NEW TECHNOLOGIES IN AQUACULTURE DEVELOPMENT (JOURNAL OF FISHERIES)
Year:2017 | Volume:10 | Issue:4 |Papers Count:9

Silver carp (Hipophthalmichthys molitrix) is one of the largest members of the family Cyprinidae and is the only member of the genus Ctenopharyngodon. 40 fish were selected with the weight and total length of 8510± 461gr and 767± 32 mm, respectively. In this study, CPE (carp Pituitary extract) and Ova prim were used to induce spawning in Silver carp brooders. Experiment was carried out in 2 treatments (CPE and Ova prim), 20 fish in each treatment (10 male + 10 female). In treatment 1, CPE was used 4 mg/kg for females and3 mg/kg for males. In treatment 2, Ova prim was used 0. 5ml/kg for female and 0. 25 mg/kg for males. Water temperature in Propagation time was 25± 1° C. Ovaprim and CPE injection were carried out in 1 stage. Spawning success was 100% in silver carp broad stock in Ova prim treatment while in CPE treatment was 80% that showed no significant difference (P>0. 05). Latency Period was 13-14 h in both treatments (P>0. 05). Fertilization ratio and survival ratio in Ova prim and CPE treatments was 87± 4. 49%, 84. 5± 1. 06 and 63. 5± 3. 7%, 65. 2± 2. 32 respectively (P<0. 05). In Ova prim treatment, Hatching ratio, working fecundity were 84. 3± 4. 05 and 530819± 33425 thousand eggs, respectively and in CPE treatment was 65. 6± 3. 64% and 406336± 24261 thousand eggs, respectively that was no significant difference(P>0. 05). Working fecundity in Ova prim and CPE was 62353. 6± 707 thousand eggs and 66618± 3. 141 thousand eggs, respectively that was significant difference(P<0. 05). According to results breeding indices in Ova prim injection treatment had higher efficiency in spawning induction compare to CPE treatment.

Curret survey performed to examine the effect of anti fungal extract of Thymus vulgaris and Origanu majorana on Saprolegnia sp. In propogation of Shshid Motahhari in Yasuj province. For this purpose 50 fungal samples from fin, gill surface and skin of rainbow trout were got randomly and cultured on sabouraud dextrose agar medium then was transferred to Veterinary Medicine of Islamic Azad University, Kazerun branch. Cultured samples in ancubator were diagnosed as Saprolegnia sp. by identification key and were cultured on Trypton soy broth once more. Extraction was done by method of suspension in methanol 96%. The effect of antfungal was examined by producing continuous concentration of extracts to determine MIC and MBC. The results showed that the minimum inhibitory concentration (MIC) of Thymus vulgaris extract at concentration of 40 percent, 50 percent, 60 percent, 70 percent and 80 percent, were 16, 16, 8, 4 and 2 mg/ml respectively and the minimum inhibitory concentration (MIC) of the Origanu majorana extract in concentrations of 40 percent, 50 percent, 60 percent, 70 percent and 80 percent, were 16, 8, 8, 4 and 2 mg/ml, respectively. The minimum fungicidal concentration (MFC) of Thymus vulgaris extract at concentration of 60 percent, 70 percent and 80 percent were 16, 4 and 4 mg/ml respectively and the minimum fungicidal concentration (MFC) of Origanu majoranaextract at concentration of 60 percent, 70 percent and 80 percent were 16, 8, 8 mg/ml respectively. According to Two-Way Analysis of Variance there was a significant relationship between extract concentration of herbal drug and their effects )P≥ 0. 05).

At first, microalgae (Scenedesmus sp. ) was collected by plankton net (20 microns), samples were collected from Farahabad area and in Phycolab (This research was performed by Caspian research group of fisheries and water pollutants) and were seperated and purified by Pipette Pasture method. After the medium culture was made, the above green algae with primary culture density (7×106 cells/ml) was inoculated in Phycolab system at temperature 25± 2 degree centigrade and 3500± 350 LUX light density. In this experiment, it was considered with 2 treatments and aeach treatment with 3 replicates. The observation microalga was carried out by light microscope (40X). The tool of counting was utilized by Hemacytometer slide (for five grade samples counting). In addition, the numbers of colonies were separately counted. In 10 days counting, The most average of colonies amount, was 39. 7% four-cells colony in Z8+N+P media and 53. 5% single-cells colony in TMRL media. Generally the comparison of 2 medium cultures was shown that the efficacy of Z8+N+P medium culture was higher than TMRL medium culture for growth of Scenedesmus micro algae in lab circumstance.

