Egyptian Fish Research Articles

Biogenic Silver Nanoparticles Synthesis from New Record Aquatic Bacteria of Nile Tilapia and Evaluation of their Biological Activity

The current study investigates the isolation identification of bioactive strain from fish collected from El-Burrllus region in Egypt. The objective of the current study is to identify and assess the biological profile of a new record strain in Egypt Bacillus maritimus. The molecular identification of the selected promising isolate and phylogenetic analysis confirmed the accurate identity of the isolate as Bacillus maritimus. The novelty of the present study was not due to only to the fact that the Bacillus maritimus isolate was the first record from brackish-water Egyptian fish gut, but also due to the fact that there is no previous study on the bioactivity of Bacillus maritimus and their efficiency as biogenic nanoparticles synthesis. The bioactivities for the Bacillus maritimus were investigated through different biochemical assays as antioxidant, anti-inflammatory and antimicrobial activity against six of the tested human pathogens namely; Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 8739, Enterococcus faecalis ATCC 29212, Pseudomonas aeruginosa ATCC 15442, Klebsiella pneumoniae ATCC 13883 and Streptococcus pyogenes ATCC 19615. Bacillus maritimus bacteria were grown in nutrient broth for 24 h at 37°C and the optical density was determined at 600 nm using the UV-visible spectrophotometer. The optical density (OD) of the broth was adjusted to 0.5 with sterile phosphate-buffered saline, pH 7.4 (PBS). the bacterial isolate showed antioxidant, and anti-inflammatory activities. In addition the bacteria showed great reducing agent ability as a biogenic agent for the silver nanoparticles. The phytochemical screening of the Bacillus maritimus isolates have showed varieties of bioactive groups in addition to total phenolic compounds, flavonoids, tannic acid, carbohydrates, sulfated polysaccharides, total proteins and lipids. This study highlighted also that the Bacillus maritimus isolate could also produce novel secondary metabolites. The current study report for the first time the Bacillus maritimus in Egypt. Further studies are needed to isolate and characterize more bioactive strains from Egyptian Fishes that could possibly act as novel bioactive compounds source of medical and agricultures importance.

Chemical quality of some fresh water fish in Egyptian markets

Total ninety random meat samples of fresh fish of Nile tilapia, Bagrus bayad and Clarias gariepinus (thirty of each) were collected from different Egyptian fish markets to be examined for their chemical quality indices to determine their fitness for human consumption. The results showed that the pH value was (6.32±0.01, 6.38±0.02 and 6.29±0.02), TVB-N (mg/100) was (14.54± 0.51, 12.71± 0.43 and 16.76± 0.46), TBA (mg malonaldyde/kg) was (0.82± 0.05, 0.57 ± 0.03 and 0.91± 0.06) and TMA (mg/100) was (6.19± 0.23, 5.49± 0.21 and 6.75± 0.19) in the examined samples of Nile tilapia, Bagrus bayad and Clarias gariepinus, respectively. So, it was appeared that the Clarias gariepinus samples were higher in their pH, TVB-N, TMA, TBA values than other examined samples. All examined samples were fit for human consumption except one Clarias gariepinus sample (3.33%) was unfit due to increasing its pH value than the limit of acceptability. This study shows superiority of Bagrus bayad were more than Nile tilapia followed by Clarias gariepinus samples in their chemical quality indices. So, we recommend proper handling of fish from catching till eating to preserve their human consumption fitness.

Bio - Economic study of the potential development of fisheries in Lake Manzala

The research aimed to study the determinants of fish production in Manzala Lake, study the seasonal movements of fish species, and show that the area of the water area of Manzala Lake did not exceed 0.7% of the total water area of Egyptian fisheries, but it contributes about 16% of the total Egyptian fish production, respectively, and about 14 . 2% of the total Egyptian fish income. It turns out that the annual fish production in Manzala Lake is directly related to the numbers of boats, the numbers of fishermen and the fish prices, and inversely with the average annual yield of the fisherman. It is clear that the fish production in Manzala Lake fisheries exceeds the seasonal average for the fall semester from the seasonal average for the rest of the seasons of the year to being the breeding and spawning season for the fish as well as the autumn months are actual fishing months where the hunter stays for long periods in the lake, while the average for the spring is the lowest for the rest of the seasons. The necessity of continuous follow-up in the treatment of incoming agricultural wastewater for the lake, and the continuous cleansing of the Bogus lake opening and guarding it from the thief of fry, with continuous review of the maximum allowed number of fishing boats operating in the lake according to technical and economic bases.

