IRANIAN JOURNAL OF FISHERIES SCIENCES
Year:2017 | Volume:16 | Issue:2|Papers Count:34

The application of nanotechnology in drug delivery and a variety of supplements is very impressive. In this regard, the use of this knowledge can be effective in the performance of medicinal plants in aquaculture. In the present studyAloe vera was extracted and its nanoparticles were produced. Three levels of Aloe vera nanoparticles in Siberian sturgeon (Acipenser baerii) were evaluated for the effects on growth performance, survival rate and body composition. A total of 360 Siberian sturgeon(A.baerii) with an average of 10.95 ± 0.04 (g) randomly divided into four treatment groups with three replicates each. The treatment groups were fed with diets that included 0% (control), 0.5, 1 and 1.5% of Aloe vera nanoparticles for 60 days. Weight gain, initial body weight, condition factor, feed conversion ratio, specific growth rate, protein efficiency ratio, survival rate, and body composition (protein, lipid, carbohydrate, ash and moisture) were measured and compared among the fish in the different groups. The results showed that growth indices of fish fed the Aloe vera nanoparticles were higher than the control diet, so that the difference between the control group and 1%Aloe vera nanoparticles was more than that in other treatments. In each of the body composition parameters, no significant differences were observed among the treatments and control groups (p>0.05). Considering that there are no significant differences in results between 1% and 1.5%Aloe vera nanoparticles, the results showed that adding 1% Aloe verananoparticles to the fish diet improves the growth factors of Siberian sturgeon.

This study is attempted to compare the number of rings and circular scales that are formed during various ages on Liza saliens. Sampling was carried out monthly during 2012-2013 using beach sine fishing nets. 102 specimens of different sizes were collected and transferred to the laboratory in boxes containing ice. The age of fish was determined by the number of annual rings as well as, the number of rings in each annual area. The distance between rings in each annual area was also measured. The results showed that the maximum growth was demonstrated in the first and second years. In the first year of life, the scale radius was nearly 2823.3±366.5(μm) which decreased to 1223.9±236.0(μm). The result indicated that 48 percentage of growth scales occurred in the first year and this value is only 21.8% in the second year. The number of growth rings in the annual regions decreased with increase in age. The result demonstrated that the average number of rings was 95.5±17.6 in the first life year of the fish. If you take into account the number of growth ring through years in comparison with the number of days in a year, it is clear that one ring was nearly made in four days in the first life year and it gradually reached 7.5, 15.9, 21.9 and 31.7 in the second, fourth and sixth years of life, respectively. One ring was approximately made in each month at higher ages.

To describe the morphological and histological changes during the annual reproductive cycle of the gonads of Cyprinion tenuiradius, a total of 341 specimens (102 female and 235 male specimens) were collected monthly from the Rudbal River (in the Qarah Aghaj sub-basin, the Persian Gulf basin), Firuzabad, Fars Province, southern Iran. The randomly sampling was adequate to collect males and females at the immature, mature, spawning-active, and non-active phases of reproduction. Five ovarian and fivetesticular maturation stages (I-V) were described using macroscopic and light and electron microscopic criteria. Also based on the histological examination, six types of ovarian follicles (A-F) and five types of testicular cells were designated. The largest ovarian follicles were found in the stage V of ovarian developmental stages in females with mean body weight and standard length of 22.27 g and 95.13 mm, respectively. The highest number of sperms was observed in the stage V of testicular developmental stages in males with mean body weight of 25.67 g and mean standard length of 97.83 mm. Based on the percentage of late ovary and testis maturation stages (IV, V) and high frequency of large oocytes and sperms it was concluded that the Qarah Aghaj botak spawns once a year during spring and the beginning of summer from April to July.

