مجله علوم و فنون دریایی
سال سیزدهم شماره 4 (زمستان 1393)

Among more than 600 fish species in Persian Gulf، Soles are considered as one of the most economically important species. These fish is different from other fishes in morphological، functional and structural organs and like many other flatfish are less well known. The present study was designed to investigate the histological structure of gonads of Sole (Euryglossa orientalis) in two breeding and rest seasons. 40 Sole fish were collected from Zangi estuary (located in Mussa creek in the north of Persian Gulf) in early July and early October (non- breeding and breeding seasons) 2013. After biometry، gonadal tissues were dissected and weighed to determine Gonadosomatic Index (GSI). Then fixed in Bouin ''s solution. Histological specimens were transported to the histological laboratory. Tissue sections were prepared according to conventional methods include dehydration، clearing and paraffin. And then were cut down to 5 micron sections and stained. These tissue sections were studied by light microscopy. The result showed that different stages of germ cells in both male and female gonads. Although in breeding season mature cells were noticed، GSI index of testis and ovary in Sole showed significant difference between the two seasons.

The “Coastal and Marine Ecological Classification Standard” is one of the new and complete approaches to understand of marine habitats. We were applied Biotic Cover and Surface Geology as the two components of the classification to the northern intertidal stretch of Qeshm Island. Considering the extent and geomorphology of the area، 9 sites were designated. Density and temporal distribution of biotic community were determined using 0. 5×0. 5 m quadrate، and sediment was sampled up to 15 cm below the surface to determine its type and material. Totally 32 codes were determined for 40 habitats (biotopes)، and their positions were displayed on map. Our result show that the biotope diversity decreases westward. Also، the highest and lowest numbers of species were observed in sandy and muddy-sand substrates، respectively. It seems that habitats distribution is mainly determined by the substrate type، but other factors can also affect this distribution.

In this study، effects of BPA on erythrocytic nuclear abnormalities (ENA) stimulus (MN Test) and liver DNA integrity (DNA Unwinding Assay)، in male yellowfin seabream (Acanthopagrus latus) were investigated. For this reason، fish received intraperitoneal injections during a period of 2 weeks with 10، 50، 100 and 150 µg g-1 week-1 of BPA dissolved in coconut oil. Solvent controls received the coconut oil whereas controls were not injected. The fish were sampled on day 0، 7 and 14. In order to evaluate cytotoxicity of BPA presented in blood، the erythrocytic nuclear abnormalities (ENA) frequency in yellowfin seabrem was determined. Our results demonstrated a significant increase in fish micronuclei frequency after the treatment with bisphenol A in comparison to the control groups and in dose dependent manner. In addition، the rate of liver DNA integrity was tested using the DNA alkaline unwinding assay. Results showed a decrease in the rate of liver DNA integrity in treated fishes after 7 and 14 days of BPA exposure in comparison to the control group. In conclusion، results of the current project indicated that BPA has high genotoxic and/or cytogenotoxic potential. It could be concluded that Micronucleus test and DNA strand breaks can be used as sensitive cellular and molecular indicators of exposure to genotoxic BPA.

In this study، 4 different food diets were examined for feeding white worm which were studied. Results showed that suitable moisture for growth and development of white worm was 50 - 70 % that their biomass reached to a 675 g/m2 during 90 days. But it decreased significantly at moisture lower than 45 % and upper than 65 %. White worm had similar growth both in acidic and basic area. White worm biomass reached to 576g/m2 during 90 days in basic area but reached to 568 g/m2 in acidic that was maximum at pH 6. 4 - 7. 6، while its growth decreases at pH lower than 6 and higher than 8. In this study، Azola used as food for white worm in amount of 60%، wheat meal 25%، and wheat bran 15% that caused to more growth in worms and their biomass reached to 533 g/m2 during 90 days. Although biomass of worm fed with mixture of potato 30%، carrot 3%، wheat meal 25% and wheat bran 15% reached to 584 g/m2، but biomass of worms were fed with mixture of potato 60%، wheat meal 25%، and wheat bran 15% reached to 576 during 90 days. Economically، cost production of Azola was lower in comparison to other diets. Biochemical decomposition of worms fed with mixture of Azola، wheat meal and wheat bran showed more protein (33 %) than others. Based on results Azola can be used as a suitable and commercial replacement for white worm food diets.

In this study، the effect of vegetation on the reduction of the transmitted wave height and beach vegetation to absorb the force of the waves has been studied. Tests for the two layouts with rectangular and triangular spaced 5 × 5 and 10 × 10 cm، 3-state within 10، 30 and 40 cm، 5 sloping beach.، 3، 5، 7 and 10% and 5 wave height of 5/1، 3، 4، 6 and 8 cm were used. In total، 325 different cases have been investigated. 25 of them were been done in no vegetation condition. Dynamic pressure is measured at several points on the coast by a pressure transducer. The force exerted by the waves on the beach of the fuselage has been measured using electronically force meters (load cell) installed in the part of the flume is made movable. The results show that the effect is more rectangular than triangular arrangement of the reduction in wave height.

