Feeding habits and trophic level of Himantura gerrardi (Elasmobranchii; Dasyatidae) in northern Oman Sea: effects of sex and size class

The feeding habits and trophic level of Himantura gerrardi were studied according to sex and size classes of 80 individuals obtained using bottom trawl between May and December 2014 from the Oman Sea. Collected specimens were divided into three size classes (small58 cm) based on disk width. Prey was identified in seven main zoological categories, where crustacean and polychaetes were the dominant in diets, indicating this species is a demersal dwelling species. No significant differences were observed between sexes, but size classes showed significant differences in their diets. Also, results showed a decrease in feeding overlap between size classes with an increase in disk width, suggesting that intraspecific competition reduced, which allows the coexistence of different size classes. Trophic level was positively correlated with the disk width, which was lower than 4.0 for both sexes and different size classes, placing it in an intermediate trophic level

Short communication: First report of mangrove whipray Himantura granulata (Macleay, 1883) from the Persian Gulf, Iran

Dasyatidae is primarily a marine subfamily, which is most common in shallow tropical waters. The species of this family are distributed worldwide; from tropical to warm temperate; Atlantic (Including the Mediterranean Sea), the Indian, and Pacific Ocean. Six genera, Dasyatis (synonyms Trygon and Urolophoides), Himantura, Pastinachus (synonym Hypolophus), Pteroplatytrygon, Taeniura, and Urogymnus, with about 68 species are included in this family. In the Persian Gulf, some members of family Dasyatidae are important species in terms of number and biomass. This family is represented by three genera (Dasyatis, Himantura and Pastinachus) and seven species, although they have been frequently confused by forms and colors. ... In this study, first report of H. granulata from the northern Persian Gulf with some morphometric measurements is given

Investigation of population genetic structure of common carp (Cyprinus carpio) in the south Caspian Sea using mtDNA method (PCR-RFLP)

The population genetic structure of common carp (Cyprinus carpio) was examined on 260 specimens from Tajan and Gorgan Rivers, Gorgan Gulf, Anzali Lagoon and other regions in east, middle and west of south Caspian Sea. DNA was extracted from fin tissue by phenol-chlorophorm method with a concentration of 50-100 nanograms. PCR was performed using ND-3/4 and ND-5/6 genes. The PCR products of samples were digested by 15 restriction endonuclease enzymes. The digested products accompanied with standard marker (50 pb). To measure fragment size, samples were run on a 6% vertical poyacrylamide gel. The fragments were visualized by silver staining of the polyacrylamide gel. Statistical analysis of data was performed by Reap software. We detected 14 and 12 different haplotypes in ND-3/4 and ND-5/6 genes of common carp. The mean values of haplotype diversity among populations were 0.59 and 0.48 and the average nucleotide diversity was 0.06 and 0.03 for ND3/4 and ND5/6 genes. Also, the mean values of nucleotide divergence among populations were 0.05% and 0.02%, respectively. The haplotype distribution was not significantly different between Mazandaran and Guilan coasts, Mazandaran and Golestan coasts, Golestan coast and Gorgan Gulf and Gorgan River (P<0.05), but this divergence was significantly different between Guilan region and Anzali Lagoon, Guilan and Golestan coasts, Tajan and Gorgan Rivers (P<0.05). We found a significant genetic divergence between some of the samples such that three genetic groups of common carp were identified in the southern part of the Caspian Sea

Molecular diversity of Symbiodinium spp. within six coral species in Larak Island, the Persian Gulf

Reef-building coral harbor communities of photosynthetic taxa of the genus Symbiodinium (zooxanthellae). The genus Symbiodinium is currently classified into nine genetic clades (A–I). Various corals harbor different Symbiodinium clades; some show specificity to a single strain. Coral and their zooxanthellae are sensitive to environmental stresses. In the Persian Gulf, coral reefs are subject to harsh environmental conditions including extreme temperatures and high salinity. This is the first study to use clade specific primers to clarify the diversity of Symbiodinium in each coral species of Larak Island. For this purpose six coral species were collected at two different locations in Larak Island. After DNA extraction, PCR amplification was performed using clade specific primers. The results showed that multiple Symbiodinium clades are hosted by most coral species. In addition, among thirteen obtained Symbiodinium sequences, the frequency of either tree [sic] clades, A, C and D was almost the same. Corals species may contain different clades of Symbiodinium depending on the region and on the tolerance characteristics of each clade. Thus, knowledge of zooxanthellae diversity associated with scleractinian can contribute to a better understanding of the sensitivity of corals to environmental conditions