In the present study, the effects ofChlorella vulgaris on blood and immunological parameters of Caspian salmon (Salmo trutta caspius) before and after exposure to Viral Nervous Necrosis (VNN) virus were examined. In this regard, four treatments in triplicate were chosen. Groups included one control and 3treatments (T1, T2 and T3).Fish in control group, T1, T2 and T3 were fed diets supplemented with 0, 1×108, 2×107 and 3×106 chlorella/450 g of food respectively, for sixty days. In addition, a virus supernatant was prepared from infected wild golden grey mullet (Liza auratus) and used for virus challenge ofS. trutta caspius. Virus was injected intraperitoneally and blood samples were collected before and 14 days after the challenge. Immunological (IgM, C3, C4, total protein, respiratory burst, albumin and lysozyme) and changes in blood parameters (RBC, WBC, Htc, Hb, MCH, MCHC and MCV) were also measured.Results showed that C. vulgaris could act as a natural immunestimulant. Also, the alteration trend in hematological and immunological parameters showed that experimental fish could be considered to be resistant to VNN virus after exposure and fish treated withC. vulgaris were more resistant in comparison to those in the control group. The dose used in T1 (1×108 chlorella/450 g food) was the most effective approach with significant differences.

Age and growth of Mesopotamian barb, Capoeta damascina, were studied in the Zayandehrud River, in central Iran, from March 2007 to April 2008. Among the 689 specimens studied, age groups in males ranged from 1+ to 9+ and that in females ranged from 1+ to 10+. The sex ratio (1M:1.6F) was not significantly different from 1:1 ratio. Maximum fork length and weight was 39 cm and 1,115 g for males and 54.2 cm and 2,340 g for females. In all age classes, females were larger than males. The most frequent age groups were 3+ in males and 4+ in females. The highest value for condition factor was observed in June. The growth of C. damascina was described by von Bertalanffy growth curve as k=0.01, L¥=56.2 cm, to=-0.63 for males and k = 0.05, L¥=117.1 cm and to =-0.43 years for females. The length-weigh relationship was described as W=0.0169L2.95 (r2=0.98) for males and as W=0.0155L2.99 (r2=0.99) for females, indicating an isometric growth pattern in both sexes. Growth performance index j was estimated as 5.73 for males and 6.53 for females, indicating a faster growth rate in females.

Due to the recent destructive pressures on the Caspian environment, an effect on phytoplankton communities is expected in different aspects such as cell size and form. This paper aims to survey the size and form in the dominant phytoplankton species in the years of 1996, 2001, 2006, 2009, 2011 and 2012 in the Iranian coast of the Caspian Sea. Results of current study showed that the dominant species and along with it their sizes and forms remained quite similar in the fall of different years, but the greatest shift in size and form were observed during spring, summer and winter. It is suggested that these changes reflect an ecological disturbance and instability in the Caspian environment.

The freshwater crayfish of the Aras Reservoir is an important economic fisheries resource of West Azarbaijan, Iran. This study was conducted to evaluate the prevalence of parasitic infestation of Crayfish seasonally in this area in 2010. Among 390 different sizes ofAstacus leptodactylus which were examined, a range of ectocommensals or ectosymbionts from a number of different phyla including 9 orders and 11 classes infested the different anatomic units of the surface and appendages such as gills, head, thorax, abdomen, walking legs, uropod, telson, antennae and antennulae of freshwater crayfish. Common groups such as peritrich ciliates, suctorian ciliates, free living nematodes, branchiobdellids, and algae, copepods, rotifers and oligochaetes have also been observed in association with freshwater crayfish.

The gobiesare non-commercial fishes in the Iranian waters of the Caspian Sea for whichpopulation dynamics and stock status are poorly known. In this survey, we tried to define species diversity and catch per unit effort (CPUE) of Gobiidae by using beach seine nets in Salmanshahr, the southern Caspian Sea. From March 2011 to April 2012, 224 specimensrepresenting 4 gobiid species, belonging to genus Ponticola and Neogobius, were caught. The deepwater Goby, Ponticola bathybius (Kessler, 1877), was the most abundant species with 92.8% frequency. The highest catch per unit effort of gobiid fishes was obtained in spring. The species diversity was highest in spring according to Shannon’s index.