Occurrence and molecular identification of Anisakis larval type 1 (Nematoda: Anisakidae) in marketed fish in Egypt.

Anisakidosis is a zoonotic infection caused by members of the family Anisakidae. The presence of anisakid larvae in fish poses risk for humans and dissuade consumers from purchasing infected products. Although fish constitute important component of Egyptian diet, the prevalence of anisakid larvae in marketed fish in Egypt is not well described. Furthermore, the species of anisakid larvae is not defined in most of the available studies due to the over reliance on morphological analyses. The aim of the current work was to assess the prevalence and intensity of anisakid larvae in three common marketed fish in Egypt (Atlantic herring, Mediterranean horse mackerel and Atlantic mackerel) and to determine the species of the isolated larvae using morphological and molecular methods. Light and scanning electron microscope (SEM) analyses revealed the details of the isolated larvae. However, partial sequencing of cytochrome oxidase subunite-1 (mt cox1)gene revealed that all larvae isolated from Atlantic herring and Mediterranean horse mackerel belonged to Anisakis simplex sensu stricto with prevalence of 87.1% and 83.3%, respectively, whereas Atlantic mackerel harbored Anisakis typica with a prevalence of 42.8%. The Mediterranean horse mackerel demonstrated the highest larval mean intensity (n = 20 larvae/infected fish). This study highlights the importance of these fish as potential reservoirs for human anisakiasis in Egypt and possiblyin other coastal countries.

دراسة اقتصادیة لمحددات الإنتاج السمکی لبحیرة البرلس

The search aimed to study the determinants of fish production in Burullus Lake, study the seasonal movements of fish species in it, and estimating fish stocks .The results show that the area of the water area of Lake Burullus did not exceed 0.7% of the total Egyptian fisheries water area, but it contributes about 19% of the total Egyptian fish production, and about 18.2% of the total Egyptian fish income. The annual fish production in Burullus Lake related directly to the numbers of boats, the numbers of fishermen and the fish prices, and inversely with the average annual yield of the fisherman. It showed that fish production in Burullus Lake increases in summer and autumn, and decreases in winter and spring. The results indicated that about 65%, 80% of the changes in the total fishing capacity of Burullus Lake due to the change in fishing effort, and the results indicate a doubling of the rate of catfish production, either for the total fishing capacity in the lake or for tilapia fishing capacity, The study recommended the necessity of the continuous purification of the lake’s bogus slot and guarding it from the thief Fry and continuous review of the maximum permissible number of fishing boats operating in the lake according to technical and economic bases.

AN ECONOMETRIC ANALYSIS OF FISH FOOD SECURITY IN EGYPT

The problem of fish food security is represented in insufficient strategic stocks of fish, especially in light of the increasing demand for fish, and lower production than consumption. The research mainly targeted the study of the situation of fish food security in Egypt, in addition to a set of sub-goals, which are the most important that the estimation of both the strategic stock of fish and fish food security coefficient in Egypt, studying of the most important factors affecting fish food security, studying of future expectations for fish food security, This is in addition to studying the problems that Obstruct the continued increase in fish production. The research relied on achieving goals on the use of qualitative statistical methods and economic equations for estimating both strategic stocks and security coefficient for fish. As Quantitative statistical methods were used, which are represented in using the simple and multiple regression method to estimate the functions of consumption, production, import and export of Egyptian fish, as well as food security coefficient in order to determine the most important variables that affect it by building an econometric model that explains the determinants of food security of fish. The double logarithmic model was the best model used in terms of economic logic and statistical significance, and Autoregressive and Integrated Moving Average (ARIMA) model was used to forecast production, consumption, imports and food security coefficients for fish until 2025. In addition to using the statistical method, One-way Anova- Analysis of Variance, to test the differences between a number of independent groups that represent problems that impede the continued increase in fish production, as well as the use of the least significant difference method (L.S.D) to arrange the elements of each problem. By estimating the growth rate of fish production and consumption, the fish food gap and the average per capita share, it was found that the growth rate of each of them took an increasing general trend during the study period, where the annual growth rate is estimated at 5.4%, 4.9%, 2.8%, and 2.7% for each of them, respectively. It was also found that the quantity of the surplus in fish attained about 0.9 thousand tons on average during the study period, and this surplus is very small, not enough consumption per day. It is also clear that the fish food security coefficient reached about 0.00073 on average during the period (20002018) and this indicates a decrease in the fish food security rate. The forecast values of the fish food security coefficient have shown that the fish food security coefficient tends to decrease from about 0.00076 in 2019 to about 0.00073 in 2025. And by studying the most important variables that affect fish food security in Egypt through the three basic functions, which are the fish demand function, the fish supply function, and the fish food security coefficient function, of the Simultaneous model, according to the economic logic and statistical significance, Increase in both national income (x13), imports of fish (Y3t), local production of fish (Y1t) by 1%, the food security coefficient of fish increases by 0.04%, 0.102%, 0.49% for each of them respectively, and when increasing Consumption (Y2t) by 1%, the fish food security coefficient decreases by 0.67%. This has proven the significance of the variables at the level of significance 0.01, as it turns out that by increasing exports (Y4t) by 1%, the food security coefficient decreases by 0.01% and this decrease is statistically significant at the level of significance 0.05. A stratified random sample was chosen according to the cognitive and functional level, with the problems and obstacles of continuation of increasing fish production in Egypt. The sample was of those interested in the field of fish wealth. The problems were identified and divided into five categories which are: environmental problems, financing and production problems, marketing problems, problems related to scientific research, administrative problems. The study resulted in several recommendations, the most important of which are: Increasing the expansion of culture operations in floating marine cages. Increasing investment orientation for fish production from its various sources and providing financial support to small fish producers. Close control of the various pollution image processes of natural resources, overfishing, offensive fishing, and fishing fry and limiting their spread to preserve biological stocks.

