JOURNAL OF MARINE BIOLOGY
Year:2019 | Volume:11 | Issue:41|Papers Count:8

Study of fish food habits is effective to determine artificial feeding and design theories of food relations. For this purpose, food habits of catfish, Plicofollis dussumieri that lives in Tiab beaches, located in Minab between summer 1395 to spring 1396 was performed. Thirty specimens were caught in each season so a total of one hundred and twenty specimens were taken and morebiometric of specimens was performed. Samples immediately were placed on ice and transfered to the laboratory then study procedures of the abdominal contents was done. Biometric results showed that the mean weight of male and female was (1520± 30 to 1425± 25gr). Mean length of the male was (42. 7± 0. 18 cm) and female was (38. 3± 0. 07 cm). Average relative length of intestine was (2. 75± 0. 4 cm) in male and (2. 70± 0. 25 cm) in female. Results for gastric emptying index was 39. 16, so it showed that this species is relatively addictive. Based on stomach contents, 22 specimens were full, 51 specimens were semi-full and 47 specimens were empty. The highest stomach empty percentage was in autumn and winter, and the highest full percentage of stomach was observed in spring and summer. Based on food preference index, this species placed omnivores as fish and shrimp were the main, but crab, algae and cephalopoda were sub food. Overall season changes and availability of food items were the most important factors affecting in nutritional intensity and habits.

This research was carried out to assess the amount of the biomass and Catch Per Unit of Area (CPUA) and also to determine the distribution pattern of the haemulidae family in the northern parts equipped with trawl floor area cape of meydani ('58 ˚ 55) east To Govater (61° 25׳ ) east in the waters of the Oman Sea (Sistan and Baluchistan province) based on trawl survey results in 2013 by R/V Ferdows-1. The area divided to the 5 regions (A, B, C, D, E), with deep layer of 10-20 meters, 20-30 meters, 30-50 meters and 50-100 meters at a total 82 stations, were determined. Required information such as geographic location, depth, covered distance and silence were recorded. The fish caught after being unloaded on the deck were separated from the family and then counted and weighed and calculation of catch per unit area and live mass was performed. The highest biomass and CPUA of haemulidae was recorded approximately 439. 2 tons and 1213. 8 kg/nm2 in the stratum B and for depth layer of 30-50 m with value of 455. 9 kg/nm2 and the highest biomass for depth layer of 50-100 m with value of 405. 2 tones. Finally depth distribution chart and distribution map was drawn with Arcview-GIS software. The findings can be concluded that best region for hunting and main habitat for Haemulidae are B stratum and Preferential depth layer is 50-100 m, that Due to different biological and non-organic factors as hunting, temperature, salin

The aim of this study was evaluate tissue lesions caused by black gill disease and its causes in 85-80 days old Litopenaeus vannamei with an average weight of 13-15 g located in the Delvar shrimp rearing site from Bushehr province. Primary and secondary gill lamella was necrosis, central axis were not arranged and gill lamella swelling, epithelial cell necrosis along with karyorrhexis and pyknosis of gill lamella was observed in wet mouth examination and tissue sections. Also, Epistylis protozoan parasite were observed in gill tissue. The high prevalence of Epistylis protozoa (84. 58%) in gill tissue, indicates the proper condition of gill tissue for colonization of this parasite. Increased sedimentation of phytoplankton and folding on the gill tissues is considered as an exacerbating factor in the disease. Based on the results, it can be admitted that Epistylis protozoan parasite can be a factor cause of black gill disease in L. vannamei shrimp farms of Delvar shrimp rearing site from Boushehr province. On the other hand, black gill can be caused by several environmental and infectious agents, including fungal and bacterial agents, but in this study were not detected any other pathogen. Hence, in further studies, more comprehensive research is needed to isolate and identify the primary cause of the disease for the management of health and treatment.

The present research was carried out with the aim of measuring the levels of the heavy metals Cu, Zn and Fe in the muscle tissues of the Acanthopagrus cuvieri in Bushehr port. To this end, 30 A. cuvieri with an average of 840. 73± 156. 101 gr and 34. 28± 3. 089 cm were hunted in spring 2018. The samples were washed with distilled water and a portion of the pure muscle tissues was isolated. After dehydrating the tissues and discharging the water in the intertextual space, 0. 5 gr of the powdered tissue sample was isolated and the acid digestion of the samples was carried out using 5 ml of concentrated nitric acid. To measure the levels of the heavy metals Cu, Zn and Fe a (Perkin Elmer 3030) atomic absorption spectrophotometer was employed. The results of measuring the concentrations of the heavy metals Cu, Zn and Fe in the muscle tissues of the A. cuvieri suggested that the mean and standard deviation were (6. 32± 0. 22, 61. 12± 0. 14 and 4. 86± 0. 36) mg/kg dry weight during spring, respectively. The results of this study revealed that the Cu and Zn concentration in muscle tissues of A. cuvieri in study station were lower than the levels permitted within the standards of World Health Organization (WHO), Food and Agricultural Organization (FAO), National Health and Medical Research Council (Australia) (NHMRC), Ministry of Agriculture and Forestry and Fisheries UK (MAFF). But Fe concentration in muscle tissues of Acanthopagrus cuvieri in study station was higher than the level permitted within the standard of Food and Drug Administration (FDA). Hence, these two species will not pose severe general health risks to human consumers.