The Acehnese mahseer, locally known as keureling, Tor tambra is one of the highest economically valued freshwater fishes found in Aceh waters. The culture of T. tambra was initiated in Aceh Province, Indonesia more than five years ago. However, the growth rate in captivity has been low, probably due to feeding problems. Hence, the objective of the present study was to evaluate the optimum level of dietary protein in commercial feeds for growth improvement. Three commercial feeds with different levels of protein i.e.20%, 25%, and 30%, were tested in this study. A total of nine semi-concrete ponds were used and each pond was stocked with 15 mahseer fingerlings. The experimental fish were fed at a ratio of 3% of body weight twice a day for 60 days. The ANOVA tests revealed that dietary protein levels significantly affected growth performance, protein efficiency ratio, protein retention efficiency and lipid content in carcass but did not significantly affect survival rate and protein content in the carcass (p>0.05). The results showed that the growth performance, survival rate, and protein content increased with increasing protein level in the diet and the best composition was 30% of protein.

In this study, fish meal (FM) was replaced by the black soldier fly maggot meal (BSFM) with replacement levels at 0%, 25%, 50%, 75% and 100%. The feeding trial was conducted for 56 days and the effect of each replacement level on the growth performance, feed utilization, body composition and survival of the experimental fish was assessed. All the experimental diets were well accepted by the fish. No mortality was observed during the experimental period. Diet 3 resulted in the highest weight gain and SGR values of 8.74±0.18 and 2.43±0.04% respectively. FCR and PER values obtained for Diet 3 were also better compared to that with other diets. Although there were no significant differences in crude protein content among fishes fed different diets (Diet 1 to Diet 5), fish fed Diet 3 showed significant (p<0.05) increase in crude protein content at the end of the experiment. Based on these results, it may be concluded that BSFM can be used to replace FM with up to 50% replacement without causing adverse effects on growth and feed utilization parameters.

The effects of two diets, a control diet (commercial feed with 39% crude protein) and an experimental diet (prepared based on 42% soybean meal with 38% crude protein), on growth performance of western white shrimp (Litopenaeus vannamei) in six 0.4-ha-earthen ponds (three replications per treatment) with 25 per m2 density, were investigated. There was no significant difference in final weight (mean final weights were 15.7±0.88 and 15.6±0.52 g for the experimental and control treatments, respectively) between the treatments during the 115 days rearing period. There were no difference in FCR: 1.80±0.08 and 1.76±0.06, protein efficiency: 1.46±0.01 and 1.45±0.05, SGR: 2.38±0.04 and 2.38±0.03, final production: 2853.58±64.14 and 2864.83±168.57 kg/ha and survival rate: 91±1.78, 92±2.41% between experimental and control treatments, respectively (p>0.05) but net protein utilization in experimental treatment (17.05±0.38 g) and in the control (11.80±0.26 g) revealed significant differences (p<0.05). It is concluded that the experimental feed with 42% soybean meal was more efficient than the commercial feed on some growth parameters of western white shrimp.

The Japanese threadfin bream, Nemipterus japonicus, the most abundant and crucially economicNemipterus species is widespread throughout the Indo-West Pacific. The species has been studied widely for various aspects but genetic studies are scanty. This preliminary study contributes to the species phylogeography through the study of the genetic diversity and historical demography ofN. japonicus populations from the Persian Gulf and Indo-West Pacific based on cytochrome c oxidase subunit I (COI) gene sequence. Grouping of the data into phylogenetic trees indicated that the Japanese threadfin bream consists of two reciprocally monophyletic phylogroups with 2.3% net sequence divergence which may qualify as cryptic species: clade I, consists of two subclades (Ia and Ib) occurs in the Persian Gulf and Western India, and clade II, which is restricted to the South China Sea. Historical and demographic hypotheses were raised to explain the observed phylogeographic pattern and population structure. Among the possible key mechanisms, sea level fluctuations driven by glacial episodes of the second half of the Pleistocene Epoch appear to have played an active role in initiating major phylogeographic separation. Apart from presumptive Pleistocene vicariance, a trend of increasing genetic differences with increasing geographic distance (i.e., isolation-by-distance) and regional differences in breeding season were also proposed as possible alternative scenarios. Since the baseline knowledge on the intraspecific genetic diversity and management and evolutionary significant units is the first step before any action to be taken, the basic findings provided by this research are particularly relevant to conservation efforts, fishery management and stock assessment.

