نشریه آبزیان زینتی
سال هفتم شماره 1 (بهار 1399)

Over the past two decades, Studies have been done on the inland water resources of Sistan and Baluchistan province, which was one of the areas studied in the first phase of the Biodiversity Project, approved by the Fisheries Research Institute. Sampling was performed on river with using electroshocker and Salic. After fishing, the specimens were fix by formalin and biometric measured in the Morphology Laboratory, based on morphometric and meristic characteristics. The results of this study showed that 9 fish species belonging to 5 family Comprising of Cyprinidae ,Cyprinodontidae, Poeciliidae, Chaniidae and Nemacheilidae have been identified. This species were found in the Province and they can be used as Ornamental fish.

Today, the role of aquaculture in food production, economic development and food security is well known, but this industry still faces many challenges, including the prevalence of pathogens in farming systems. So far, various chemical, physical and biological methods have been used to control and prevent the spread of pathogens in farming environments, some of which are unfortunately not widely used. In recent years, significant advances in nanotechnology have led to the introduction of this knowledge into various industries, including aquaculture. So far, considerable studies have been done on the application of silver nanoparticles (AgNPs) in the aquaculture industry. In addition, there is evidence that these substances play an important role in controlling and preventing the spread of pathogens in aquatic environments. In this regard, the present study aims to investigate the antimicrobial effects of silver nanoparticles in order to control aquatic diseases in farming systems. In addition, the challenges and risks of using these substances in farming environments are also briefly examined. A review of available sources and databases has shown that most studies have looked at the effects of silver nanoparticles on bacterial agents. Also, the findings showed that silver nanoparticles can be used by farmers for sustainable management and improvement of health conditions in aquaculture systems. Of course, it should be noted that the use of these substances should be done with the utmost caution and observance of health and environmental aspects.

investigation, the efficacy of two anesthetic agents Cuminum cyminum essential oils (EOs) and 2- in different dosages were compared in zebrafish, Danio Fish (1.3 ± 0.2 g) were anesthetized with different concentration of C. (0.12, 0.16, 0.20, 0.24, 0.32 and 0.40 ml/l) and 2- (0.35, 0.40, 0.45, 0.50, 0.55 and 0.60 ml/l) by After that, the anesthesia was induced and the biometric measurements were completed, fish were transferred to anesthetic-free aquaria to allow for recovery. The lowest effective concentrations based on the efficacy criteria of complete anesthesia induction within 180s and recovery within 300s were determined to be 0.24 ml/l (induction: 157.6±55.3s and recovery time: 133.3±14.2s) for C. and 0.35 ml/l (induction: 126.6±23.6s and recovery time: 124.6±31.5s) for 2-. An inverse exponential relationship was observed between concentrations of anesthetics (C. and 2-) and induction time. This study shows the high potential of C. for fish anesthesia, and the C. different concentrations (0.24-0.40 ml/l) seem to be suitable for anesthetization of

Growth in animals is controlled by genetic, environmental, and nutritional factors, including external factors (temperature, pressure, salinity, and light) in the evolution of cold-blooded animals. In this study, the effects of three different light treatments on the growth and survival rates of guppy larvae (Poecilia reticulata) were investigated. The larvae of this species with an average initial weight of 0.015 g for a month were exposed to 12 h light and 12 h dark (12 L:12 D) as control treatment, 24 h light without darkness (24 L:0D) and 24 h dark without light (0 L:24 D). At the end of the experiment, the larvae affected by the 24 h light treatment had the highest growth, body weight gain and specific growth rate, which showed a significant difference with the 24 h dark treatment (P<0.05) however, the effects of the photoperiod treatments on larval survival were not significant (P<0.05). The results of this study showed that the photoperiod is one of the factors influencing the growth rate of this species and with increasing the photoperiod the growth will be better.

Injection of gonadotropin-releasing hormone analogues (GnRHs) produces luteinizing hormone (LH) from pituitary that stimulates gonadal maturation. In female fish, these analogues drive the final oocyte maturation, ovulation and finally spawning. Traditionally, they have been injected either intramuscularly or intraperitoneally. Depending on GnRH type, fish species and water temperature, one-step administration causes the peak of LH within 12-72 hours. In some fishes, this short-time effect of injection is enough for spawning during 2-3 days following the injection. However, asynchronous fishes need more injections but, multiple hormone injections are stressful and harmful and in the long-term, they inhibit reproduction. Therefore, sustained-release delivery systems can be used. A single application of GnRHa-delivery system enters GnRHa into the blood stream continuously, resulting pituitary stimulation for releasing LH that may take several weeks. Therefore, in delivery system, multiple injections can be replaced by single injection. There are different delivery systems includes: cholesterol pellets, ethylene-vinyl acetate implants, and biodegradable microspheres. This paper discusses the methods of hormonal implantation and possibility of its application in some Iranian fishes.

In order to identify and determine the distribution of economic and ornamental seashells in the northern coasts of the Persian Gulf, sampling was done in upper, middle and bottom intertidal zone in all four seasons and in mud, sand and rocky substrates. Onshore samples were collected through diving and trawling. Identification of specimens was carried out inside the country and confirmed by Institute of Malacology, Tokyo, Japan.381 species belonging to 117 families and 231 genera were identified. There was no significant difference in the warm and cold months in terms of diversity, although the density of the species was much higher in the warm seasons. In terms of species diversity, Bandar-length, Faroor and Hendurabi islands were the most diverse. In terms of size, the largest shells found were Sepia pharaonius and Pinna muricata with a total length of 45 cm and the smallest one with a size of 1 mm was Acteocina involute.