تقدير الدورات الموسمية وأهم العوامل المؤثرة على الإنتاج السمکي بمصايد البحر الأحمر في مصر

تقدير الدورات الموسمية وأهم العوامل المؤثرة على الإنتاج السمکي بمصايد البحر الأحمر في مصر

A large-scale outbreak of botulism associated with a traditional celebratory Egyptian fish dish in five governorates - Lower Egypt, 2019: a teaching case-study

A large-scale outbreak of botulism associated with a traditional celebratory Egyptian fish dish in five governorates - Lower Egypt, 2019: a teaching case-study

Isolation and characterization of Mycoplasmas from some moribund Egyptian fishes

Mycoplasma is associated with fatal diseases in human, animals, and fish. Mycoplasma of aquatic origin has not been thoroughly studied. The current study has shed the light on isolation and characterization of unique piscine Mycoplasma isolates retrieved from diverse geographical locations across the Egyptian state. Mycoplasma spp. was isolated using specific culture media. Mycoplasma was identified using the morphochemical tests and then confirmed molecularly by PCR of the 16S rRNA gene. The results indicated that the incidence of Mycoplasma from Cyprinus carpio, Oreochromis niloticus, Aulopiformes synodontida, and Clarias gariepinus were 33.33%, 16.36%, 8.108%, and 6.45%, respectively, while Mugil cephalus were negative for Mycoplasma isolation. Mycoplasma was detected only from gills and swim bladder of affected fish. Biochemically, the isolated Mycoplasmas were grouped into two clusters. Mycoplasma cluster 1 (35 isolates) and Mycolplasma cluster 2 (7 isolates). Mycoplasma cluster 1 was positive for tetrazolium reduction while Mycoplasma cluster 2 was negative. The phylogenetic tree of partial sequences of 16S rRNA showed that both clusters were grouped in one branch and separated from other Mycoplasma spp., suggesting that both clusters are belonging to one species. Interestingly, all fish Mycoplasma isolates were PCR negative for both Mycoplasma mobile and Mycoplasma monodon using specific species primers. This result confirmed that these two clusters belonged to unspecified Mycoplasma species, for which the temporary names Mycoplasma cluster 1 and Mycoplasma cluster 2 were designated. Pathogenicity trials of both Mycoplasmas clusters revealed that all inoculated Nile tilapias were susceptible to the unspecified Mycoplasmas.

