Iranian Journal of Fisheries Sciences
Volume:14 Issue: 4, Oct 2015

A 6 week study was conducted to assess the effects of wood betony (WB), Stachys lavandulifolia extract on growth performance, hematological and biochemical parameters of common carp, Cyprinus carpio. Different levels of the WB extract (0, 2, 4 and 8 % weight per weight, W/W, 0WB, 2WB, 4WB and 8WB) in the diet were used. The results showed that final weight and weight gain were significantly improved by WB (p<0.05), while other growth parameters such as food conversion efficiency and condition factor did not change (p>0.05). There were no significant differences in hemoglobin, hematocrit, mean erythrocytes of hemoglobin, mean erythrocyte volume, mean hemoglobin erythrocyte concentration and white blood cell (WBC) counts (p>0.05), while, red blood cells (RBC) counts showed significant declining trend by increasing the level of the plant extract from control to 8WB (p<0.05). Significant elevation in the levels of total protein, albumin and globulin and albumin/globulin ratio by increasing WB concentration in the diet were observed (p<0.05). Diet enriched by WB could decrease serum level of triglycerides and cholesterol in comparison with the control (p<0.05). Based on the results of this study, it could be concluded that feeding common carp with WB can improve growth and some immunity characteristics as well as lipid metabolism..

Motility parameters of the spermatozoa in most fish species spawning in fresh water like Rutilus kutum lasts for a short time after activation. Ovarian fluid significantly influenced sperm motility (motility duration period) and percent motility (progressive forward motile sperm). Both of these variables generally increased as the concentration of ovarian fluid increased from 33% to 50%, respectively. It is concluded that ovarian fluid enhances sperm movement in this species at appropriate level and thus has the potential to influence fertilization capacity.

Physicochemical properties of surimi and kamaboko obtained of solubility in acid, alkaline and conventional methods were compared. The results indicated that the highest protein recovery was related to solubility in acid, alkaline and conventional methods, respectively. The highest removal of lipid and myoglobin was observed by solubility in alkali. Excretion of total pigment and sulfhydryl groups was not significantly different between solubility in alkali and acid methods. Whiteness of surimi prepared by acid method was more than the other two methods. Electrophoresis pattern in surimi produced by conventional method indicated loss of myofibril and sarcoplasmic proteins through the washing process. Solubility in acid and alkali methods showed myofibril proteins recovery along a part of the sarcoplasmic proteins and disintegration of myosin heavy chain. Physically, study of kamaboko showed that solubility in alkali generated features such as gel strength, expressible moisture, hardness, gumminess and elasticity was superior to the other two methods. About folding test and cohesiveness factor, there was no significant difference between solubility in alkali and conventional methods. In general, solubility in alkali method was better.

A study was carried out to evaluate the probiotic activity of Bacillus subtilis G1 isolated from fermented pickles in growth performance and disease resistance of Hemibagrus nemurus fingerlings at Universiti Putra Malaysia. The probiotic was mixed in feed at doses of 0 (C, control), 3 x 109 (T1) 3 x 107 (T2) and 3 x 105 (T3) cfu g-1 and fed to the catfish fingerlings for nine weeks. Results showed that catfish fed a diet containing 107 cfu g-1 B. subtilis G1 had significantly higher percent weight gain (248.69 ± 3.31%), and better food conversion ratio (1.68 ± 0.03), than those of other treatments. Inhibitory activity of the probiotic B. subtilis G1 against fish pathogens Aeromonas hydrophila and Streptococcus agalactiae was evaluated by well diffusion agar method. Inhibition zones measured showed A. hydrophila and S. agalactiae were 16.13 ± 0.91 mm and 17.5 ± 1.84 mm, respectively, indicating strong inhibitory activity against the pathogens. Three weeks after the feeding trial, the fingerlings were challenged with 0.1 ml containing 106 cfu ml-1 of A. hydrophila by intra-peritoneal injection. After 14 days, the mortality rate of catfish was significantly lower in group T1 (30 ± 5.8%) compared to the control (C) group (56.7 ± 3.3%). The findings of this study proved that administration of B. subtilis G1 can improve growth and disease resistance in catfish.

