JOURNAL OF AQUACULTURE SCIENCES
Year:2020 | Volume:8 | Issue:14|Papers Count:18

Considering the agricultural activities near the fish farm and water bodies, intoxication of fish is likely; thus, the aim of this study was to evaluate the effect of flonicamid intoxication on blood ions concentration and gill and kidney damage in common carp. To this, after 96 h-LC50 determination, the fish were exposed to 10% of LC50 concentration (4. 3 mg / l) and after 21 days of exposure, the blood, gill and kidney were taken. The results showed that flonicamid intoxication decreased chlorine and increased potassium concentrations in fish blood, but had no effect on sodium and calcium levels. In addition, the flonicamid exposure was caused numerous damages to the gills and kidney. In the gill, the secondary lamellar edema, secondary lamellar fusion and primary lamellar hyperplasia were observed in the gill. Also, the exudate and melanomacrophage accumulation and degeneration of renal tubules were observed in kidney of the pesticide-exposed fish. The results showed that flonicamid has serious effects on the gill and kidney tissues of carp. These injuries are responsible for some of the ionic changes in fish blood. Therefore, it is recommended that this pesticide is used in farms, care should be taken to prevent the pesticide from entering the water resources in order not to threaten fish health.

The immune system improvement of fishes, especially in valuable species such as the Caspian brown trout (Salmo caspius), is one of the main needs of fish culturists. Therefore, the selection of appropriate immune stimuli that do not adversely affect fish growth while promoting immunity is one of the most important approaches of researchers. In order to investigate the effect of levamisole on the Caspian brown trout, 240 cultivated juvenile with mean weight of 12. 46± 0. 15 g, were fed a diet containing levamisole at concentrations of 300, 600 and 1200 mg/kg diet for 60 days. The control group was fed with a diet without levamisole. At the end of the experiment, in addition to biometry of fish, blood samples were taken for comparison of cellular, biochemical and immunological parameters. The results showed that levamisole had a positive effect on the growth of the Caspian brown trout. In fact, all three concentrations improved the growth performance of fish and the highest percentages of weight gain and specific growth rate were obtained in 1200 mg/kg levamisole. As the amount of levamisole increased, the feed conversion ratio decreased significantly and the protein efficiency ratio increased significantly (P<0. 05). The highest number of white and red blood cells and the highest amount of hemoglobin were observed in 1200 mg/kg levamisole. However, the differences amongst treatments were not significant in term of hematocrit (P>0. 05). There was no significant difference in total protein, albumin, aspartate aminotransferase and alanine aminotransferase activities between different groups. Maximum lysozyme enzyme activity and the highest IgM amount were measured in 1200 mg/kg levamisole. The highest C3 and C4 complement amounts were observed in 600 and 1200 mg/kg levamisole without any significant difference (P>0. 05). Therefore, the addition of levamisole as a dietary supplement to the Caspian brown trout diet to 1200 mg/kg can be suggested to improve the growth and immunity of the Caspian brown trout.

This study was designed to determine the effect of rainbow trout cage culture on the chlorophyll-a content and trophic index value in the Abbas Abad area, southern Caspian Sea. For this purpose, water samples were collected by a distances of 5, 50, 100 and 1000 m from the cages during December 2014 (before rearing period), March and April (during rearing) and August 2015 (post rearing period). In this study, a totalof 42 species of phytoplankton belonging to five phyla (with the dominance of Bacillariophyta) were identified. Chlorophyll-a content varied significantly in different periods and stations (P<0. 05). The highest and lowest chlorophyll-a content was recorded in March and station 5 m (2. 13 μ g/l) and May and station 1000 m (0. 44 μ g / l) away from cages, respectively. The Trophy State Index (TSI) was significantly different between the sampling periods (P<0. 05). The highest TSI (42. 18) was observed in March and then in August (40. 47) and this differences were significant between different periods (P<0. 05), whereas, it was not affected by the distance from the cages (P<0. 05). It seems that the rainbow trout cage culture in the Abbas Abad region no remarkable effect on Chlorophyll-a and trophic index in the vicinity of fish cages due to the small scale and short duration of cage culture activity and strong water currents, so that observed changes were more associated with seasonal fluctuant.