Estimating the value of investments and imports for achieving food security for fish

We research current scenarios to estimate the value of the investments and imports needed to achieve different levels of food security for fish in Egypt. We use the strategic stock estimation equations, the food security coefficient, the distribution of Bernoulli, and the standard errors at 95% confidence. The results are as follows. The strategic stock of fish reached 376,350 tons. With local consumption of 1.71 million tons in 2015, the fish food security coefficient was estimated at 0.22. The relative importance of the contribution of local production of fish security ranged from 14.05 to 20.95% at 95% confidence, while that of imports ranged from 1.15 to 8.05% at 95% confidence. Achieving full fish security requires an increase in production by 1.09 million tons to at most 1.62 million tons and an increase in fish imports from 88,760 tons to at most 621,350 tons, both at 95% confidence. The value of additional investments at a 10% discount rate to achieve full fish security ranged from at least 6.28 billion pounds to at most 9.35 billion pounds, while the value of the increase in fish imports ranged from at least 1.41 billion pounds to at least 9.85 billion pounds at 95% confidence.

Economic Study of the Foreign Demand Determinants for Egyptian Fish

The main objective of this research is to study the determinants of Egyptian fish demand during the period (2000-2018). The most important results of the research are the following: 1- Increasing the quantity and the value of Egyptian fish exports, with an annual growth rate about 18.8%, 20.4% for each of them, respectively. 2- The Egyptian fish exports depend on fresh and chilled fish export by 80%, live fish and ornamental fish by 8.55%, fresh and chilled molluscs by 6.04%, frozen fish by 3.37%, salted, dried and smoked fish 1.24% 0.43% shrimp and crustaceans of various types 0.43% processed and sliced or chopped fish, 0.32%. 3- Italy, Lebanon, and the United Arab Emirates are the most important foreign markets for Egyptian fish exports, as the value of Egyptian fish exports to these markets represents about 19.2%, 17.4%, and 8.2% of the total value of the average Egyptian fish exports during the study period. 4- The presence of an apparent comparative advantage in exporting Egyptian fish to foreign markets, where the value of this indicator increased from 59 in 2014 to 83 in 2018 5- The presence of a comparative price advantage for Egyptian fish in the Italian, the Lebanese, and the Emirati markets, where the price ratio index reached about 1.2, 1.4, and 1.8 for each of them, respectively. 6- A decrease in the penetration rate of Egyptian fish in the Italian market, which amounted about 0.5, while it was high in the Lebanese and French markets, which amounted about 11.3, 6.6, in the two markets, respectively, as a general average for the period (2013-2018). 7- The components of the Egyptian fish exports are characterized by the geographical concentration factor, where the index value reached about 0.62 in 2013 and continued to increase and approach the correct one until it reached 0.72 in 2018. 8- The decrease in the commodity diversity of Egyptian fish exports, as the value of this indicator was weak, which amounted about 0.63 in 2018. 9- The most influencing factors on the quantity of Egyptian fish exports during the study period between the determinants of global demand for Egyptian fish are both the record number of fish production in Egypt (X1), as well as the Egyptian trade policies towards fish exports (X8) as this indicates export development Egyptian fish. 10- Each of the problems and the productive technological obstacles and the marketing technology and the obstacles that relate to the nature of the export process and its procedures, and the obstacles that relate to foreign markets represent a major challenge to the access of Egyptian fish to the global market.

Occurrence and molecular characterization of zoonotic Anisakis simplex sensu stricto and Anisakis pegreffii larvae in retail‐marketed fish

AbstractThe study aimed at investigating the occurrence and molecular characterization of zoonotic Anisakis larvae in imported, retail‐marketed smoked herring (Clupea harengus) and frozen mackerel (Scomber scombrus) in Egypt. A total of 154 fishes (84 ready‐to‐eat smoked herring and 70 frozen mackerel) were collected. The prevalence of Anisakis larvae Type I in the whole specimen of smoked herring and frozen mackerel was 19.05 and 42.86% with mean intensities of 4.71 and 1.83. While the prevalence in muscles was 8.33 and 5.71% with mean intensities of 4.29 and 5, respectively. The sequencing of 11 larval PCR products from fish muscles revealed the presence of two zoonotic species; Anisakis simplex sensu stricto and Anisakis pegreffii. The recovered strains showed high identities to GenBank Anisakis isolates of fish from the North Sea, nearby waters and from China. More surveillance studies are recommended on those areas to ensure food safety and minimize public health risks.Practical ApplicationFrozen fish imports by Egypt have been growing significantly since 2009 to cover the progressive elevation in fish consumption there. Anisakis is one of the commonly reported zoonotic parasites infecting humans through fish consumption. This study provides important information on the prevalence and molecular characteristics of zoonotic Anisakis species in edible muscles of imported, retail‐marketed frozen mackerel and ready‐to‐eat herring fish in Egypt. The study outlined some recommendations to reduce the public health risks from that biological hazard.

