جستجوی مقالات مرتبط با کلیدواژه « ماهی » در نشریات گروه « زیست شناسی »

The aquaculture industry has caused direct and indirect contact between humans and target species, including fish. Human contact with different aquatic species can cause the spread of common diseases between humans and aquatic animals and their transmission, which is very dangerous for workers and breeders of aquatic organisms. Therefore, maintaining the biological safety of workers and those who deal with aquaculture centers is recognized as one of the important necessities in this profession. Considering that bacterial agents are one of the most common pathogenic groups in aquatic environments, some important bacterial agents in aquaculture systems that can be the basis for transmitting of common diseases between humans and aquatic animals have been discussed. In this research 4 important groups of bacterial agents common between humans and aquatic animals including Mycobacteria, Streptococcus, Erysipelotrichaceae and Vibrionaceae were investigated. The results showed that the Vibrionaceae group was more prevalent than others. The information presented in the present study can be used to raise awareness and maintain the biological safety of workers and aquaculture farmers who are directly or indirectly related to aquaculture centers. Also, this research recommends the proper implementation of health and biosecurity management protocols to maintain the health of workers in aquaculture centers.

Today, consumption of seafood has a special place among consumers. Consumption of seafood can lead to the transmission of bacterial pathogens of primary or secondary origin, among the most important of these bacteria are Vibrio species that are naturally found in aquatic environments and in the bodies of aquatic organisms. Every year, many cases of food poisoning caused by Vibrio species are reported in consumed fish. The purpose of this research is to investigate the level of Vibrio contamination of raw fish sold in Shahrekord city. In this research, 50 fish samples were prepared from 30 fish and aquatic supply stores in Shahrekord city and then analyzed at the Nutrition and Organic Products Research Center of Islamic Azad University, Shahrekord branch. Vibrio parahaemolyticus, Vibrio cholerae, Vibrio vulnificus, Vibrio mimicus and Vibrio alginolyticus can be mentioned among the most important species investigated. Then, based on the presence or absence of grown spores, 40% of the meat of the studied samples (20 pieces) were infected with Vibrio. The high abundance of Vibrio species in the samples confirms the lack of hygiene in the fish and its products preparation and distribution centers. It seems that the processing stations and the method of transporting and distributing fish do not have proper hygiene.

The Persian Gulf and the Oman Sea are habitats for a variety of aquatic species, especially fish. Heavy metals are crucial pollutants in aquatic ecosystems and can be among the major factors influencing the health of consumers. The purpose of this essay is to conduct a systematic review of studies that have assessed the concentration of heavy metals in the muscle tissue of certain fish species in these waters, spanning from the year 2006 to 2018. This meta-analysis study was performed on 1182 muscle tissues of Pampus argenteus, Platycephalus indicus, Lutjanus johnii, javelin grunter, Johnius belangerii, Otolithes ruber, Scomberomorus commerson, Scomberomorus guttatus, Epinephelus coioides, caught from the Persian Gulf and the Oman Sea, in order to investigate the amount of these metals. Also, the safety of food intake and the comparison with the standards were investigated. The THQ and HI indices were found to be less than 1 in the all species of fish for adults, but for children only in Scomberomorus commerson in HI index is more than one. The amount of mercury, zinc and lead in the all pecies of fish, cadmium in Lutjanus johnii and javelin grunter and nickel in Scomberomorus guttatus and Epinephelus coioides were lower than all standards. The daily and weekly absorption rates for all studied metals were lower than the authorized JECFA Committee due to fish consumption. Also, the lowest amount of allowance for studied metals was found mercury in Scomberomorus commerson, lead in Johnius belangerii and cadmium in Platycephalus indicus. It seems that high use of the Platycephalus indicus in terms of the studied metals has led to health risks in children. Therefore, environmental protection, which it has been influential in creating nutritional health problems, is considered a necessity.

Wound healing is a complex programmed sequence of cellular and molecular processes. The objective of the present study was to evaluate the ability of earthworm’s hydro-alcoholic body extract (EBE) to heal the experimental skin wound in goldfish (Carassius auratus gibelio).