Black pomfret Parastromateus niger is a commercially important fishery resource in the Persian Gulf but harvesting its stocks lacks genetic identification of populations. AFLP technique was applied to analyze genetic diversity and population structure of 32 fish from coastal waters of Bandar Abbas, Bushehr and Abadan with 7 EcoRI/MseI primer pair combinations. In total, 381 bands were produced of which, 46 were polymorphic (12.07%). Percentage of polymorphic bands was higher in Bushehr samples (91.30%) than in Abadan (84.78%) and Bandar Abbas (73.91%) samples. The highest level of heterozygosity based on Nei’s coefficient and Shannon’s index was observed in Bushehr fish (0.38±0.16 and 0.54±0.21). Observed and effective alleles ranged from 1.73±0.44 and 1.53±0.40 in Bandar Abbas samples to 1.91±0.28 and 1.70±0.34 in Bushehr samples. The average Fst was 0.19 indicating high genetic differentiation among the three locations. Gene flow with mean of 1.93 was the lowest level between Bandar Abbas and Abadan (1.24). Nei's genetic identity revealed the least genetic similarity between the samples of Bandar Abbas and Abadan (0.77). AMOVA analysis demonstrated 81% of the genetic variation within populations and 19% among populations. The UPGMA dendrogram clustered all 32 individuals into 3 groups. In some cases individuals from the same region were grouped together but in most cases, gene exchange was observed to be common among the groups. Analyses provided evidence for genetic differentiation among the three locations, indicating separate populations of black pomfret in the northern Persian Gulf.

Desalination plants are potentially capable of having impacts on coastal marine environments due to the production of wastewater with high concentrations of salts (brine discharge) and some heavy metals. The aim of this study was to examine the concentration of accumulated metals (Ni, Cu, Cd, Fe, Zn, Pb) in the sediments near the brine discharge point in the Chabahar Bay. Twenty one sediment samples were collected from seven stations in summer pre-monsoon and post-winter monsoon, in April and October 2011. The results showed that stations closer to brine discharge points had higher concentrations of metals in the sediment than other stations. Metal contamination in sediment samples was below a critical level with the exception of cadmium with higher values than MAFF, ANZECC and FDEP standards at a maximum of 5.76 mg/kg dry weight. There was a clear decreasing gradient in heavy metal concentrations from station 2 to station 7, especially for Cd, Pb, Fe and Zn. The probable reason for this is the water circulation in the Chabahar Bay.

This study attempts to observe and record early embryonic developments of the orange mud crab, Scylla olivacea. The period taken by the eggs to hatch was 8 days and the colour of the eggs gradually changed from yellow to brown, gray and dark gray. During the embryonic development, the developing embryos reached the blastula stage within 24 hours with a mean egg diameter of 329.91 µm ± 6.62. The embryo developed into the gastrula stage on the 2nd day with a mean egg diameter of 337.10 µm ± 8.37. Eyes were consequently observed on the 3rd day and there was a further increase in the yolk-free portion with a mean egg diameter of 338.16 µm ± 6.57. On the 4th day, the eye-spot became crescent and there was a clearer tissue formation with a mean egg diameter of 358.45 µm ± 14.80. Meanwhile, on the 7th day prior hatching, there were many chromatophores present, mostly dark in colour and the yolk granules had further reduced in size. The heart beats faster than previous days before and the embryo occupied most of the available egg volume with a mean egg diameter of 377.26 µm ± 11.50.

The purpose of this study was to investigate the therapeutic effects of propolis on biochemical and microbiological parameters in muscle tissues of carp (Cyprinus carpio, Linnaeus 1758) exposed to arsenic. A sublethal concentration of arsenic (0.01 ppm) and/or 0.01 ppm propolis were administered to fish for seven days. Biochemical parameters [pH, lactic acid, total volatile basic nitrogen (TVB-N), and malondialdehyde (MDA) values] and microbiological changes (mesophilic and psychrophilic bacteria count) were determined in fillet of carp in control, arsenic only, propolis only and arsenic+propolis treatment groups. Results showed that the levels of MDA, lactic acid and TVB-N increased (p<0.05) while there were decreases total counts of psychrophilic, mesophilic bacteria and level of pH in arsenic group compared to the control group. Additionally, levels of pH, lactic acid, TVB-N, counts of psychrophilic and mesophilic bacteria in arsenic (0.01 ppm)+propolis (10 ppm) group significantly reduced compared to arsenic group (p<0.05). In conclusion, propolis can affects some biochemical and microbiologic functions and quality in the fillet of carp exposed to arsenic.

Diet of adult pikeperch Sander lucioperca, Eurasian perch Perca fluviatilis, northern pike Esox lucius and European catfish Silurus glanis as top predators in aquatic ecosystems in Serbia was investigated during 2011, in order to understand their relationship to their prey and to investigate their food consumption, feeding and assimilation rate, cannibalism, and habitat segregation. Northern pike, Eurasian perch, pikeperch and European catfish were collected in three reservoirs in Serbia. Prey items that were found in all four species included fish, mollusks, insect larvae and crustaceans. A total of 11 taxonomic groups were found, but they were not all represented as a prey in all four species. Eurasian perch were present in the diet of all four predatory fish species, mollusks were recorder only in that of European catfish. Roach Rutilus rutilus and bleak Alburnus alburnus were prey to all species, except northern pike. Chub Squalius cephalus, bream Brama brama and Gammaridae were found only in stomach of pikeperch. Analysis of similarity showed that difference for diet between predatory fish species was significant for their due to significant differences existing between northern pike and pikeperch and northern pike and Eurasian perch.

