Iranian Scientific Fisheries Journal
Year:2017 | Volume:25 | Issue:4|Papers Count:17

This study was carried out to investigate the effects of different levels of fennel essential oil (Foeniculum vulgare) on some biochemical parameters and salinity stress resistance of Caspian Kutum (Rutilus kutum) fry. For this purpose, Kutum fry with an average initial weight 0.6±0.002 gr were divided randomly in 5 treatments including 0 (control), 100, 200, 400 and 600 mg fennel essential oil/kg diet and fed 3 times a day at a ratio of 7-12% body weight for 60 days. At the end of the experiment, biochemical parameters and salinity stress resistance were assessed. Results of serum biochemical analyze showed that the highest level of total protein and globulin was observed in 600 mg fennel essential oil/kg diet. The highest level of albumin and cholesterol was observed in 100 and 400 mg fennel essential oil/kg diet and the highest level of triglyceride, glucose and cortisol was observed in control (p<0.05). Results of salinity stress (6, 13 and 20 g/l) showed that 100 and 400 mg fennel essential oil/kg diet treatments showed the lowest response to stress and there were the lowest changes in cortisol and glucose levels before and after stress compare to control. Highest survival was observed in 100 and 400 mg fennel essential oil/kg diet. In conclusion results suggested that Fennel essential oil can improve immune system of fries by promoting biochemical parameters (total protein, albumin, globulin, triglyceride, glucose and cortisol). Also plays important role in increasing stress resistance of Kutum fry and the best operation is related to 100 mg fennel essential oil/kg diet.

During the growth of population in the world, Recirculating Aquaculture Systems (RAS) are developing due to more production and less water consumption and many scientists have studied on water quality and solid removal at these systems. In this paper to study on settling pattern of solid particles on a bed of aquaculture cylindrical tanks, a tank in diameter of 2.14 m and height of 0.59 m and inlet flow using three nozzles in 8 mm diameter has implemented. Quality and quantity studies of settling patterns of solid particles in six injection location (by changing the injection location of radial alignment for three options and on the pyramid of tank for others) show that injection location by the middle location of radial length and of third station (there are 6 stations on the pyramid of the tank and each station has located at 60 degrees from the last station) created more uniform sedimentation on the bed. Also, laboratory observations show that the low density materials such as fish feed, which has a high rate of immersion are more disposed to exit due to spiral flow of cylindrical tanks.

In present research, effect of dietary astaxanthin levels in sources of synthetic and algal on vitamins A and E content of egg rainbow trout broodstock was investigated, totally for 120 days. It was considered seven groups consisting six treatments (T1-T6) in two different astaxanthin sources and control (C). According to experiment design, treatments were arranged as algal astaxanthin (Haematococcus pluvialis) in the three levels of 2.67, 3.55 and 8gr/kg food (T1, T2, T3); and synthetic astaxanthin in three levels of 40, 80 and 120mg/kg food (T4, T5, T6). Egg vitamins A and E content in obtained eggs from all treatments during spawning season was measured. The highest (280.88±22.51 ng) and the lowest (147.82±12.71ng) amount of vitamin A were observed in T2 and control group, respectively. The highest (19.71±2.92μg) and the lowest (5.27±0.51μg) amount of vitamin E were obtained in T3 and control group, respectively. By increasing level of astaxanthin in both sources of algal and synthetic, content of vitamin E in egg increased but the effect of algal source on these indices was more perfect. In general present study show that, feeding broodstock affected on quality content of egg, It also concluded that natural astaxanthin (Haematococcus pluvialis) for the reason that contains supplementary nutritious, is extraordinary preferable than synthetic astaxanthin to improve vitamins content of egg in rainbow trout.

