The effects of endosulfan on P450 1A gene expression, antioxidant enzymes activity and histopathological alterations in liver of Persian sturgeon (Acipenser persicus Borodin, 1987)

The effects of 14 days exposure to sublethal concentrations of endosulfan (10 and 40 μg L−1) were investigated in mRNA- P450 1A expression, antioxidant enzymes (SOD and CAT) activity and histopathological alterations of Persian sturgeon (Acipenser persicus) fingerlings with weights of 3–5 g. The results illustrated that the relative mRNA- P450 1A expression level significantly increased (P < 0.05) compared to the control group. Highest significant increase (P < 0.05) was observed on the first day, then decreased towards day 14 of exposure. The SOD and CAT activity showed a significant increase in fish exposed to different concentrations up to day 7, then activity decreased on day 14 in fish of all treated groups. Although signs of tissue lesions were observed on day 4, they increased from day 7 and reached the highest level on day 14. The magnitude of all changed studied parameters (gene expression, enzymes and histopathological) follows a concentration-dependent manner. © 2016 Blackwell Verlag Gmb

Karyology of pikeperch (Sander lucioperca)in the south Caspian Sea

Pikeperch (Sander lucioperca) is one of the economic fish species in the Caspian Sea, with no official report on its chromosome preparation and karyotype formula. For the metaphase preparation, 29 fry specimens of the fish weighting 10-25g each were used. Colchicine 0.01% at 0.7ml/100g of fish weight was injected in the muscular tissues. After 180 minutes, kidney and gill tissues were removed and hypotonized in KCL 0.075 M for 40 minutes, fixed with Carnoy mixture for 18-20 hours, homogenized and dropped on the slides, and stained with Giemsa 20% for 30 minutes. The prepared slides were swept by objective X100 light photomicroscope. The results showed that the chromosome number of this species is 2n = 48 and the chromosome arms is NF = 76. The karyotype formula of the species was found to be 2n = 1m + 13sm + 4st + 6a. Comparing the results of the study with those of other researchers showed that the pikeperch chromosome number in the South Caspian Sea is similar to the fish in other parts of the world but the type of chromosomes and karyotype formula is different

Induction of triploidy in grass carp Ctenopharyngodon idella Valenciennes, 1844: comparison of cold & heat shocks

Triploidy in grass carp, Ctenopharyngodon idella Valenciennes, 1844, was induced on fertilized eggs to compare cold and heat shocks. Two simplified methods explained for verification of triploidy in grass carp. The cold shock (7 ˚C) was given in three treatments for 30 min starting 2.0, 2.5 and 4.0 min after fertilization. In cold shock, the start point (2.0 min after fertilization) showed the highest rate of triploidy (60.9%). Heat shocks were given at 38 ˚C, 40 ˚C and 42 ˚C, at 4.0 min after fertilization and lasted for 1.0 min. Produced larvae using heat shock 38 ˚C showed 10.8% triploidy, but no signs of triploidy were seen in other heat shock treatments. Verification of triploidy in grass carp was carried out using karyotyping and measurment of erythrocytes surface area and volume in fingerlings. Ratio of erythrocytes dimention and the size of their nuclei in triploids to diploids was 2.35 and 1.80, respectively. Comparison of results obtained from the application of cold and heat shocks indicated that cold shocks are more effective than heat shocks in the induction of triploidy in grass carp

Application of microsatellite markers to study the genetic structure of stellate sturgeon populations (Acipenser stellatus Pallas, 1771) in the south Caspian Sea

Population genetic structure of stellate sturgeon (Acipenser stellatus) in 197 adult specimens from four fishery regions along the Iranian coastline of the southern Caspian Sea was investigated using microsatellite markers. Out of 15 microsatellite primers, 11 loci were produced, in which 10 of them were polymorphic and 1 was monomorph. Totally, 184 alleles were identified and on average 13.1 alleles per locus were found (ranged 8 to 18 alleles). All sampled regions contained unique alleles. Average observed and expected heterozygosity was 0.667 and 0.854, respectively and significant genetic differences between 4 regions were observed (p≤0.01). Deviations from Hardy-Weinberg equilibrium were found in most cases. Population differentiation test was modest and significant (p≤0.01). Based on FST estimate (p≤0.01), more than one population of stellate sturgeon is identified in the south Caspian Sea. Therefore, fishery management for restocking and conservation of gene pool is highly recommended