Effects of Chlorella vulgaris on blood and immunological parameters of Caspian Sea salmon (Salmo trutta caspius) fry exposed to Viral Nervous Necrosis (VNN) virus

In the present study, the effects of Chlorella vulgaris on blood and immunological parameters of Caspian salmon (Salmo trutta caspius) before and after exposure to Viral Nervous Necrosis (VNN) virus were examined. In this regard, four treatments in triplicate were chosen. Groups included one control and 3 treatments (T1, T2 and T3). Fish in control group, T1, T2 and T3 were fed diets supplemented with 0, 1×10^8, 2×10^7 and 3×10^6 chlorella/450 g of food respectively, for sixty days. In addition, a virus supernatant was prepared from infected wild golden grey mullet (Liza auratus) and used for virus challenge of S. trutta caspius. Virus was injected intraperitoneally and blood samples were collected before and 14 days after the challenge. Immunological (IgM, C3, C4, total protein, respiratory burst, albumin and lysozyme) and changes in blood parameters (RBC, WBC, Htc, Hb, MCH, MCHC and MCV) were also measured. Results showed that C. vulgaris could act as a natural immunestimulant. Also, the alteration trend in hematological and immunological parameters showed that experimental fish could be considered to be resistant to VNN virus after exposure and fish treated with C. vulgaris were more resistant in comparison to those in the control group. The dose used in T1 (1×10^8 chlorella/450 g food) was the most effective approach with significant differences

The relation between environmental parameters of Hormuzgan coastline in Persian Gulf and occurrence of the first harmful algal bloom of Cochlodinium polykrikoides (Gymnodiniaceae)

Cochlodinium polykrikoides was bloomed in the Persian Gulf for the first time in September 2008, started from the Strait of Hormuz and then spread out towards the northern parts covering most of the areas of the Gulf and lasted 8 months. In order to find out environmental conditions during the bloom, a monthly sampling program was carried out in seven surface stations in 2008-2009. At each station, three samples (triplicates) were collected for phytoplankton analysis and also one sample for environmental analyses, including salinity, chlorophyll a and nutrients. Blooms of C. polykrikoides were observed with a seawater temperature of 20.1 to 31.0 °C, salinity 37.0-40.1 ppt and nutrient concentration ranges during the bloom and red tide were 0.064-0.707 mg/l nitrate + nitrite and 0.001-1.66 mg/l phosphate, respectively. Maximum of C. polykrikoides abundance was measured 26 × 106 cells L-1 in October 2008. Kruscal wallis test demonstrated a significant difference in densities and chlorophyll-a in different months and seasons not in different stations. This study showed increase of temperature (>31.0 °C) stopped bloom and red tide due to C. polykrikoides in both the eastern and middle sampling stations but in the western stations was determined decrease in nutrient amounts as the major factor therefore increased nutrient of coastal waters, and environmental conditions could have efficacy the occurrence of this dinoflagellate

Evaluation of ecological status of the Persian Gulf inshore waters (Hormozgan rocky bottoms) using macrophytic communities and a macroalgae biological index, EEI

Marine benthic macrophytes (seaweed and seagrasses) are key structural and functional components of some of the most productive ecosystems of the world. They absorb nutrients through their surface directly from the marine environment and thus they are very important biological elements for the estimation of ecological status, representing reliable indicators of coastal waters. The aim of this study was to assess the ecological status and trophic level of Hormozgan rocky bottoms according to Ecological Evaluation Index (EEI). Sampling was done bi-monthly at seven stations at the intertidal rocky shores, west of Hormozgan Province. In this study a total of 63 species were identified, of which 15 species from seven genera belonged to green algae; 16 species from five genera belonged to brown algae; and 32 species from nine genera belonged to red algae. Coverage data of macroalgae and EEI indicate a high level of eutrophication for Saieh khosh, and Bostaneh. They are classified as zones with bad and poor ecological status, respectively. Also it has been proved that concentrations of biogenic elements and phytoplankton blooming are higher in these zones. The best values of the estimated metrics at Tahooneh and Michaeil could be explained with the good ecological conditions in those zones and the absence of pollution sources close to those transects. The values of abundance of macroalgae and EEI indicate moderate ecological conditions for Koohin, Lengeh and Chirooieh