Microbial Causes of Summer Mortality in Farmed Fish in Egypt

Bacterial diseases are responsible for sever mortalities and morbidities in cultured Nile tilapia in Egypt in various fresh water fish farms and the increase of water temperature in summer has a significant effect on mortalities. A total number of 100 clinically diseased Nile Tilapia (Orechromis niloticus) were collected alive randomly from Abbassa, Elsharkia (Central Laboratory for Aquaculture Research) Egypt, to identify the bacterial pathogens affect that fish. Samples were isolated from liver, kidney, spleen, eye, ulcer and brain. The isolated fish pathogens were identified as Aeromonas hydrophila, Ps.fluorescense, Ps.putida and V.cholera by their morphological characteristics, biochemical tests, Antibiotic sensitivity test and polymerase chain reaction test as a confirmatory results. The results of Anmicrobial sensitivity of the isolated strains revealed that tetracycline (TE30), oxytetracycline (T30), nalidixic acid (NA30), norfloxacin (NOR10) and sulpha-Trimethoprim (SXT25) were the drugs of choice against Aeromonas hydrophila, tetracycline (TE30),oxytetracycline (T30), tobramicin (TOB10) and kanamycin (K30) were the drugs of choice against Pseudomonas flurocence, streptomycin (S10), tobramicin (TOB10), and kanamycin (K30) were the drugs of choice against Pseudomonas putida While oxytetracycline (T30) and nalidixic acid (NA30) were the drugs of choice against Vibrio cholera. The results of Polymerase Chain Reaction (PCR) confirmed the antibiotic sensitivity test results and also confirmed the incidence of Aeromonas hydrophila, Pseudomonas flurocence and Vibrio cholera in the infected fish.

Sources and Toxicological impacts of Surface Water Pollution on Fish in Egypt

Egypt has been listed as one of the most popular countries that are menaced by lack of water by the year 2025 due to overpopulation. The great deposition of highly polluted domestic and industrial effluents into its water ways, made a continuous and prompt damage to its surface and groundwater. The River Nile represents about 97% of Egypt's water resources; however winter rain and nonrenewable groundwater aquifers are also comprised. In Egypt, the main source of pollution is industrial wastes that are poured directly into the main water sources or through the municipal system. On the other hand, the pollution of the Mediterranean coast of Alexandria is mainly due to the discharge of wastes of industrial plants into the sea via Lake Marriott. The rural populations have little or even no access to sewer systems or wastewater treatment facilities and they depend only on the on-site disposal of wastewater. In the Delta region, drainage water is reused for irrigation after mixing with Nile water, while in Upper Egypt drainage water is disposed into the river Nile. Fertilizers and pesticides have been used on a wide range after the constructions of High Dam which resulted in weed flourishing which blocks the waterways, and provides habitats for Bilharzia snails. Egyptian fish aquaria exposed to toxicity due to water pollution from chemical plants and sewage pipes. The main sources of heavy metal pollution of water are industrial and agricultural discharges. Other sources also include: coal and oil combustion, phosphate fertilizers, plastics and pesticides. Recently, the consumption of contaminated fish has been the possible cause of heavy metal poisoning in human. The aim of this review is to disclose the main sources of water pollution in Egypt, and to elucidate the side effects of this pollution on fish.

Pathological and Molecular Characterization of Lymphocystis Disease Virus (LCDV) In Sea Bream Fish in Egypt

Hypertrophied nodules or papilloma like lesions were detected in the skin and fin of Sea bream farms (at Mothalath El Deba and Bardaweil Lake) in Egypt with morbidity rate reached to 70% and mortality rate up to 40%. A total of 20 affected cultured sea bream samples were collected for laboratory examinations. Histopathological examination revealed intracytoplasmic basophilic inclusion bodies in the skin and fins lesions. In addition, a thick hyaline capsule surrounding the hypertrophied fibroblast and contain heavily enlarged cells (lymphocystis) with necrosis and inflammatory response. PCR results with primers specific for the gene encoding major capsid protein (MCP) gave a predicted amplified product at 405 bp fragment by agarose gel electrophoresis. The current results encourage further investigations for this virus in Egyptian farms and recommend the development of prevention strategies against LCDV in Egypt.