The formation and regulation of vertebrate endogenous intestinal microbiota has been widely studied as the microbiota plays a crucial role in the host nutrition, development, and health. Despite the importance of microbiota for host health, it is still unclear whether the endogenous intestinal microorganisms are genetically distinct or whether they are genetically related with each other in different host individuals. In the present study, the dispersal situation of the endogenous intestinal bacteria in grass carp was investigated by constructing bacterial 16S rRNA gene clone libraries. The results indicate that the bacteria harbored in the grass carp gut could be separated into the following two groups: a- the private operational taxonomic units (OTUs), which includeCetobacterium somerae, Aeromonas jandaei, Citrobacter freundii, Achromobacter xylosoxidansand Bacteroides species; b- the shared OTUs, which includeVibrio cholerae, Plesiomonas shigelloides and Pasteurella speices. The results obtained in this investigation provide valuable information for assessing the mechanism of spread of the endogenous intestinal bacteria, especially the pathogenic ones.However, the mechanisms involved in different modes of bacterial dispersal in the grass carp gut still require further research.

In this study, the essential oil (EO) ofPistacia atlantica subsp. kurdica was added at the rate of 10 g/kg of daily diet of rainbow trout and its effect on gut microbiota (Enterobacteriaceae, Lactobacillus spp., total count), growth performance and antioxidant status of rainbow trout fillet was investigated. Sixty apparently healthy rainbow trout with an approximate weight of 150 g ±3.5 were randomly divided into treatment and control groups. Physical and chemical conditions of water were adjusted to optimal for fish farming and sampling was done after 3 months. The results showed that feed conversion ratio in the control group was significantly (p<0.05) lower than that in the treatment group. The total number of intestinal bacteria was significantly reduced in the treatment group (p<0.05), but the amount of this reduction in Lactobacillusspp. was lower than other bacteria. The oxidative status of fish fillet in the treatment group was not significantly different from that in the control group (p>0.05) after 1 and 7 days cold storage (3oC). According to the obtained results, the EO of Pistacia atlantica kurdica at this dose is not advised for increasing the shelf life of meat and growth performance of fish.

Changes in proximate composition, colour and textural characteristics of ozone-processed shrimp as affected by combined effects of increasing ozone exposures and iced storage were investigated and for the first time. Whilst proximate composition comprised of fat, moisture, and protein contents and colour comprised of L*, a*, b* and metric chroma (C), the texture comprised of adhesiveness, fracturability and hardness parameters. Essentially, increasing ozone exposures were safely discharged via commercially available domestic ozone facility. Notably, the storage study lasted for up to eleven days. The results showed that the differences in proximate contents appeared superficial with increasing ozone exposures and iced storage. However, it was the colour, adhesiveness and fracturability attributes that showed noticeable effects (p<0.05) even though the hardness texture resembled in some tested samples (p>0.05). It is plausible that the behavior of adhesiveness and fracturability of ozone-processed shrimp samples may well be complementing those of hardness textures. Overall, the data provided by this study objectively and realistically demonstrates the promising food technological potentials of domestic ozone facilities.

The study was conducted for 134 days. Common carp fry (60g ± 0.3g) were fed using two different diets containing only plant protein sources, without any animal protein inclusions. Diets were administered by two different methods: an automatic band feeder (diet 28.7 F and 28.15 F) for 12 hours a day (9.00 a.m. - 9.00 p.m.) and by hand (diet 28.7 H and 28.15 H) once a day (at 9 am). Weight, Specific Growth Rate (SGR), Protein Efficiency Ratio (PER), Fat Retention Index (FR) and Protein Retention Index (PR) were statistically higher in fish fed with the automatic feeder. On the contrary, the value of FCR was statistically higher in fish fed by hand. Diet composition did not have significant influence on growth performance. Survival rate was not statistically different among groups (85-96%). There was no significant effect of feeding method or diet on meat quality, such as color and fat content.