Fish (independent triplicate, 14/group), for 14 days, were divided into 5 groups 1) negative control (Unwounded); 2) pseudo-control (sham): wound treated with EBE carrier (mixture of castor oil and white vaseline); 3) Positive control: wound treated with sodium phenytoin 1%; 4) 1 mg/gr EBE-treated wound, 5) 10 mg/gr EBE-treated wound. In this study, macroscopic and microscopic evaluations and collagen turnover (Hydroxyproline content) in the skin, along with determination of lysozyme activity in blood sera were carried out.

In fish in group 4 (1 mg/gr EBE-treated wound), an increase in the epithelium diameter, good presence and appropriate synthesis of collagen with and low edema in dermis; increased hydroxyproline content; and elevated blood lysozyme activity were observed comparing to other groups.

Our results revealed that application of 1 mg/gr EBE might be as an effective medicinal material in the process of animal wound healing particularly in aquatics.

Natural antioxidants have received much attention due to consumer health and food safety. These antioxidants are found in fruits, plants and bioactive peptides. This paper is going to study the extracts hydrolyzed protein of rainbow trout (Oncorhynchus mykiss) using alkalase and flavorzime enzymes and investigates its antioxidant properties. The antioxidant activity of the hydrolyzed protein was calculated using DPPH free radical scavenging assay and iron ion reduction assay. The results showed that the protein hydrolyzed by alkalase and flavorzime had antioxidant activity and the flavorzime enzyme was able to produce higher protein hydrolysis than the alkalase enzyme. The DPPH radical scavenging ability of the protein hydrolyzed by alkalase was significantly higher than flavorzime (p<0.05). The study of iron reduction power showed that the protein hydrolyzed with flavorzimm had higher reduction power than alkalase (p <0.05). Therefore, the hydrolyzed proteins (less than 3KD) prepared from skin Rainbow trout can be considered as a natural antioxidant.

The high application of the nanoparticles in industry, health and agriculture increases the possibility of nanoparticles entering the environment, especially the aquatic environment. In the present study, the effects of nano colloidal silver and copper oxide nanoparticles (Cu2ONPs) were investigated on the liver and blood plasma of the Caspian kutum (Rutilus kutum) fry by measuring the activity of the ALT, AST, ALP and LDH enzymes. The samples (17.1±3.6 g) were prepared from the Propagation and Reconstruction Center of Dr. Yousoufpour. After exposing the fish to different concentrations of the nano colloidal silver and Cu2ONPs, the blood was collected on the 7th and 21st days of the experiment. At the same time, the liver tissue of the fish was removed and stored in the -70oC until analyzes of the parameters. The results showed changes in the activity of the enzymes in the liver and plasma of the Caspian kutum fry. The most changes of enzymes were observed in the plasma on the 7th day of the experiment. The LDH enzyme had the most changes in the plasma other than the enzymes. On the 21st day, only the plasma LDH had a significant variation. In the liver, the levels of ALT, AST, ALP and LDH enzymes were almost increased during exposure to the nanoparticles. In the liver, as with plasma, the most changes of the enzymes belonged to the LDH. In conclusion, fluctuations in the metabolic enzymes indicate a change in the physiological state of fish under nanoparticles stress that can threaten aquatic health.

The Caspian rivers has importance roles in spawing sites of fishes and regeneration of anadromous fishes in natural proliferation. Lavandvil, Chelvand, Lemir, Hevigh and Chowbar rivers are located in west of Guilan province. These rivers are important for having the special fish population, spawning of migratory fishes and feeding of estuary fishes. Main purposes of this paper is to the role of these rivers in restoring of Caspian Sea anadromous fish species. So diversity and abundance of fishes has been studied in these riveres. Sampling has been done in 5 stations of studied rivers with electrofishing and small-meshed beach seine gears in 2007. Results showed 25 fish species belong to 10 families exist in the rivers and Cyprinidae with 12 species and 82.6% of total populations was dominant. 19 fish species were native or endemic and 6 species alein, too. The study showed 5 species belong to anadromous fishes: Alburnus chalcoides, Cyprinus carpio, Leuciscus aspius, Rutilus kutum and Vimba persa,and they migrate from sea into these rivers for spawning, and the abundance of A. chalcoides and R. kutum was realtively good but the others, few. Thus, it is essential to have an extensional programm for protecting rivers with popular corporation in responsible fishery management system, for conservation and long sustainable exploitation of valuable and commercial fish sepecies.