فصلنامه بوم شناسی آبزیان
سال سوم شماره 1 (پیاپی 301، تابستان 1392)

Although sex steroids play an important role in many physiological processes including reproduction in vertebrates¡ there is a few information about the effects of these hormones in coral-reef fish reproduction. Determination of fluctuation of these hormones would be very useful in reproductive studies. In this study¡ 120 specimens Abudefduf vaigiensis including 47 females and 34 males were captured by rod and line from the northern coast of Gheshm Island¡ Persian Gulf. The plasma levels of testosterone during the gonadal development were determined through ELISA method. The mean of testosterone were 2.59± 0.78 in autumn (min 2.57 in July¡ max 3.24 in August) and 2.30 ± 1.57 ng/ml in winter (min 1.43 in November¡ max 2.97 in Desember) for females¡ which the values of November were significantly less than July. Also in August and August values were significantly more than September. The testosterone mean in males were 2.28± 0.65 in autumn (min 2.01 in September¡ max 2.67 in August) and 1.90 ± 0.88 ng/ml in winter (min 1.57 in November¡ max 2.10 in Desember). The mean values of November were significantly less than the others month. The results showed that the value of testosterone due to its role in gonadal development during vitellogenesis¡ in different months has been significantly changed. The levels of this steroid increased as in August the high level of this hormone is measured in both sexes.

Low survival at early stages of life is of great concern for fish culturists. Considering the effects of herbal immunostimulants on innate immune response and growth improvement of aquatic animals, the impacts of a native herb of Hormozgan province named Zhumeria majdae extract on growth indices and immunology of catfish fingerlings Pangasianodon hypophthalmus with mean weight of 1.27±0.24 were investigated. Fish were fed diets supplemented with Z. majdae extract at 0 (control group), 150 (treatment 1), 300 (treatment 2) and 600 (treatment 3) mg/kg diet for 45 days. After the feeding trial, fish growth, hematology and immunology parameters were analyzed using Duncan test. Fish growth parameters including FER, DGI and SGR were not significantly different between treatments at days 15, 30 and 45. Survival percentage in all treatments supplemented with herb extract was 100%. The highest haematocrit level was at treatment 3 (46.67±7.64%), The highest number of RBC (3.10±0.6×106) and WBC (7.40±0.3×103) and also the highest amount of total protein and albumin was at control group, the highest amount of hemoglobin, MCV and MCH was at treatment 1 and the highest NBT and MCHC value was at treatment 2. In white blood cell differential count, the highest percentage of neutrophil was observed in control group, the highest percentage of lymphosyte in treatment 1 and the highest percentage of monocyte in treatment 3 .The amount of lysozyme was significantly different with the highest amount at treatments 3 and control, respectively and the lowest in treatment 2 (p

Microorganisms can be used in order to break down and clean any type of a specific class of compounds which are found in petroleum and its related products. In this study, the rate of biodegradation of petroleum hydrocarbons by five isolated cyanobacteria from oil polluted region of south part of Iran has been studied. These include Anabaena ISC55 ¡ Nostoc ISC26¡ Nostoc ISC32 ¡ Phormidium ISC24 and Leptolyngbya ISC25 ,that after growth in the specific growth medium and subsequently cultured in BG-11, was aerated for 28 days in the presence of crude oil .The amount of remained residual hydrocarbons before and after this period and the altering of expressed proteins were analyzed by GC method and SDS-PAGE , respectively. The presence of cyp110A2 gene that belong to monooxygenase P450 enzyme family was analyzed by PCR method. The results showed that the total amount of hydrocarbons remained in mentioned species were, 11.16 %, 41.46 %, 84.45%, 13.38% and 98.44% respectively. Changes in protein expression were clearly detected in all species, too. In addition, PCR results indicate the presence of cyp110A2 gene only in Anabaena ISC5 and Phormidium ISC24 .We concluded all five samples are appropriate candidates for biodegradation of crude oil specially Anabaena ISC55 and Phormidium ISC24 that showed the best results.

This investigation was carried out to study the effect of probable contaminants existing in the Southern Pars region on density and species richness of macrobentic communities under tidal area in Nayband Bay and to determine the environmental parameters caused by human activities which influence the Benthic communities of this region. Three stations were selected that were different in terms of susceptibility to activity of oil and gas industries in the region. Station 1 was considered as the control station (Haleh) station 2 and station 3 as a station with moderate susceptibility and very high susceptibility, respectively. Sampling from sediment in each station was carried out in two winter and summer seasons (2009 – 2010) by Van veen grab with area of 0.04 m2. Further, water sampling from the depth of 1.5 meter was done using Rotner sampling bottle. The highest individuals (2172) and species (68) per m2, Shannon index (3.54) and Pielou uniformity (0.84) were observed in the control station and then in the stations 3 and 2, respectively. The highest were obtained in the control region. Also, the results showed a significant correlation between changes of environmental factors and changes of heavy metals and of population structure of macro benthic in different stations. In all three stations, significant correlations were observed between environmental factors including total hardness, reduction potential, amount of phosphate and copper and structure of macro benthic (Pw= 0.70). The present research suggested that disorders caused by industrial and human activities somehow affect environmental and thereby have influences on benthic communities.

Gulf of Oman, in the summer, is influenced by the southwest monsoon winds of India, and Jask protected area, which is ecologically and economically very important, is located in the northwestern area of this gulf. In this study, sampling of sediments was done from 2009 to 2010, in three station (mouth, mid and end) of Markazi creek (located in Jask city), by 0.04 m2 Van Veen Grab. Water physicochemical parameters (including dissolved oxygen, salinity, temperature and pH) of the water near the seabed, as well as sediments grain size, and total organic matter (TOM), were measured at each station. The relationships between diversity and abundance of macrobenthos and biological and non-biological factors, were studied in sampling seasons (premonsoon, monsoon and postmonsoon). A total of 14425 pcs per m2, belonging to 64 species of macrobenthos were counted and identified. In total, Gastropoda with 22 species and Bivalves with a frequency of 9125 pcs per m2, had the highest diversity and density of macrobenthos, respectively. The results of this study showed that, the spatial and temporal variation of macrobenthos in this area affected by climatic fluctuations are due to the Indian Ocean monsoon. The maximum and minimum densities of macrobenthos were identified at postmonsoon season (8075 pcs per m2, equivalent to 58.24% of total species), and during monsoon season (2766 pcs per m2, equivalent to 17.21% of total species), respectively. Results of calculating the diversity index, Shannon-Wiener, showed that the maximum and minimum value of this index were observed at premonsoon, end station (1.03), and postmonsoon, mid station (0.41), respectively.

Platypoecilus macuhatus is a Viviparous fish belonging to subclass teleosteons (F. Poeciliidae). Oogenesis in this fish can be divided in tow following stage I: Clear Ooplasm with few organells is covered with a layer of follicular cells. Apearence of the first yolk droples also Occurred in this stage. Stage II: microvilli forms and then a radial layer appears between them. The development of Covering layers is due to the activity of both the oocyte a follicular cells. In addition the the peripheral vacuols appear in this Stage. StageIII: Differentiation and strengthening of covering layers. Continued and the follicular cells take columnar shape. Yolk storage of ooplasm also is increased. StageIV: in this stage ooplasm is with Yolk substance, the nuclear membrane is broken apart and as a result of oocyte growing, its membrane takes a smooth shape, and the mikrovilli length is decreased. Althoughin the process of oocyte development the desmosomes don’t exist after breading they appear in between the follicular cells. The fully grown oocyte is protected with four layers, where each layer play its specific role physiology and protectiveness.