A new method for venom extraction from venomous fish, green scat

Scatophagus argus argus (Green Scat) is a pretty aquarium fish. Its hard spines are venomous and can cause painful injury. In this study 60 specimens of Green Scat were collected periodically from coastal waters of Boushehr (south of Iran) from May 2011 to April 2012. Anatomical features of venomous spines were investigated. Scat venom was extracted from the spines in a new manner for keeping the specimens alive. The nature of venom was tested by SDS-PAGE. Ethical issues and animal welfare principles such as rapid and instantaneous anesthetizing, post operation disinfection and fast recovery of the specimens was practiced in order to minimize the complications. This method enhanced the purity and quantity of venom as demonstrated by 12 separated proteins in electrophoresis. New ethical issues were developed to surviving the specimens and prolong viability as well

Spatial and temporal patterns of benthic macrofauna in Gorgan Bay, south Caspian Sea, Iran

We quantified the distribution, abundance and assemblage structure of macrofauna at 22 stations in Gorgan Bay, seasonally in 2012-2013. Also, depth, temperature, salinity, DO, TOM and sediment particle size were measured in each station. The highest concentration of TOM was measured near the western littoral zone (10.22) while the mouth part and north-eastern area was characterized by the lowest values (2.65 % and 4.69). A total of 31658 individuals belonging to 12 families and 14 species were identified. Polychaeta with 3 species was the most dominant group in terms of abundance. The four most abundant taxa making up 85% of all specimens were Streblospio gynobranchiata, Tubificidae, Hediste diversicolor and Abra segmentum. The maximum density (7,893 ind/m^2) was obtained at station 1 while the minimum (1,777 ind/m^2) was observed at station 16. The western area was characterized by the highest species diversity (H', 1.94) and the stations 10, 8 and 7 were characterized by the lowest diversity indices (H', 0.72, 0.77 and 0.87, respectively). The PCA showed that water parameters with more temporary variations had a greater significance in explaining the system variability, and a not marked but evident difference between the two parts of Gorgan Bay was observed and supported by nmMDS test. So Gorgan Bay presents transitional macrobenthic assemblages that are spatially distributed along substrate gradients but it seems that the coastal ecosystem of the south Caspian Sea and mouth-eastern part of Gorgan Bay is very dynamic and some species are forming a metapopulation toward western sites

Hydrogel nanoparticle encapsulated plasmid as a suitable gene delivery system

To facilitate the delivery of genetic material, the use of appropriate carriers such as polymers is necessary. Nanoparticles comprising of chitosan-alginate polymers were formed through pregel preparation method. Chi/Alg nanoparticles had a mean Z-Average diameter of 161.8 nm and mean zeta 29.3 mV, respectively. The ability of plasmid-complex in preventing DNA migration showed Chi/Alg nanoparticles have great capacity to maintain plasmid. The efficiency of nanoparticles for transfection of pEGFP-N1 plasmid in the cultured HEK 293 cells was measured by flow cytometry. Cell viability assays indicated that nanoparticles had no toxic effect on HEK 293 cells after 4 or 24 h. Our suitable candidate for gene delivery would be alg/chi nanoparticles.Для облегчения доставки генетического материала необходимо использование подходящих носителей, таких как полимеры. Наночастицы, состоящие из хитозан-альгинатных полимеров, были получены методом подготовки прегеля. Chi/Alg наночастицы имели средний диаметр 161.8 нм (Z-Average) и средний zeta-потенциал 29.3 mV. Отсутствие миграции ДНК во время электрофореза комплексов плазмиды с наночастицами показало, что Chi/Alg наночастицы могут удерживать плазмидную ДНК внутри комплекса. Эффективность наночастиц для трансфекции плазмиды pEGFP-N1 в культивируемые клетки HEK 293 была измерена с помощью жидкостной цитометрии. Тесты на жизнеспособ-ность клеток показали, что наночастицы не имели токсичного эффекта на клетки HEK 293 через 4 ч или 24 ч. Наночастицы Alg/Chi являются подходящим кандидатом для доставки генов