The objective of this study was to evaluate the effects of supplementing organic acid salt on the growth performance, body composition and digestive enzymes activity of yellowfin seabream (Acanthopagrus latus) fingerling fed diets, including low fish meal. Fish with an initial mean weight of 6. 5± 0. 2 g were divided into a control and two treatments, with 10 fish in each replicate, and fed the following supplemented diets for 8 weeks: Control diet, 5 g/kg diet sodium citrate (SC5) and 10 g/kg diet sodium citrate (SC10). At the end of the experiment, the growth performance indices, including mean final weight, weight gain and specific growth rate of fingerlings fed diets containing sodium citrate were significantly higher than control (P<0. 05). The crude protein and crude fat of fish in the group fed diet containing 5 g/kg of sodium citrate was slightly higher than other groups, however, that these differences were not significant (P>0. 05). The specific activity of total protease in fish fed diets containing sodium citrate (5 and 10 g / kg diet) was significantly higher than that of the control group (P<0. 05). The activity of lipase and amylase enzymes was also increasing by rising sodium citrate, but this increase was not significant (P>0. 05). These results indicated that 5 g/kg diet sodium citrate improved growth, enhanced digestive enzymes activity capacities of A. latus fingerling, and may be a potential feed additive for this fish

In this study, optimum conditions for the antioxidant compounds extraction from Sargassum angustifolium algae were determined by response surface methodology. Optimal design with three independent variables: ethanol concentration (with five levels of 0, 25, 50, 75 and 100), extraction time (with three levels of 2, 4 and 6 hours) and solid-liquid ratio (with three levels of 1: 5, 1: 10 and 1: 15) was generated. Total phenolic content (TPC), free radical inhibitory activity (DPPH) and total antioxidant capacity (TAC) were used as responses. The results showed that the maximum TPC in optimal conditions was obtained in distilled water, 6 hours and a 1: 15 solid-liquid ratio, free radical inhibitory activity in ethanol 25%, 4 hours duration, and a solid-liquid ratio of 1: 5 and total antioxidant capacity in ethanol 50%, duration 4 hours and solid-liquid ratio 1: 15. In terms of the above mentioned conditions, the highest amount of TPC was 698. 01 mg gallic acid per gram of dried algae powder, TAC value was 76. 1 mg ascorbic acid per gram of dried algae powder and DPPH value was 86. 02 (RSA%). The results showed that the extract of S. angustifolium could be used as a natural antioxidant in the food industry, as well as food supplementation against oxidative damage.

This study was conducted to optimize the marine microalgae Isochrysis sp. biomass by minimum economic cost using agriculture fertilizers. Fot this purpose, microalgae Isochrysis sp. was cultured under batch culture condition using agriculture fertilizers to evaluate the differences in growth rate (biomass production) with those of analytical grade for 20 days. Four different culture media were prepared based on 100, 75, 50 and 25% cooper formula using commercial agriculture fertilizers and analytical grade inorganic salts and compared with F/2 medium as commonly used media for microalgae cultivation in laboratory scale. Isochrysis sp. showed better results in F/2 medium in terms of growth and intensity, however, no significant difference was found compared to medium 75% (P>0. 05). This treatment i. e. medium 75% cooper for marine microalgae Isochrysis sp. is economically and biomass production have better conditions compared to other treatments. This treatment in addition to the marine microalgae copared to F/2, its cost is about 16 times lower (without consideration of the vitamins analytical grade vitamins). The results revealed that new formulation of fertilizer using commercial agricultural fertilizers as medium is feasible without any negative effect the Isochrysis sp. growth, and can be used as replacedment for the marine microalgae Isochrysis sp. biomass by minimum economic cost using agriculture fertilizers. Fot this purpose, microalgae Isochrysis sp. culture.