The effect of Persian bee propolis and pollen extracts on innate immune response of rainbow trout (Onchorhynchus mykiss) was investigated. Fish were fed diets containing 1% Pollen, 1% propolis and combination of the two immune-stimulants (0.5% Pollen and 0.5% propolis) as treatment groups and fed without the two immune-stimulants as positive and negative control groups for 4 weeks. The effects of different stimulants at different weeks (Time × stimulants) were analyzed with the Repeated Measures ANOVA. The first-four groups were then subjected to Aeromonas hydrophila for 5 days. The phagocytic activity, respiratory burst activity, Plasma Total Protein and cumulative mortality were monitored. The results showed that fish fed diet containing 1% propolos or 0.5% Pollen+0.5% propolis enhanced non-specific immunity including respiratory burst activity, phagocytosis but decreases the mortality in challenging with A. hydrophila by 45 and 65%, respectively.

The present research was designed to study and compare the biochemical parameters in Labeo rohita due to exceptional nutritional value of this fish as a protein source in developing countries. The protein and heavy metal (Zn, Cu, Ni) activities were determined spectrophotometrically. The proximate analysis of L. rohita collected from different localities of Pakistan revealed that the protein (19.97%) and ash contents (1.76%) were highest in hatchery L. rohita while the fat (0.84%), carbohydrate (5.39%) and dry matter contents (24.11%), were maximum in the river L. rohita. In comparison to the hatchery and river L. rohita, the moisture contents (81.42%) were the highest in farmed fish. During enzymatic analysis, maximum activities of the peroxidase, a- amylase and mutarotase were recorded in hatchery fish whereas the catalase and superoxide dismutase activities were found to be the highest in farmed fish. The maximum accumulation of Cu and Ni metals were observed in hatchery fish and least in farmed fish and the highest Zn accumulation was observed in river fish. Analysis of variance on catalase, peroxidase, a-amylase activity and metal accumulation showed statistically significant differences at p<0.05 among sampling sites and fish organs and interaction between sampling sites and fish organs.

This study focuses on the factors influencing consumer’s decision in fish consumption in Erzurum Province of Turkey. The data were obtained from 384 households who live in urban areas of Erzurum Province in 2012. The sample size of the study was determined by Unclustered Proportional Sampling Method. Analytic Hierarchy Process (AHP) was used to determine the most suitable type of fish for households. The main aim of this study was to determine the factors that influence the type of fish chosen and the most desired type of fish for consumers. The households consist of 4.5 individuals on average, with fish consumption at 6.5 kg per annum per capita. Their choice of fish was based on taste (38.4%), nutrition (23.5%), price (21.4%) and fishbone (16.7%). Considering these criteria, the most desired type of fish for the consumers was Anchovy.28.4% of households prefer Anchovy, 20.3% prefer Trout, 16.7% prefer Sea Bream, 12.5% prefer Horse Mackerel (Scad), 11.2% prefer Sea Bass and 10.9% prefer Atlantic Bonito. As a result, the national companies marketing fish in the research area need advertisements that inform the consumers about the utility and benefıts of all fish types.

