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A study on methanol herbal plant extract of garlic, green tea and Echinacea on immunity level of Mugil cephalus
Get PDFMedicinal herbs are non-specific stimulants for the immune response, as useful material for fish and other aquatic animals are known. 1080 grey mullet larvae with an average weight of g 0.75 ± 0.02 and an average length cm 4.40 ± 0.81 were purchased from Ramin port is located 5 km far from the fishing port of Chabahar. This research is based on nine treatments and control designed with 3 replications and a control treatment. Each 3 treatments with its replications dedicated to garlic, green tea and Echinacea. 38.7 ±1.85 micrograms per ml was highest lysozyme activity, phagocytosis rate (56 ± 1.55%) and respiratory burst (1.61 ± 0.18 absorbance at 620 nm) in the treatment with 100 mg of garlic extract per kilogram food was observed. The highest lysozyme activity by the extract of Echinacea was observed in treatment of 200 per million as 15.73 ± 1.13 mg green tea by 11.6 ± 0.3 were recorded in the same concentration. The highest activity of lysozyme (11.3 ± 0.7 micrograms per ml), the phagocytosis (33.3 ± 1.49%) and respiratory burst (0.57 ± 0.08 absorbance at 620 nm) in treatment green tea extract 200 mg per kg of food was observed. According to the results seems lysozyme activity and phagocytosis, which is considered an indicator of the safety of non-proprietary are influenced highly by diets containing garlic
A study on fishing status and some reproductive characteristics of Klunzinger’s mullet (Lize klunzingeri) in coastal waters of Khuzestan province
Get PDFBiological characteristics of Liza klunzingeri were studied in two coastal areas, Sajaphi and Bahrekan, of eastern Khuzestan during March to February 2007. Among total 1880 measured fish specimens, 947 specimens were analyzed. The mean value of Gonado-somatic Index (GSI) for the male and female fish were calculated as 0.96± 1.39 and 3.25 ± 3.26 respectively. The GSI value was highest in November and lowest in July. The mean value of condition factor (K) was 1.25± 0.14 in male and 1.21± 0.15 for female. The highest K value were observed in June and the lowest value in February. The lenght at first maturity regardless of sexuality, was found to be 14.5 cm and the time of spawning based on reproduction pattern were determined in Nov- Dec. The length-weight relationship were calculated as Y=0.024L^2.76 (n=226R2=0.72) for males, Y=0.011L^3.00 (n=444R2= 0.78) for females and Y=0.0208L^2.82 (n=670R2 =0.82) for total fishes and also it’s found significant in level length weight relationship in (P<0.05). According to biological characteristics and referring to American fisheries society (AFS) indices and Fuzzy logic expert system, Lize klunzingeri is classified as low vulnerable species
Assessing benthic health of hard substratum macrobenthic community using soft bottom indicators and their relationship with environmental condition
Get PDFThis study aimed to assess ecological quality status of hard substratum macroinvertebrates communities of the Caspian Sea with three ecological indices and their relationship with environmental factors. For this purpose, benthic communities of the Caspian Sea basin were studied seasonally during 2014 in 8 sampling sites. Temperature, salinity, dissolved oxygen; pH, nitrate, nitrite, silicate and phosphate were measured as environmental factors. The benthic classification indices AMBI (AZTI Marine Biotic Index), M-AMBI (Multivariate AMBI) and BENTIX (BENthic IndeX) were applied to assess the ecological status of the studied area. Results showed low dissimilarity based on species composition and abundance among seasons, while all seasons discriminated clearly based on environmental factors. In addition, AMBI index was more successful to assess ecological health of hard substratum in the Caspian Sea basin than M-AMBI and BENTIX. Furthermore, AMBI showed high sensitivity to environmental variation. Results indicated that temperature, nitrate, silicate, phosphate and nitrite were the most important factors in the composition and abundance fluctuation of hard substratum macroinvertebrates communities, respectively
Molecular and phylogenetic investigation of Chiromantes boulengeri (Decapoda, Brachyura, Sesarmidae) species from Arvand river
Get PDFIn this study, the molecular characteristics of Chiromantes boulengeri were investigated from intertidal waters of Arvand River, Minoo Island in 2014. For this reason, samples from intertidal zones of two areas across Minoo Island were collected and preserved in 70% ethanol, followed by transferring to the laboratory for further examinations. Genomic DNA was extracted using phenol- chloroform method and mitochondrial gene 16SrRNA was sequenced and compared with other species from GenBank NCBI. The morphological examinations using identification keys and phylogeny sequence results showed that all specimens belonged to Chiromantes boulengeri in the study area. Phylogenetic analysis revealed that there are mutations within C. boulengeri from two areas of Arvand River. It seems that, this species most probably is adapted to the different ecological conditions in this area
Detection coastal thermal fronts in the Persian Gulf and the Oman Sea using MODIS images