This study was done to identify larval stages and biodiversity of Dendrobranchiata planktonic communites in artificial reefs of Khuzestan coasts (Bahrekan area in Northwest Persian gulf) for one year from May 2011 to April 2012 monthly basis. Sampling was conducted using a plankton net with a spring 300 micrometers. Totally، from two superfamily: Penaeoidea and Sergestoidea، 3 families: Sergestidae، Luciferidae، Penaeidae were identified. From Penaeidae family، Metapenaeus affinis، Penaeus indicus and Parapenaeopsis stylifera species، from Luciferidae family، Lucifer hanseni specie and from Sergestidae family، Acetes sp specie were identified and introduced. Also larval density of identified species in different months and stations are calculated and determined Metapenaeus affinis specie (With the average of number per cubic meter in 1029±830) from Penaeidae family account for larval density is maximum in September. Finally، two abundance peak was observed that the first peak was in September and the second peak was in November. The maximum of relative frequency percentage in Penaeoidea superfamily related to mysisI stage and 62 percentage. The results obtained indicate that the artificial structures are well managed nursery area for Penaeidae shrimp. The maximum average value of Shanon-wiener index was in November (1. 36) due to the presence of all species in the same month. Simpson index was lowest in November، which confirms the above conclusion.

This research was performed to introduce a standard protocol for enrichment of Artemia urmian with Canola oil. Artemia urmiana nauplii were enriched at three densities (50000، 100000 and 200000 nauplii L-1) and three concentrations of Canola oil (0. 1، 0. 2 and 0. 3 g L-1). Their effects were evaluated on survival، total length and profile of fatty acids at 6، 9، 12، 15 and 18 hours after the onset of enrichment. Cysts of A. urmiana were hatched according to the standard method. A. urmiana nauplii were stocked at above densities in 7 L cylindrical containers. Canola oil emulsion was added at concentrations of 0. 1، 0. 2 and 0. 3 g L-1 at the beginning and 12 hours after the onset of enrichment. The results of analysis showed that enrichment of A. urmiana with 0. 3 g L-1 Canola oil at 100000 nauplii L-1 for 18 hours was considered as the best treatment. Artemia nauplii enriched in this treatment had significantly higher levels of (n-3) PUFA and survival and minimum total length comparing to other treatments. The treatment had significantly higher levels of (n-6) PUFA than all treatments except treatment with a density of 50،000 nauplii L-1 with 0. 1 g L-1 Canola oil for 18 hours.

In this research، gut contents of white leg shrimp Litopenaeus vannamei were investigated for 113 days culture period at earthen ponds in Delvar of Bushehr، by sampling every 15 days. Results showed that artificial food had highest weight percentage in gut contents (foregut، midgut، and hindgut) following in order by detritus، zooplankton، phytoplankton، and macro-benthic. In the beginning of culture period، macro-bentic were observed in larval gut contents while other food items were throughout culture period. The maximum occurrence of detritus in gut contents was at 26 and 40 days-old larvae while highest phytoplankton was obtained at 86-days-old larvae in end of culture period. The zooplankton had approximately similar amounts throughout culture period in different parts of gut، while macro-benthic only observed at 26-old-days larvae with maximum amount at foregut and midgut. The mean highest gut fullness attained at foregut (0. 95 %) and lowest at hindgut (0. 20 %). The dominant color of gut content was green-brown in all parts of gut that could be due to consumption of natural pond products. This study illustrated that most consumed food items in L. vannamei was prepared by natural pond foods. In addition، detritus and plankton have most important in L. vannamei during culture period.

This study was conducted to identify fish larvae from the upper pelagic layer of Oman Sea، off east shore waters of Hormozgan Province during May 2011. Sampling was obliquely conducted using Bongo Bongo-net plankton sampler with 500 µ of mesh sizeby Thai Prantlay 10 Vesselle. In each station،abiotic factors (Temperature، Salinity and PH) were recorded. Upper pelagic waters of Oman Sae had less fish larvae in compare to nursery grounds like creeks and estuaries. In total 125 specimens were collected and examined. They were belonging to 8 families. Engraulidae، Mullidae and Sillaginidae were dominant families، which included 45% of total fish larvae abundance. There were 14 stations. At stations 3، 10 and 13 the biodiversity was in highest levels. The maximum abundance was 36 larvae per 10 m square of sea surface at station 12. In some stations، there was no fish larvae and in total، most of larvae were in post flexion level.