In order to estimate responses of growth rate and growth hormone of Clarias gariepinus to stocking density, fish (initial weight 30.71 ± 0.89 g) were stocked in 120-L tanks at densities of 35, 65, 95, and 125 kg/m3 for 60 days. On day 30 and 60, the fish growth rates were measured, pituitary growth hormone (GH) mRNA levels and serum GH concentrations were examined by real-time qPCR and ELISA technique, respectively. From day 0 to day 30, there were significant decreases in specific growth rates and relative weight gains at higher densities (95 and 125 kg/m3) compared to that at lower densities (35 and 65 kg/m3), whereas no significant effects of stocking density on the two indexes during the day 30−60 were detected. On day 30, GH mRNA levels were unaffected by stocking density, while on day 60, GH mRNA levels were significantly lower at the density of 125 kg/m3 than in the two lower densities. Serum GH concentration increased with decreasing stocking densities but only significantly between 35 kg/m3 and the other treatments on day 30. However, there were no significant differences between two lower densities as well as between 65 kg/m3 and 95 kg/m3 treatments on day 60. These results implied that effect of stocking density on SGR and RWG of C. gariepinus weren’t uniform in different growth periods and a weak positive correlation was observed between growth rate and GH in C. gariepinus in the present study.

A series of two experiments was conducted to study the optimum dietary protein level and protein to energy ratio of lemon fin barb hybrid larvae. In Experiment 1, five isocaloric diets (4700 kcal per kg) ranging from 40 to 60% protein in 5% increments were fed to triplicate groups of lemon fin barb hybrid larvae (initial weight: 0.10 ± 0.01 mg per fish) for 21 days. Weight gain of fish was proportional to the protein content of the diet up to an incorporation rate of 50%. Among formulated diets, the diet with 50% protein produced the highest weight gain (4.26 ± 0.03 mg). The dietary protein level that yielded maximum growth was 52.1% based on a broken-line model estimation of weight gain. Based on these results, two dietary protein levels (50% and 55%) were used along with three energy levels (4500, 4700 and 4900 kcal per kg diet) at each protein level in Experiment 2. The survival of fish fed diets containing 55% protein was significantly lower (p<0.05) than that of fish fed diets containing 50% protein regardless of the energy level. Weight gain of fish was significantly (p<0.05) different at all dietary protein and energy levels. The best growth was observed in larvae fed diet 3 containing 50% protein with 4900 kcal/kg energy with the highest weight gain (3.12 ± 0.00 mg), feed conversion ratio (0.87 ± 0.02) and protein energy ratio (97.35 mg/kcal).

Survey on zooplankton composition was studied during June 2015 to March 2016, by selecting six stations along the coastal waters of Bushehr (the Northwest Persian Gulf). Twenty four zooplankton taxa were identified, and the different zooplankton groups represented twenty-one families. Copepoda was recorded with the most abundance (53.30 %) followed by Malacostraca (32.87 %), which in turn was followed by Sagittoidea (7.44 %) and Appendicularia (6.39%). A major peak of 189.34 N/m3 was observed in February-2016 with 53.25% contribution from Copepoda. Among Copepoda, Labidocera sp. was the major contributor to this peak. Appendicularia was the comparatively less represented group, being chiefly represented by Oikopleura dioica. Labidocera sp., Oithona plumifera which were common in most of the stations. This common distribution were observed for Malacostraca, namely Lucifer hanseni (mysis I), Upogebia sp. (zoea I), Parthenope sp., Ilyoplax frater (zoea VI), for Sagittoidea, namely Sagitta enflata, Sagitta neglecta and for Appendicularia, namely Oikopleura dioica. The mean Shannon's diversity index (H') and evenness were 1.36±0.43 and, 0.68±1.17, respectively. The highest Margalef's index was recorded in station-6 (2.72±1.32) and the lowest in station-2 (1.98±0.89). According to non-significant differences between temporal and spatial zooplankton density and Shannon’s index, from an ecological point of view, it seems the study area is unique and the zooplankton composition is homogenous.