Karyotype analysis in white bream (Blicca bjoerkna transcaucasica) from north coast of Iran

Preparation of chromosome spreads and karyotype analysis in Blicca bjoerkna transcaucasica were carried out using 0.01% solution of colchicines and Phytohaemagglutinin (PHA) (20 µg g-1 body weight). The gill and kidney tissues were collected and let to stand in a hypotonic solution of 0.075 M KCl and then treated with a fixative (Carnoy's solution) in three steps. The chromosomes spreads were then stained with 5% Giemsa solution for 20 min and examined under a light microscope. Appropriate metaphase plates were photographed in order to prepare karyotype. The size of the chromosomes (short and long arms), relative length of chromosomes and centromere index were calculated. Chromosome spreads from gill tissue cultures which were colchicine treated with PHA, had a well defined size, shape and number of chromosomes for karyotype analysis. Based on the 76 metaphase plates studied, chromosome count in 59 metaphase plates was 2n=49.74±0.25. By arranging homologous chromosomes beside each other the chromosome formula was calculated as 6 pairs of Metacentric, 10 pairs of Sub-Metacentric and 9 pairs of Sub-Telocentric (2n=6M+10+Sm+9St) and the chromosome arm number (NF) was 100. The largest chromosome in this species was a pair of metacentric chromosomes. On the basis of the number and type of chromosomes, the karyotype obtained for this species conformed to the findings of other researchers, but the chromosome formula was different, which could be attributed to the existence of different populations for this species

Cytogenetic study on Artemia from Urmiyah Lake

To determine the chromosome numbers of artemia brine-shrimp in Urmiyah Lake (Azarbaijan-e- Gharhi province), cytogenetic studies were carried out on artemia cysts. In order to identify the collected samples, each sample of cysts, first incubated in sea water (35 ppt salinity) and then to determine the reproduction mode, the cyst samples were feed with Dunaliella tertiolecta, for three generations (F3) up to adult. The results showed that there were two types of anemia in terms of reproduction mode, namely bisexual and parthenogenesis. Chromosome spreads were prepared from freshly hatched nauplius squashing method. The results of counting 100 metaphases plates from bisexual artemia and 35 metaphases plates of parthenogenetic specimen, it was found that the number of chromosomes in these 2 types of artemia were the same, 2n=42. In these population, very small chromosomes with metacentric, submetacentric, telocentric and acrocentric types were observed. Karyotype formulas of bisexual and parthenogenetic artemia were determined as 2n=30 M / SM+12 A/T and 2n=32 M / SM+10 A/T, respectively. All studied samples in Interphase stage lacked and chromocenter. Due to very small size of chromosomes, it was difficult to do precise determination of the type of chromosomes and in this regard various C.banding experiments were performed. Also, since chromosomes in artemia lacked any chromocenter, the differentiation of chromosomes based on the types of C.banding was impossible

Karyology study of Spirlin (Alburnoides bipunctatus) in Zabol region

The chromosomal spread and karyotype of Spirlin (Alburnoides bipunctatus) from Zabol region were identified using tissue squashing techniques with injection of 0.5ml/100g body weight of 0.01% Colchicines solution in fish fingerlings. Kidney and gill tissues were extracted and chopped in KCl 0.075M for 30 min and fixed in Carnoy solution in 3 stages. The chromosomal spreads were stained in 20% Gimsa for 20 min. From 34 chromosomal spread counts, the results showed diploid chromosome number of this species 2n=50. Karyotype composed of 9 metacentric, 14 submetacentric and 2 acrocentric or subtelocentric chromosome pairs, and the number of chromosome arms (NF) was determined as NF=96