Digestarom® P. E. P. MGE contains a standardized mixture of phytogenic essential oils. The aim of this study was to investigate the effect of Digestarom dietary supplement on liver enzymes as well as antioxidant properties of this supplement on common carp. In this study, the effect of dietary Digestarom supplement was investigated in three groups, including a control one without Digestarom, the second group containing 200 mg/kg of Digestarom, and the third group with 400 mg/kg of Digestarom on 225 common carps with a mean weight of 16. 15 ± 2. 98 g for 60 days. After the experiment, sampling of fish was carried out on day 60. Then the growth performance, activity of blood plasma oxidative and liver enzymes was studied. Based on the results, administration of Digestarom has led to improve in growth parameters especially at the level of 200 mg/kg. The results of the experiment did not show significant difference in the level of superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) and malondialdehyde (MDA) between the treatments and the control group (P<0. 05). Comparison of liver enzymes levels such as AST, ALT, ALP and LDH between the treatments and control group showed that despite of changes in the level of these enzymes between the groups, only the ALP significantly increased in the group 2 compared to group 3 and control group (P<0. 05). Based on the results, suplemnting Digestarom in above-mentioned levels probably has a positive effect on growth performances without any negative effect on the liver and antioxidant enzymes in common carp fingerlings.

This research aimed to study the phytoplankton communities and their diversity in warmwater fish culture ponds, and their relationship with the physico-chemical factors of water, in three ponds of Dezful Region during an eight-month period. Based on the results, Chlorophyceae with 17 species (80. 84%) was the most frequently found phytoplankton in pond A2. Pediastrum sp. had the maximum abundance identified species (9879. 18± 382. 21 ind. /L). The highest abundance was found during late June to late July and the minimum one during late February to late March. In pond A12, the Chlorophyceae with 11 species and 69. 92% of the population was the most frequent phytoplankton and Pediastrum sp. was most frequent species. In this pond, the maximum number of phytoplankton was the recorded during the late May to late June and the minimum one during late September to late October. In pond D7, the greatest abundance was recored during late May to late June and the less one during late March to late April. The Chlorophyceae with 14 species and 11. 89% of the population was the most frequent one and Pediastrum simplex was the most frequent species. The highest observed densitie was 76661514 individual per liter in pond A12 (from late May to late June), 26948994 per liter in pond A2 (from late Aril to late May), and 12302943 per liter in pond D7 (from late May to late June). No relationships were found between phytoplankton population and the measured water physicochemical parameters of water.

The Caspian bighead goby (Ponticola gorlap), a member of the family Gobiidae, is found on the southern Caspian Sea basin. Since little information is available about the skeletal structure of this species, therefore, this study was conducted to describe its detailed skeletal structure in the southern Caspian Sea. For this purpose, a total of 17 specimens were collected from Sefid River by electrofishing device. After anesthesia, they were fixed into 10% buffered formalin, and for osteological examination, they were cleared and stained and, their bony characteristics were described in detail. The results showed that Iranian populations of this species can be identified by having traits, including sharp point of the lateral ethomoid, lack of the nasal, separation of the horizontal part from the vertical part of the premaxilary, presence of an ascending process in the dentary and separation of the symplectis and metapterygoid.

The length-weight and some length-length relationships of six fish species, including Lutjanus malabaricus, Acanthopagrus latus, L. johnii, Rastrelliger kanagurta, Gerres longirostris and Sillago sihama from the Persian Gulf were studied. The specimens were collected from landing centers and their morphometics, including total length (TL), fork length (FL), standard length (SL), body depth (BD), and caudal fin height (FH) measured to the nearest mm and weighed to the nearest 0. 1 g. All length-weight relationships were significant, with the coefficient of determination (r2) ranging from 0. 84 (G. longirostris) to 0. 98 (L. malabaricus) (P<0. 01). The parameter b ranged from 2. 54 (R. Kanagurta) to 2. 98 (S. sihama). The results indicated isometric growth in L. malabaricus, A. latus, L. johnii, and S. sihama and negative allometric growth pattern in G. longirostris and R. kanagurta. The results indicated that the length-length (TL-FL and TL-SL) relationships were highly correlated and significant for all species (P<0. 01). The relationship between TL-BD and BD-FH was also significant, except for R. kanagurta (P>0. 01).