Length-weight relationship and condition factor wereestimated in seven fish species, includingBarbus cyri, Capoeta gracilis, Alburnoides eichwaldii, Pseudorasbora parva, Ponticola cyrius, Cobitis keyvani and Acanthalburnus microlepis from Shahrbijar River, Guilan Province, Iran. A total of 416 specimens ranging from 18 to 135 mm in total length and from 0.06 to 19.25 g in total weight were collected. Based on the results, growth coefficient values “b” ranged from 2.615 (in B. cyri) through 3.001 (in A. microlepis). All length-weight relationships were significant (p<0.05), with r2 higher than 0.819. Thefive species viz. C. gracilis, P. parva, C. keyvani, P. cyrius, and B. cyri showed allometric (b<3<b) while two species viz. A. microlepis and A. eichwaldii showed isometric (b=3) growth patterns. Condition factor ranged from 0.57 (in C.keyvani) through 1.11 (in P.cyrius). All linear regressions were highly significant (p<0.05). The present study provides the first baseline information on the length -weight relationships of the seven fish species from Shahrbijar River which may be useful for further fisheries management of these species.

The purpose of this study was to evaluate the effects of aluminum on the tissue enzymes of gills, liver and muscles in common carp. In this study, the effects of sub lethal levels of aluminum on metabolic enzymes, Aspartate aminotransferase, Alanine aminotransferase and alkaline phosphatase (AST, ALT and ALP) in organs including gills, liver and muscles of common carp (Cyprinus carpio) were evaluated after 24, 48, 72 and 96 h exposure under laboratory conditions. Tissue extracts were prepared from each group. Enzymes were measured using commercial kits and auto-analyzer Selectra-PRO. According to statistical data analysis, it was found that the activity of this enzyme in tissues increased significantly compared to that in the control group. AST enzymes in the liver and muscle increased significantly but were reduced at 96 h. ALP levels in muscle tissue significantly increased at 72 h but were reduced at 96 h. The alterations in the activities of these enzymes indicated that the presence of aluminum interfered with transamination and metabolic process in tissues. As a biomarker in various organs, it can also be useful for toxicology.

This study examined the effects of feeding of two dietary probiotics on growth performance and feed utilization, intestinal colonization and related health criteria, biochemical parameters, hematological indices, and immune parameters and protection against Yersinia ruckeri in Oncorhynchus mykiss during a period of 56 days. The study included 3 groups: 1 (a control group of fish, 2) a group of fish fed with a basal commercial diet supplemented with 2 × 106 CFU g-1 Pediococcus acidilactici (PA-group and 3) a group of fish fed with a basal commercial diet supplemented with 2.5 × 108 CFU g-1 Enterococcus faecium strain IR5 (EF-group). Each group was run in triplicate. The PA-group and EF-group showed significant improvement with respect to WG, SGR, FCR, PER, lactic acid bacteria (LAB) (%) in intestinal, intestinal colonization (log CFU g-1), survival (%), RBCs, WBCs, hematocrit percentage (Hct %), and respiratory burst activity (RBA) levels, each of which was significantly higher than that in the control group (p<0.05). The WG and PER in the EF-group were significantly higher than that in the PA and control groups (p<0.05). Levels of immune-system response across a variety of measures, some of the measured hematological indices, LAB (%) in intestines, and survival rate (%) were higher in the PA group than that in the EF group on 56th days of feeding. Mortality in the PA group (20%) and EF group (33.3%) were significantly lower compared with that in the positive control (73.3%) during the 10 days following exposure to Y. ruckeri (p<0.05).

The by-product from tuna processing is a potential source of edible protein. Therefore, it is very important to extract protein from such raw materials for human food. In this study the optimum pH for protein extraction from tuna by-products was optimized by using isoelectric solubilization and precipitation processes. The Response Surface Methodology (RSM) and the single factor model were used for optimization of the protein extraction process. From ANOVA (one-factor design) tests, significant effects were detected for process variables, functional properties and stability between tuna protein isolate prototypes extracted at acidic and alkaline pH, the latter having the least Total Volatile Basic Nitrogen (TVB-N) and Thiobarbituric Acid Reactive Substances (TBARS), but the highest Water Holding Capacity (WHC), hardness, cohesiveness, springiness and viscosity values. The highest yield percentage was found for the alkaline aided process, too. The alkali-aided process recovered proteins of higher whiteness than the acid-aided process. Accordingly the optimum pH of protein extraction was obtained. The model was then validated and maximized based on the functional properties, stability and recovery yield data. Under the optimized pH, the experimental values were in good agreement with those predicted by the software. Then the properties of the optimum prototypes were compared to the fish protein isolated from different by-products. The results suggest that the proteins recovered from tuna processing by-products could be a valuable source of protein ingredient for fortification/ developing formulated ready-to-eat products.