An investigation on the micropyle number in the ova of the strugeon species in Caspian Sea

The micropyle number in the ova of sturgeon species from the South Caspian Sea was investigated. The study was conducted on female broodfishes of three species of sturgeon (Persian sturgeon Acipenser persicus, Stetates sturgeon A. stellatus and great sturgeon Huso huso) included 44 Persian sturgeon, 13 stellate sturgeon and 8 great sturgeon specimens. Fifty eggs were randomly collected from each broodfish and the micropyle number of totally 3250 eggs was determined. Out of 44 Persian sturgeon used, 14 specimens were collected from the south-east Caspian region (Golestan Province, Shaid Marjani Center) and 30 were from the south-west Caspian region (Guilan Province, Shahid Dr. Beheshti Center). The stellate sturgeon specimens were taken from the south-west and the great sturgeon specimens from the south-east Caspian region. The obtained result showed that the mean micropyle number in Persian sturgeon caught from the south-east Caspian region was 8 whereas in those caught from the south-west region was 9. There was no significant difference (p>0.95) in the micropyle number of Persian sturgeon collected from the south-east and south-west regions. The mean micropyle number determined for stellate and great sturgeon was 5. The outer diameter of the micropyle in the Persian, stellate, and great sturgeon were 22 μm, 17 μm and 19 μm respectively

Determination spawning season and changes in reproduction cycle of Schizothorax zarudnyi and condition factor in Hamoon Lake

Schizothorax zarndnyi is one of the most economic and endemic species, which are found in rivers and triple lagoons of Hamoon. In this study, reproduction cycle, type, season and optimum temperature of spawning period was studied from July 1998 to June 1999. The maximum GSI was 7.9-9.6 in March and April with 14-18°C mean temperatures. The minimum GSI was 0.92 in May. Variation in GSI values shows that reproduction has annual cycle which begins in May and ends in April of the next year. From October significant increase of oocyte diameter and GSI were observed in 2 different groups, while oocyte distribution observed only in one group in May. The rate of HSI had flucatuation, during resting period of ovule (from May to September) and from October simultaneously with significant increase of GSI, the HSI increased and continued to January and decreased in March and April. The condition factor, was changed during reproduction cycle and it was minimum in March (0.92). Concerning these investigation, Sch. zarndnyi is a total spawner and showing a synchronous ovary

Comparison of genetic variation of ship sturgeon (Acipenser nudiventris) in the southern Caspian Sea and Ural River using PCR-RFLP

Genetic variation of ship sturgeon (Acipenser nudiventris) from the Caspian Sea was investigated using NADF15/6 gene and PCR-RFLP analysis. A total of 80 specimens of the fish were collected from the south Caspian Sea and the Ural River from Kazakhstan. mtDNA ND5i6 gene was amplified by polymerase chain reaction (PCR) digested using 39 Endonucleases Restriction Enzyme. Of the 39 enzymes, five showed polymorphism. Totally, ten composite haplotypes among 80 specimens were detected. Haplotype AAAAA showed maximum frequency (57.5%) whereas haplotypes BBAAA and BABAA showed minimum frequency (12%). Haplotype AAAAB was recognized specifically in Ural River specimens. Average haplotype and nucleotide diversity was 0.8516 and 0.007 respectively. Compared to other sturgeon species living in the Caspian Sea, nucleotide diversity of Ship Sturgeon was much lower (0.007). This may be due to smaller population size of this species. Monte-Carol simulation using 1000 interaction did not show any significant differences between haplotype distribution of the fish sampled in the south Caspian Sea (X^2=35.48 , P=0.74). However, we detected a significant difference between haplotype of Ship Sturgeon from Ural River and the south Caspian Sea. We conclude that Ship Sturgeon from Ural River is different from the fish in the south Caspian Sea and suggest CfrI31 enzyme as a molecular marker for population differentiation in the Caspian Sea