Sea cucumber is a valuable resource containing several materials that can be used as natural products and pharmaceutical industries. In this study, proximate composition and the amount of total phenols, flavonoids and antioxidant activity of fresh and rehydrated (after drying) sea cucumber, Holothuria parva, were examined. The samples were collected from Bandar Lengeh in the Persian Gulf during low tide and kept frozen. The samples were freeze-dried and the moisture content was calculated. The protein, lipid, ash and carbohydrate contents were then measured. The amounts of antioxidant activity (DPPH), phenol and flavonoid contents were also measured. All results have possibility (p<0.05). In fresh sample, the moisture, protein, lipid, ash and carbohydrate contents were ±81.20, ± 12.00, ± 0.34, ±5.50 and ±0.95%, respectively, while they were ±92.50, ±3.76, ±0.36, ±1.00 and ±2.07% in rehydrated sample. The antioxidant activity in fresh and rehydrated samples were equal to ±0.063 and ±0.060 mg vitamin C/g dry sample, respectively. The IC50 in fresh sample was ±5.26 while in the rehydrated sample was ±4.14. Total phenol content of fresh and rehydrated samples were equal to ±0.22 and ±0.19 mg gallic acid/g dry sample, repectively. The flavonoid contents in fresh and rehydrated samples were equal to ±3.86 and ±5.02 mg Quercetin/g dry sample, respectively. The amounts of protein and ash in fresh sample were significantly higher than rehydrated sample with significant difference (p<0.05). Moisture in rehydrated sample was significantly higher than fresh sample with significant difference (p<0.05). There were no significant difference between fresh and rehydrated samples in terms of their phenon and flavonoid contents. The DPPH radical scavenging capacity was significantly higher in the fresh sample compared to the rehydrated sample with significant difference (p<0.05). It can be concluded that this species of fresh sea cucumber has more antioxidant activity than rehydrated (after drying) sea cucumber and more beneficial to be used in pharmaceutical and food industries.

The main objectives of the present study were to estimate of biomass during 1997-2014 and maximum sustainable yield of common kilka Clupeonella cultriventris Borodin, 1904 in 2013 in Iranian waters of the Caspian Sea. This paper examines the maximum sustainable yield (MSY) and fishing intensity at MSY (fMSY) and then using fMSY, yield-per-recruit and spawning biomass-per-recruit under various harvest strategies of Fmax, F0.1 and F40%; the acceptable biological catch (ABC) was estimated. During 1997-2014, the biomass of common kilka was increased from 22000 in 1997 to 112000 t in 2009 then declined to 83300 in 2013. In the period, the instantaneous coefficient of fishing mortality varied between 0.246/yr to 1.640/yr and the exploration rates were 0.327 and 0.764. The reference points of common kilka at F0.1 and F40% were estimated 0.92 and 0.80 year−1, respectively. According to Schafer model the MSY and fMSY were estimated 22670 t and 8690 vessel×nights (a unit of effort). During 2013, the ABC of common kilka was estimated 17500, 20060, 23500 and 18900 t in tiers 2, 3, 4 and 5, respectively. However, for the implementation of a precautionary management approach the lower and more accurate ABC-value, based on more information, should be selected and thus the catch should be restricted to 17500 t.

Parasitic infestation of two native fish species in Behesht-Abad River were investigated at spring 2013. In this study 52 Chondrostoma regium and Aphanius vladykovi (26 from each species) were sampled and transferred to the laboratory. Then the weight and total length of fish were measured and investigated their infestation to parasites by microscope and stereomicrpscope. Some of the observed parasites are reported for the first time as new host records of: Philometra sp on the abdominal cavity of C. regium, Moreover, some external and internal parasites identified to the species and genus level including: Ichthyophthirius multifiliis in skin and gill of C. regium and A. vladykovi, one immature digenean; Allocreadium isoporum on the intestine of A. vladykovi and Trichodina sp on gill and skin of C. regium and A. vladykovi. The highest frequency of I. multifiliis (96.15%) was observed in gill of A. vladykovi and the lowest frequency  was related to Tricodina sp in skin of C. regium (23.07%). A. isoporum Infestation was only observed in the intestine of A. vladykovi (mean±SD; 5.42±3.73) and philometra sp infection was only observed in the abdominal cavity of C. regium (mean±SD; 3.25±.82). The maximum average (±SD) infection intensity belonged to I. multifiliis in skin of C. regium (69.9±72.07, range: 12-196).

Nemipterid fishes are considered as one of the commercial fish family having considerable catch amount in the Persian Gulf and Oman Sea. There was an annual monitoring survey during 2003-2013 in the Oman Sea using a research bottom trawler for stock assessment purposes. The whole area was stratified into five strata (or sub region) and four depth layers of 10-20, 20-30, 30-50, 50-100 m. The results showed that the best fishing ground for this family were both in western and eastern study area of the Oman Sea, Sistan-o-Baluchistan Province. Amongst five classified sub regions, the Meidani, Galak, Rabech and Biahi in the western part showing the most density with CPUA value of 293.7 kg/km2. A comparison between different covered depth layers, it was found that the highest CPUA (331.2 kg/km2) belonged to the depths more than 30 m and with decreasing depth there was a descending trend in catch per unit area value with the lowest value for 10-20 m depths (28.6 kg/km2). This 10 years data show the important finding of increasing of density and catch per unit of area of Nemipterid fishes.