Get PDFTemperature fronts are important in marine studies. Sea fronts are sharp boundaries between different water masses. For this study different time series of MODIS level-3 thermal IR SST data from 2013-2014 has been processed and thermal fronts the of Persian Gulf and the Oman Sea (47.6°E to 67.7°E and 18°N to 31°N) region mapped using the method, the Canny algorithm and Gaussian filter. Monthly thermal front images of this region are mapped during the period of January 2013 to June 2014 are classified into Summer Monsoon (June, July, August, September), Winter Monsoon (October, November, December, January) and Pre Monsoon (February, March, April, May) periods and their characteristics are discussed here. The results show that high frequency of SST fronts was observed in the Oman Sea and Persian Gulf in October, November, December, January and May in 2013 year and January, November and December in 2014 year. The number of fronts increases since the beginning of winter to early spring and the beginning of fall, too. The remaining these fronts move with current toward the Arabian Sea and Indian Ocean at the beginning of the summer monsoon. Sustainable and cohesive front was seen near the Arvand River in the Persian Gulf that is presents in the cold months more. This front will disappear in the months of July, August and April 2013 and 2014. The other stable front is in the Oman Sea in southern Pakistan. Most of the front are presenting in the warmer months of June, September, October in 2013 and in June, August and October in 2014
Investigation of effect weight of parameters affecting the hydrodynamic coefficients in design of surface-piercing propellers
Get PDFHigh speed craft with the wide and various uses of entertainment, sporting, commercial and military, usually has a top speed of 30 knots. Due to the limitations of the design, use of propulsion system is a key issue, with regard to the desirable features surface-piercing propeller, their use in the propulsion system of the vessel, has been very useful. High efficiency, no restrictions to increase the diameter, resistance equipment supplied propeller removed, the proper functioning of cavitation, are examples of these features. To achieve the best efficiency and thrust requirements requires accurate determination of the coefficient of hydrodynamic thrust and torque. Given the importance of determining the coefficients and their dependence on various physical parameters and geometric, it is necessary to understand the effect of these parameters on the hydrodynamic coefficients, so in this study, experimental tests and collect data using sensitivity analysis, the weight of each parameter and the interaction of parameters surface-piercing propeller to evaluate the hydrodynamic coefficients on the propeller thrust, propeller torque, and therefore performance, is desired. Based on the results obtained, the parameters of step angle, skew and compared to other parameters, have the greatest impact in changing the propeller efficiency, while changing the ratio Immersion, the change will have little impact on efficiency and propelle
India: street vendors, fish markets and food security
Get PDFWhile women in fisheries cope with the challenges of changing market systems, persistent gender inequities threaten to impact livelihoods and food security
Population assessment, threats and conservation measures of marsh crocodile at Dasht River, Gwadar
Get PDFDasht River is the largest seasonal river in District Gwadar and Turbat which is fed by Nehang and Kech Rivers. The river and its tributariesare good habitat of Marsh crocodile (Crocodylus palustris). Population census of the species revealed that there is a sharp decline in their numbers and are some serious threat to crocodile at Dasht like predation of their eggs by feral dogs, shooting by local people, habitat destruction like construction of dams and agricultural activities, illegal smugglings of crocodile juveniles and frequent tropical cyclones/high floods in the area. There was an alarming decline in the populations during a period of 10 years. There were 99 crocs of the species in 2007-8 having 63 adults, 18 sub adults and 18 juveniles which reduced to only 25 crocs having 23 adults and only 2 juveniles in 2017-18.
The decline of adult population and absence of offsprings indicates that the reproduction is not taking place, which is a highly unhealthy and dangerous situation. The habitat degradation needs to be controlled. The current conservation program like might the species which is classified as endangered must be considered for a status of critically endangered species
Symbiotic association between Echinometra mathaei (Echinoidea: Echinometridae) and Athanas sp. (Caridea: Alpheidae) from Sunhera Beach, Karachi (Northern Arabian Sea)
Get PDFDuring a recent fieldwork conducted along the exposed rocky shores of Karachi revealed association between alpheid shrimp Athanas sp. and sea urchin Echinometra mathaei (de Blanville, 1825). Globally symbiotic relationships between shrimps and other invertebrates is a known phenomenon, whereas the association between caridean shrimp and sea urchin has been commonly reported since long. The current study describes taxonomic details of both the organisms. This is the first report on symbiotic association between alpheid shrimp and sea urchin from Pakistan