed in all samples of surface sediments during two seasons. Result of Diagnostic Ratios analysis (DRs) of sediments showed that the source of oil compounds were petrogenic and pyrogenic in summer and winter, respectively. Based on DRs in water and sediments were observed oil compounds were either petrogenic or pyrogenic with different percentage in the southern Caspian Sea. In conclusion, the results revealed that in the some transects the 16PAHs concentrations of water were above the threshold levels and more petrogenic (85%) sources which represented polluted condition in this area. 16PAHs concentrations of sediments were below the threshold levels and conditions for this region were showed unpolluted. Also, the Caspian Sea sediments were classified in Class 2 (Fair). According to results of the evaluation’s risks to human health associated with consumption of the mussels containing 16PAHs suggest that there is risk for humans