Every year, after fishing period, the sturgeon gillnets are assessed base on physical characters by the management of sturgeon fishes in Golestan Province. Net are put aside and replaced by new one if they qualification are not net. In spite of importance of strength ropes, unfortunately, there is a little research in this regards. In addition, previous research are not applied storage conditions and physical damages. Therefore, researcher are determined to do a research in this regards. For this reason some materials from new net, storage net, damaged net, put aside net, etc. collected and tested by an Instron. Then data analyzed by factorial test in complete randomized and variance and average compared in 5% significant level by SPSS version 17. The results shows that there is not significant difference between new net (blank) and new net kept in storage for two years in strength point (p>0.05). However, there is significant difference in breaking point, damaged nets (p<0.05). Regarding the effect of reducing, the net strength during the storage, lack of significant difference between new storage net, represents a quality loss in making of new nets.

This study was performed in order to determine the effect of Oregano (Origanum vulgare) extract on Streptococcus ineae infection in rainbow trout. 360  rainbow trout weighing 15±1 gr were randomly allocated into three treatment groups with three repetition,  including: 1) Control group, 2) Oregano extract treated group (1% of diet), 3) Felorfenicol treated group (10mg/kg fish), all feed one time a day for two weeks. At the end of the second week, 5 fish of each repetition collected and sampled from their blood and tissue of spleen and kidney. After the bleeding, all the samples injected with streptococcus ineae. After two weeks mortality rate calculated and after the bleeding, sampled from the spleen and kidney of the samples. Total cunt analysis conducted on the spleen samples in 4 logarithmic concentrations. in the second phase all the samples primarily injected with S.ineae and then treated with Oregano concentration and Felorfenicol for two weeks. After the two steps of bleeding, in sterile qualifications, the spleen of the fishes sampled for total cunt analysis. Blood cells counting and lisosym activity indicated in all blood samples. The results shown that total mortality in both of the phases of experiment in Oregano extract (OE) treatment was significantly lower comparing to control group (p<0.05). Furthermore the results of blood cells counting shown that WBC and monocyts percents were significantly higher in Oe and Felorfenicol treatment groups (p<0.05). This phenomenon was because of the effects of Oe and Felorfenicol. Nevertheless the lysozym activity degreased comparing to control group (p<0.05). But total count analysis shown that bacterial audience in spleen degreased treating by Oe and felorfenicol. It was concluded that supplementation of Oe registered lower mortality and bacterial audience, and better hematological parameters in fishes, compared with control group. Therefore supplementation of Oe in fish diet would be effective in prevention and treatment of S.iniae in rainbow trout.

This study was aimed to investigate the effects of pomegranate (Punica granatum) seed kernel meal (pskm) as a supplement in the diet of rainbow trout (Oncorhynchus mykiss), The experiment was carried out  in growth in a period of 90 days since the 12.11.2014 until the 12.03.2015 in Abzi Eksir Koesar complex , situated in south east of Tehran. 600 fingerlings with average weight of 6.74 gram and average length of 5.50 centimeter were divided to five treatments, The control group was without any pskm, and the other groups with added 1, 2, 3 and 4 percent pskm Respectively. For greater certainty each treatments had three replicates. Result indicated that pskm caused highest increased growth parameters in treatment 3 with 3 percent pskm, with other treatments and groups. growth parameters including weight with maximum of 47.74 gram , length were 15.03 centimeter ,weight gain with maximum of 41.15 gram, length increase with the maximum of 9.71 centimeter, Weight gain percentage with maximum amount of 572.1, specific growth rate with 0.45 and specific length rate with 0.1 mm. All growth parameters with the best value was seen in treatments 3.This result is due to the presence of high levels of appetite stimulants such as polyphenols of pskm (p<0.05). Result also indicated that the level of pskm in treatment 4, did not cause enough different with the control group, mainly because of higher amount of tannin in their diet.