MONITORING OF ORGANOCHLORINE PESTICIDE RESIDUES IN OREOCHROMIS NILOTICUS COLLECTED FROM SOME LOCALITIES IN EGYPT

Tilapia nilotica (Oreochomis niloticus) is the major fish species consumed in Egypt, particularly due to its high nutritive value, palatability and relatively low price compared with other kinds of fishes or red meat. In Egypt, tilapia fish is caught directly from river Nile or cultured in a specified aquaculture. Organochlorine pesticides (OCPs) have been extensively used in Egypt and many African countries in the past century for the control of the agricultural pests. A major character of OCPs is their persistent bio-accumulation in the environment, especially in the food chain, where they can get reach to humans. There is few reports had investigated the current scenario of OCPs contamination in fish in Egypt, particularly in Upper Egypt cities such as Sohag. Additionally, fish is consumed cooked in Egypt not raw like many Asian countries. Therefore, this study aimed at monitoring the residue levels of different OCPs in tilapia fish caught from Upper Egypt (Sohag) and compared with either that from northern part of Egypt (Damietta) or with fish cultured in a control location (Abbasa). Additionally, the effect of different cooking methods (boiling, grilling and pan-frying) on the residue levels of OCPs was investigated. The tested OCPs included pp-DDT and its metabolites pp-DDD and pp-DDE; hexachlorohexanes (HCHs) including α HCH and γ HCH; heptachlor and heptachlor epoxide; aldrin and endrin; chlordane, methoxychlor and hexachloride benzene and were detected using electron capture gas chromatography equipped with Ni63 – electron capture detector. The recorded results revealed that tilapia collected from Damietta had the highest incidence of OCPs’ contamination (75%), over than that collected from Sohag (60%) compared to control value (35%). All examined samples had OCPs residues within the maximum permissible limits (MPLs) set by world health organization. Pan-frying had the highest reduction effect on the OCPs’ residues followed by grilling and boiling. The public health significance of the examined OCPs was also discussed.

CONSUMPTION OF FISH IN EGYPT

Food is a vital necessity for humans. Providing food in quantity and quality is not only necessary to meet biological needs or to achieve a decent standard of living, it is also an essential step for civilizational leapfrogging. The results indicate that the total Egyptian fish production increased at a statistically significant annual rate estimated at 57.2 thousand tons per year. The quantity of fish consumption in Egypt increases annually at a statistical average of 62 thousand tons per year. At a statistically significant annual rate of 0.44 kg per year, and the fish gap shows its fluctuation between the rise and fall during the period considered and the most important results of the consumer spending functions of the animal protein group in Egypt and the expenditure elasticities of these groups according to the economic and social factors that the expenditure on the animal protein group is generally higher. The results also showed the effect of both urban and rural on the consumption patterns of the animal protein group. The results indicate that the consumption expenditure patterns on the animal protein group in both rural and urban areas will be affected. In addition, the expenditure on urban animal protein will decrease in general from 2013 to 2015, countryside. The results showed that the household expenditure in Egypt has different and significant differences according to the annual expenditure categories of the private household, income, expenditure and consumption 2012-2013-2015-2016.

Evaluation of electrofishing adopted by Egyptian fish farmers

Upon the demand of a private fish farmer, this study was applied to assess the influence of electro-fishing adopted by some Egyptian fish farmers on the fish welfare and quality. Therefore, a total of 60 Nile tilapia (Oreochromis niloticus) were sampled; from which 30 were stunned by electrofishing and the remainders by conventional fishing. Biochemical analysis (oxidative stress and energy status), meat quality based on total bacterial count (TBC) and pathological alterations were assessed. Biochemical analysis in both liver and muscle tissue showed that electro-stunned fish exhibited low oxidative stress and high energy status. Meat of electro-stunned fish showed an acceptable limit of TBC (Max. limit 107) while the histopathological examination revealed various tissue reactions. These were in the form of congestion in branchial, hepatoportal, brain and splenic blood vessels with edema in brain and pericardium. In addition, there was mild inflammatory reaction together with the presence of eosinophilic granular cells and perivascular melanophores aggregation in both branchial and muscular tissue.As a consequence of this work, we recommend the use of electrofishing method in Egypt after modifying the current tool by reducing applied voltage. Further studies and more optimization are needed to cover both fish farmers and animal welfare issues, and take in consideration the human safety precautions.