The investigation has been done in order to identification and study of some biological characteristics of fishes in Arasbaran reservoir in east Azerbaijan province in summer 2010. For this purpose, 8 stations were selected in reservoir and its only tributary (Selin-Chay) and the fishes were caught with gill-nets (30 to 80 mm), 6 mm mesh size seine and electrofishing gear, too. The results showed that 5 species from Cyprinidae and one from Nemacheilidae families live in the reservoir and its tributary. Cyprinids with 76. 5% of the total caught fish were abundant and they were observed at all stations. Barbus cf. cyri, Hemiculter leucisculus and Oxynoemacheilus cf. bergiana respectively with 39. 5, 24. 1 and 23. 5% in Selin-Chay River and H. leucisculus with 85. 0% in reservoir by beach seine were abundant and Cyprinus carpio was only fish species caught by gill-nets. The averages of total length was 103. 16± 23. 7, 95. 45± 15. 3 and 59. 89± 5. 6 mm in H. leucisculus, Barbus cf. cyri and O. cf. bergiana respectively.

In this study, the physic chemical and phytoplankton population characteristics of natural habitat of fairy shrimps at Khasellou pool in east Azarbaijan were studied. Sampling was carried out at 4 times, April, May, July, 2010 and April, 2011. The results revealed that increasing the phosphate concentration from 0. 35 to 1. 4 mg/L in the water can enhance the phytoplankton population density. The algae flora of this habitat consists of 3 phyla: Chlorophyta, Cyanobacteria and Diatoma containing 10 algae species which Chlorophyta had the most population density in April. The optimum condition for high fairy shrimp metanauplii density were observed at temperature of 16. 4 ° C, dissolved oxygen 9 g/L, pH 6. 3-7. 2, transparency 50 cm and salinity lower than 17 g/L. The results showed that appearance and growth of fairy shrimps in this aquatic habitat was began from early April and their survival was reduced by increasing the temperature, water evaporation and salinity of its culture medium and finally died. Thus, water temperature and salinity can influence on hatching rate of this species.

This study was conducted 1n 2014, and the bloodstock fed from same food (mainly Perinereis nuntica an cattle fish). The maturation and propagation of bloodstock, were done in separated 4 tons fiberglass tanks. In the period of bloodstock propagation, tried that, with the aid of sediment chamber, sandy filter, ultra-filter, ultra violet and antiseptic material, water quality reached to the suitable level. With the notice of importance of water physic-chemical factors on the reproduction of western white shrimp, Daily dissolved oxygen, temperature and pH were measured. The mean temperature, oxygen and pH of water measured 28. 16± 1. 30 0 C, 7. 360± 0. 46 mg/l and 8. 15± 0. 20, respectively. The salinity of water was maintained at 33± 2 PPT. Totally we can noted that, the physico-chemical factors were in the suitable range. Due to the propagation of bloodstock, the Nauplius per each brooder were 25 thousand, the post larvae per each brooder were 6 thousands, the post larvae from Nauplius was 24 percent and the spawning frequency per each brooder was 2. 09 times. In the end of spawning period, 600 thousands PL12 were produced.

In order to evaluate the behavior of Pseudomonas fluorescens and other microbial factors (TVC and PTC) and two chemical parameters( pH and PV) in presence of a natural preservative ethanoic extract and nano-encapsulation of Origanum vulgare after preparation of kilka mince (Clupeonella cultriventris), in two concentration of ethanolic extract of O. vulgare (0. 3 %, 0. 5 %) and nano-encapsulation of O. vulgare (0. 3 %, 0. 5 %) was added to kilka mince infected with P. fluorescens and at refrigerator temperature for 20 days were examined and microbial change of P. fluorescens was evaluated in period times 0, 4, 8, 12, 16 and 20 days. The results showed that the nano-encapsulation of O. vulgare, especially at a 0. 5% concentration was more effective than conventional form that leading to a slower rate of growth of P. fluorescens and aso other microbial and chemical except pH in kilka mince and significant difference was observed between nano-encapsulation of O. vulgare with conventional form (P<0. 05). The general conclusions derived from this study was that although nano-encapsulated form, in concentration of 0. 5%, compared to other concentrations had better results but to achieve the better results and enhanced antimicrobial activity of O. vulgare in kilka mince require to using the higher concentrations of O. vulgare and evaluation thorough of biological and chemical parameters.

Fast development of aquaculture and increasing fish demand lead to intensification of fish culture, magnifying stressors for fish and thus heightening the risk of disease Until now, chemotherapy has been widely used to prevent and treat disease outbreaks, although use of chemical drugs has multiple negative impacts on environment and human health e. g. resistant bacterial strains and residual accumulation in tissue. Hence, disease management in aquaculture should concentrate on environmentally friendly and lasting methods. Recently, increasing attention is being paid to the use of plant products for disease control in aquaculture as an alternative to chemical treatments. Plant products have been reported to stimulate appetite and promote weight gain, to act as immunostimulant and to have antibacterial and anti parasitic properties in fish and shellfish aquaculture due to active molecules such as alkaloids, terpenoids, saponins and flavonoids. However, as it is a relatively emerging practice there is still little knowledge on the long-term effects of plant extracts on fish physiology as well as a lack of homogenization in the extract preparation and fish administration of the plant extracts. This article aims to review the studies carried out on the use of plant products and their biological effects on growth, hematological and immunological parameters of giant sturgeon.