This study was conducted to evaluate the resistance to antibiotics in the western white shrimp propagation centers on pathogens of Vibrio bacteria. In Iran, the most important bacteria in the shrimp are the vibrio species. In Bushehr Province, due to the high efficacy of erythromycin antibiotics, streptomycyne oxytracycline and tremitoprim in bacterial diseases, were selected as the species. The bacterial strains of Vibrio harvey and Vibrio aliginolyticus were isolated from the replication centers and the resistance of the bacteria was investigated using disk diffusion method. Isolation of bacteria and identification by biochemical and biological tests and comparison of pH and different temperatures were investigated. All three Vibrio harvey bacteria isolated from the three replication centers A, B, C, relative to the antibiotic erythromycin, were semi-sensitive, resistant and susceptible, respectively. Three antibiotics were susceptible to trimethoprim for antibiotics. Vibrio oliginolyticus isolated from three proliferation centers was resistant to streptomycin. But the isolated bacteria from center C were resistant to semi-sensitive erythromycin and the two bacteria A and B. The results showed that the highest antibiotic resistance to streptomycin at the first stage and then erythromycin is seen at the next stage. The results showed that the pH of the antibiotics was low at pH 6 and increased to 7 by increasing pH. Antibiotic resistance with temperature is also significant (P<0. 95). The analysis showed that temperatures of 35 oC are the most appropriate temperature for Vibrio bacteria. Assessment in aquaculture also has many challenges. In particular, this assessment of antibiotics is one of the key elements in the health of the community.

Algae are among the aquatic organisms that are severely exposed to increasing levels of pollutants, which are becoming a concern in marine ecosystems. Heavy metals are among the compounds for which their increase in high levels causes problems in the structure of algae communities in aquatic ecosystems. In this study, the effect of different concentrations of Nickel (1. 5, 3, 4, 6, 8, 12, 15 mg/l) and cobalt (1. 5, 2, 3, 5, 6, 8, 10 mg/l) on chlorophyll a and the carotenoid level of microalga Nannochloropsis oculata was investigated for 72 hours. The EC50 of nickel and cobalt were determined according to the OECD 2011 protocol. The results of acute tests showed that EC50 of nickel and cobalt was 6. 5 mg/l and 5. 3 mg/l, respectively. Overall, the results of this study showed that nickel caused toxicity in higher concentrations compared to cobalt. Furthermore, nickel and cobalt heavy metals significantly inhibited the growth and reproduction of N. oculata. However, these heavy metals had lower effect on ceratoid contents.

Thyroid hormones [Triiodothyronine (T3) and thyroxine (T4)] are also known to play an important function in biological processes such as growth, sexual development, osmoregulation, metamorphosis, temperature tolerance, migration, oxygen consumption, and metabolism in different fish species. The objective of this study was to examine the effects of T4 injection on growth performance, and reproduction performance in sterlet sturgeon (Acipenser ruthenus). Three treatments with two replicates and 5 fish (initial weight 707. 97 ± 37. 15 g) for each group were considered. The experimental treatments included: control (coconut oil), low dose of T4 (T1; 1 mg T4/kg body weight + coconut oil) and high dose of T4 (T10; 10 mg T4/kg body weight + coconut oil). Four intraperitoneally injections of sterlet sturgeon female were performed every 2 months over a 170 days period. Growth performance, reproductive parameters and larval growth performance were measured at the end of the experiment. The results showed fish treated with high dose of T4 were noted higher growth rate compare to other groups. Fish in T10 had higher fertilization rate (73. 4 ± 0. 6%) compared to control group (46. 1 ± 2. 2%) (P < 0. 05). Greater number of eggs per gram was achieved in control group (134. 3 ± 8. 6). Also, higher hatching rate was obtained in T1 (82. 00 ± 2. 2%) and T10 (72. 3 ± 5. 0%), respectively (P < 0. 05). Higher larval weight gain showed in T10 (0. 052 ± 0. 0 g) and control group (0. 027 ± 0. 0 g), respectively. . In conclusion, injection of 10 mg T4/kg body weight in sterlet sturgeon can perform positive effects on reproduction in broodstock and larval growth performance.

Cell culture involves a process where cells from different types of tissues are replicated in vitro Tissue culture and development of the cell lines from fish is used to isolate viruses, toxicology, Oncology, cellular physiology and gene expression. In this study, primary cell culture of kidney were prepared using a total of 10 Rutilus kutum with average weight of 12 ± 1 g and the mean length of 11 ± 1 cm were by explanting method. Tissue Pieces were explanted in cell culture flasks containing L-15 medium with antibiotics (penicillin, styrpthomycin) under different temperature conditions (21, 24 and 28 ° C) and fetal bovine serum levels (5, 10 and 20%) then cultured in two ranges ofpH (6. 8 and 7. 2). The results showed that the preparation of primary cell culture of kidney tissue of Caspian white fish (Rutilus kutum) at 24 ° C and 20% of the fetal bovine serum was better than other treatments and the cell migration rate was calculated as 88. 37%. So far, 8 passages from these cells have been carried out, which could lead to the production of a cell line from the kidney of Rutilus kutum in the near future.