Aquaculture is a production activity whose uncontrolled development would cause negative effects on water resources. This study was conducted on Haraz River to investe the sewage impacts of Oncorhynchus mykiss farms and assess the self-purification capability of the river. Sampling was carried out in 3 pilot farms and 12 selected stations containing pre-farm (control) and post-farms stations in distances of 100, 1000 and 2000 meters downstream from the sewage entry point by random method. Due to the self-purification, the impacts of upstream farms did not reach the next and lower-stream ones. Analyzes of physicochemical factors of water including: Temperature, DO, pH, EC, BOD, COD, TDS, TOC, NO3, PO4 were performed. Saproby classification was done based on biological value index. According to the results, in all downstream stations, a significant increase in concentrations of pollutants was obsereved compared to the control station. BOD was signifantly higher in the post-farm stations too. Despite the proper self-purification of river based on zonation, most sections were completely in eutrophic and polysaprob conditions due to the volume of sewage imported. The first studied farm from upstream, imported more pollution to the river and and the second and third farms are in the next ranks. Accoding to Z index, the best water quality belonged to control station of the first farm and the worst, was about the third station of the mentioned farm. Self-purification assessment demonstrated the reliable distance at 2000 m for complete purification. Despite the suitable self-purification of the Haraz river, the effluents from other smaller farms at non-standard distances, has increased the eutrophy of this river. Failure to monitor fish farms, may cause more problems in the future and the river may be in the state of dystrophy.

The aim of this study was to assess the leaf aqueous extract composition of green tea (GT) (Camellia sinensis) on growth performance, feed efficiency, hepatosomatic index (HSI), gonadosomatic index (GSI), and viscerosomatic index (VSI) in convict cichlid (Amatitlania nigrofasciata). For this purpose, fish (initial mean weight, 1. 28± 0. 02 g) were divided into five groups: GT0 (0 mg green tea extract kg-1 of feed), GT50 (50 mg green tea extract kg-1 of feed), GT100 (100 mg green tea extract kg-1 of feed), GT200 (200 mg green tea extract kg-1 of feed), and GT400 (400 mg green tea extract kg-1 of feed). Each treatment had triplicate groups and, in each replicate, there were 15 fish fed to satiety for 84 days. Fish weight and length were measured every 21 days and at the end of trial growth parameters, including specific growth rate (SGR), weight gain (WG), condition factor, daily growth rate (ADG), and nutritional factors including food intake (FI), feed conversion ratio (FCR), as well as HSI, GSI and VSI were measured. The results showed that in GT100 treatment, SGR (1. 97± 0. 04 %/day), WG (5. 53± 0. 07 g) and ADG (0. 98± 0. 01 g/day) was greater than the other groups (P<0. 05). Moreover, the greatest and lowest FI were observed in GT100 (5. 64± 0. 07 g) and GT200 (4. 91± 0. 09 g), respectivly (P<0. 05). Also, the best FCR was observed in GT100 treatment (P<0. 05), but there was no significant difference in HSI, GSI and VSI among trial groups (P>0. 05). The results of this study showed that the use of 100 mg/kg of green tea extract in convict cichlid feed can improve growth performance and nutritional indices.

In this study, Surimi nutritional quality of common Kilka (Clupeonella caspia) prepared by washing and pH shifting methods during freezing storage was investigated. The samples were stored under freezing conditions for three months and their nutritional qualities were evaluated for some nutritional properties (n3/n6 ratio, lipid quality indices such as TI index and AI index and EAA/NEAA ratio). According to the results, changes in AI index in time unit were significant (P<0. 05). The average of the pH shifting during the maintenance period was higher than that of the washing method. Also, the tropogenic index was significantly higher in the pH shifting method than the washing method, and the index decreased in the first two months and increased in the last month of storage. The EAA/NEAA ratio was higher than the wash method in the pH shifting method (P<0. 05). Regarding the changes in the n-3/n-6 ratio, there was no significant difference between the washing method and the pH shifting (P<0. 05), but this ratio had significant changes during the maintenance period and had a significant effect on this index (P<0. 05). The results showed that the values related to nutritional quality indices measured in surimi produced by the pH shifting method have a better utility than the washing method.

The aim of this study was to investigate Trichoptera (arthropod) fauna in the Jajroud River. For this purpose, Trichoptera were collected from three stations (Hajiabad, Saeedabad and Khojir) in Jajroud River and were identified in terms of morphology and taxonomy using identification keys to the level of genus and species. Based on the results, four species of Macrostemum hestia, M. fenesrtratum, M. dohrni and Hydropsyche dolosa from the family Hydropsychidae were identified, which is the first reported in Iran and this river. The frequency of Trichopters in the study areas was very low in the winter months and was highest in June, July and August and then decreased.