ECONOMIC ANALYSIS OF MARKETING AND PRICE CHANGES FOR THE MOST IMPORTANT FISH IN AL-OBOUR MARKET ARAB REPUBLIC OF EGYPT

The relative importance of fish in Egypt increased from 1482 thousand tons in 21001 to 15525 thousand tons in 2014, an increase of 43 thousand tons or about 2%. The fish are characterized by fluctuations in productivity and price, which affects the production and marketing decisions of both the producer and the consumer and lead to the emergence of problems and difficulties in marketing, the most important lack of marketing information and the modest marketing services available on the market and the high share of marketing intermediaries of the consumer price and requires study of the marketing side of the transit market. And used the standards for calculating the marketing margins and the distribution of consumer pounds and the same seasonal analysis of the prices of the most important types of fish during 2010-2014. The research was based on the primary data collected from the market as well as the secondary data obtained from the market management and then the selection of the types of tilapia and crustaceans as the most important types of fish, such as the high market value and demand. The share of the product in the 2014 retail price was about 83% while the wholesaler's share was about 64% while the retailer's share was 11.66% of the retail price. While the share of the wholesaler was 4.6%, while the share of the wholesaler was 19.4%. The efficiency estimate for the marketing costs of the tilapia category according to the variable yield index was 1020%. Therefore, the efficiency can be increased. To 90% which reflects the lack of efficiency and this during 2009 and then increased efficiency to reach a maximum of 100% in 2012-2014. The results of the efficiency assessment of the marketing costs of the cutters according to the variable yield scale of the minimum threshold of 0.5% and thus the efficiency can be increased to 95% which reflect the lack of efficiency and this during 2005 was the best efficiency during the years 2012-2014. The results of the IRS indicate increased marketing costs to improve efficiency during the year 2001-2011 and there was a reduction in costs in 2012 and the efficiency was high. In 2013 and 2014, there was a decrease in the independent variable from decreasing the difference with efficiency stability to reach the same efficiency. For tilapia. The results of the IRS show that the marketing costs to improve efficiency during the period 2001-2011 should be increased for catfish and there was a decrease in costs in 2012 and there was high efficiency. In 2013 and 2014 there was a shortage in the independent variable, Efficiency of access to the same efficiency. On the other hand, the minimum season of wholesale prices of tilapia during the years 2010-2014 in the months (October- November- August) and the maximum during the months (April- May- February), (October- December- November) and the upper limit (April- June- March). The most important marketing problems of fish in the absence of equipment market fish keeping 'weak regulation of the market lack of control on the actual functioning of the auctions market spread of the phenomenon of indiscriminate sale without a license, which requires regulation of dealing in the market and provide the appropriate equipment and provide data and market information for the services of all workers in the market.

Studies on Bacterial Pathogens in Some Marine Fishes in EL-Mansoura, Egypt

A total of 200 marine fish of two different species (100 Tilapia zillii and100 Mugil capito) were randomly collected from different markets, during different seasons. Fish subjected to clinical, postmortem and bacteriological studies. The common clinical signs were darkness of the skin, hemorrhage in the fins base, eyes and different parts of the body, abdominal distention, congestion in gills and increasing in mucous secretion. The Post Mortem findings showed white serous fluid in the abdominal cavity and sometimes tinged with blood and pale or congested liver, kidney and spleen. The bacteriological examination, revealed that the prevalence of bacterial pathogens among naturally infected marine fishes were A. hydrophila (52; 39.39%), V. alginolyticus (38; 28.79%), Ps. fluorescens (24; 18.18%), V. cholerae (10; 7.58%) and Ps. aeruginosa (8; 6.06%). The highest prevalence of bacterial infection was during summer (33.33%) followed by spring (24.42%), then autumn (21.97%), while the least prevalence was in the winter season (20.46%). A. hydrophila was highly pathogenic to T. zillii causing 100% mortality followed by V. alginolyticus causing (90%) mortality, then Ps. fluorescens (80%), Ps. aeruginosa (60%) while V. cholerae was non-pathogenic. The results of antibiogram revealed that ciprofloxacin and nalidixic acid were effective against A. hydrophila, while ciprofloxacin and rifampicin were effective against Ps. fluorescens. Ciprofloxacin and amikacin were effective against Ps. aeruginosa. While V. alginolyticus was highly sensitive to ciprofloxacin. High prevalence of pathogenic and resistant bacterial strains among marine fishes in Egypt, requires strict control measures from the responsible authorities.