Gibel carp is a very successful invasive fish species in the waters of Georgian inland and the only fish species in Lake Madatapa. However, almost nothing is known about its biology and morpho-ecological peculiarities at the national level and even the distribution data is not documented. For the first time, we studied the population characteristics of gibel carp in Lake Madatapa (South Georgia) with the aim to reveal the extent of its morphological variability, sex ratio, length-weight relationship and its parasitic community. We showed that the gibel carp population in Madatapa Lake has typical morphological characteristics. The sex ratio is significantly female biased (1/1.8) and the length-weight relationship is within the published margins. The gibel carp population is under the heavy parasitic load, but only two parasitic species (one cestoda and the other digenean species) affect the fishes. Within the framework of the obtained results, we discussed future research needs concerning the gibel carp in the lake.

The snail’s specie, Oncomelania quadrasi, is found abundantly in fresh water fish ponds of Punjab. It is an intermediate carrier / host of various digenetic trematode parasites which causes many serious fish diseases in aquaculture ponds. The purpose of this study was targeted for controlling these snails in aquatic environments through chemical control strategies using copper sulfate as an eradicant. Mainly three trials were conducted to determine the effectiveness of copper sulfate against this snail sp. in laboratory aquaria conditions. Trial I involved the copper sulfate treatment sprayed directly for reductions of snails present on the upper moist layer of soil. Trial II was demonstrated for reductions of the snail densities buried under the depth of 8-16 inch layer of soil. Trial III was managed to study the copper sulfate toxicity on the survival of snails and Labeo rohita present together in the same aquatic media. The study indicated that copper sulfate was effective for eradication of the snails in all conditions whether present on the wet edges / moist soil surfaces, buried in the soils or present in the aquatic environment with fish, however, with varying degrees and intensities.

Introduction: Ribbonfishes are typical inmates of pelagic waters of the world oceans and it is a cosmopolitan species (Parin, 1968., 1988; Nakamura and Parin, 1993). It is a slim…

Introduction: Information on length-weight relationship (LWR) is useful for fishery management and stock biomass assessment (Froese, 1998; Froese and Pauly, 2000; Gonzalez Acostaet al., 2004; Mahmood et al., 2012). Fish growth pattern is determined using the slope value (b) obtained from the LWR regression (Froese, 2006), and the differences in fish well-being between genders and locations are related to the variations in condition factor (K) (Abdoli et al., 2009). However, little is known about the morphometric changes, LWR and condition factor in many gobiid species that live in the muddy flat in the Mekong delta…

Introduction: Microalgae are a wide group of photosynthetic heterotrophic organisms consisting of vital amino acids, protein, minerals, vitamins, chlorophylls and some forms of antioxidants and bioactive substances (Yamaguchi, 1996; Kwaket al., 2012)…

Introduction: Fishes are a valuable source of dietary protein and minerals for seafood consumers and are also used in pharmaceutical products (Mozaffarian, 2009). Over the past several decades aquatic ecosystems have been extensively contaminated with pollutants released from domestic and industrial waste waters and other anthropogenic activities in Khuzestan…

Introduction Loliginid squids occur in temperate and tropical coastal waters where they have been considered economically important (Valinassab et al., 2006; Anderson, 2000)…

Introduction Water, being the source of life, contains many life forms. The number and diversity of algae, which constitutes the first link of the food chain, affect all living things within the aquatic environment including fish. With its streams and lakes that cover an area of approximately 10000 km2, Turkey has very important internal water resources. About 135 of the wetlands within the borders of Turkey have international importance. Twelve of those have been declared as Ramsar areas (Anonymous, 2009)...