The used Caspian roach broodstocks for semi-natural propagations are collected from the Gorgan river estuary during February-March every year and transported to the fisheries center of the stock enhancement and conservation of genetic stocks of Caspian bony fishes. Sampling of Caspian roach broodkstcoks for this study perforemed for 5 successiv years duing 2014 to 2018. Total length and weight of the broodstocks ranged from 21 to 32. 5 cm and from 45. 60 to 423. 50 g, respectively. The largest mean value of lengths and weights were observed in February-March 2014, and the smallest in February-March 2018. Age of broodstocks ranged between 3+ and 9+. Abundance of ages and sexes were different between years. Feamles had positive allometry in all years, while that of males ranged 2. 65 and 3. 05 indicating mainly negative allometric pattern. Different instanteneus growth rates were observed during five years, indicating presence of strong and/or weak ages and/or cohorts in the studied populations. Condition factor of the females were larger than that of males in all periods. The results showed that L-infinity of males ranged from 26. 49 to 38. 53 cm, and that of females from 32. 45 to 41. 97 cm, k-coefficient ranged between 0. 12 and 0. 24 (year-1) for males and between 0. 11 to 0. 21 (year-1) for females, and t0 of males ranged from-0. 21 to-0. 34 (year), and that of females from-0. 39 to-0. 99 (year).

In recent years, common carp cultivation has been proposed for cage culture in the Caspian Sea during the warm seasons, but there is no data available on the effects of water salinity on the physiology of this fish, especially at low weights. Therefore, the present study aimed to investigate the effects of different salinity of water on hematological parameters, including red blood cell count (RBC), hemoglobin concentration (Hb), hematocrit percentage (Hct), mean corpuscular hemoglobin (MCH), mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), white blood cell count (WBC), and and differential count of white blood cell in this fish with an average weight of 5. 53± 0. 57 g were designed. In this experiment, four treatments, including 5, 13, 20 and 30 ppt and fresh water (as a control) were considered for 8 weeks. The results showed that with increasing water salinity, the amount of all studied hematological factors changes significantly (P<0. 05). However, changes in the hemoglobin in different treatments were not statistically significant (P>0. 05). The results of differential white blood cell count showed a significant increase in neutrophils and monocytes due increasing water salinity (P<0. 05).

Hybridization is an important breeding method for obtaining new varieties that increase genetic diversity. Inter-specific hybrids have been produced for aquaculture and stocking programs to increase growth rate, transfer desirable traits between species, combine desirable traits of two parents into a single group. The aim of hybridization in the aquaculture industry is to improve the performance of hybrids compared to their parents under specific environmental conditions. Improvement in production performance in different traits is quite coincidental due to the presence of allelic interaction in hybrids which can provide hybrid vigor or heterosis. Until now, numerous hybrids of fish have been produced naturally or by direct human intervention. Hybrids constitute a significant proportion of some countries’ production for certain taxa. Hybridization has been used in combination with polyploidization to improve developmental stability in hybrid progeny. The results of inter-specific hybridization can be variable and depend on the genetic structure (including the sex) of the parent fish. Detection of hybrid nature of the progeny has a key role in the hybridization practices. Different methods can be used to investigate the true nature of hybrids, such as molecular methods which provide us the possibility to test at early larval stages or even after larval hatching. High precision and accuracy as well as suitable performance test speed make them efficient tools for hybrid detection. Hybridization between different species of food as well as ornamental fish with emphasizing on most important Iranian fish species have been reviewed.

Due to the valuable nutritional properties that exist in aquatic animals, their consumption has been intensified in recent years. Thus, the protein obtained from edible aquatic animals, has a significant contribution in providing the animal protein needed in many parts of the world. Therefore, many efforts are made to increase their consumption among the people by processing them into various products. But the main problem with aquatic animals and their products is the high rate of spoilage and the decline in their quality, which, if the desired storage conditions are not provided, they will be spoiled easily and lose their edible capacity. Due to the high volume of fish that are processed, it is necessary to ensure the quality of the product, by monitoring all the operations before and after fishing so that the fish used, with minimal changes to enter the processing process. In the present article we attempt to examine the main challenges surrounding this issue.