Genetic diversity of six populations of bartail flathead (Platycephalus indicus Linnaeus, 1758) was investigated using amplified fragment length polymorphism (AFLP). A total of 118 reproducible bands amplified with ten AFLP primer combinations were obtained from 42 fishes that were collected from six different locations in the northern part of the Persian Gulf. The percentage of polymorphic bands was 57.06%. Nei’s genetic diversity was 0.1808±0.2074 - 0.2164±0.1903, and Shannon’s index was 0.2675±0.2949 - 0.3280±0.2727. The results of AMOVA analysis indicated that 66% and 34% of the genetic variation occurred within and among the populations and gene flow was 0.6454. The estimated level of population differentiation as measured by average Fst value across all loci was 0.327. Analyses revealed significant genetic differentiation with low gene flow among the six locations, indicating at least six separate populations of bartail flathead in the northern part of the Persian Gulf.

Randomly selected 320 fingerling of Labeo rohita were collected from Faheem fish farm, Mattital Road, Multan. Groups of 40 fish each were exposed to subleathal concentration of imidacloprid (120 mg L-1) under short (2, 4 and 8 days) and long term (16, 32 and 64 days) conditions to access the effect of this most extensively used pesticide on the body composition parameters of economically most important fresh water fish, L. rohita, in Pakistan. Separate control groups were used for each imidacloprid treatment. It was found that most of the studied body composition parameters remained unaffected during short and long term experimental treatments as compared to their respective control groups with the exception of the 64 days treatment where several parameters including body weight (p = 0.02), dry body weight (p = 0.005), % dry weight (p = 0.001), total water contents (p = 0.04), total fat (p = 0.03), % fat wet weight (p = 0.001), % fat dry weight (p = 0.003), total organic contents (p = 0.04), % organic content wet weight (p = 0.001), total proteins (P p = 0.005) and % protein wet body weight (p = 0.001) had significantly lower values in imidacloprid treated fish as compared to control group. Our results indicated that chronic exposure of imidacloprid can adversely affect the nutritional quality of L. rohita.

The experiment was conducted to determine the effects of different photoperiods and darkness on the growth and survival of juvenile Catla catla in the laboratory for 90 days. Fishes were divided into four aquaria (10 fish per aquarium), and subjected to different photoperiod regimes of 8 hours light: 16 hours dark (8L:16D), 16 hours light: 8 hours dark (16L:8D), continuous light (24L:0D) and complete darkness (0L:24D). The maximum and minimum growth was observed in the group subjected to continuous photoperiod and complete darkness, respectively. The mean body weight of these groups was significantly different (p<0.05) from other groups which was observed from day 60. Survival rate was 100 percent in all the aquaria subjected to different photoperiods except one which was under continuous dark, where 30 percent mortality was recorded. Mean final growth rate, specific growth rate and daily feed intake were maximum in the group subjected to continuous photoperiod and their means were significantly different (p<0.05) from other groups of fish of different photoperiod regime. A continuous photoperiod is suggested for better growth and survival of rearing juvenile Indian major carp, C. catla under controlled conditions.

Growth and reproductive attributes were determined for Capoeta damascina, an endemic fish species from west of Iran. A total of 147 specimens of both sexes were sampled monthly from November 2008 to October 2009. The overall sex ratio was female biased. Males were aged 0-4 years and females 0-5 years. The von Bertalanffy growth parameters were estimated as; Linf=34.81 cm, k=0.27 year-1, t0=-0.65 for males plus unsexed samples, Linf =46.29 cm, k=0.22 year-1, t0 =-0.59 for females plus unsexed samples and Linf =67.52 cm, k=0.12 year-1, t0=-0.79 for whole samples. The length- weight relationships were W=0.021L2.815 for males, W=0.022L2.824 for females and W=0.020L2.836 for combined sexes, all of which exhibited a negative allometric growth. Spawning season started in May, ascending to June and ended in July for both sexes. Length at 50% maturity was estimated as 12.35 cm for males and 15.14 cm for females. Fecundity ranged from 1551 (2 years old) to 20523 (5 years old) eggs per fish. Losing of large individuals and decreasing in size at first maturity were observed in the studied population compared to data reported from other C. damascina populations, which could reflect an effect of overexploitation.

Haemato-biochemical studies in rainbow trout infected with Saprolegnia were carried out under temperate climatic conditions of Kashmir valley to find out the variation in blood parameters. The trial was carried out on 405 cultured rainbow trout fish ranging in length from 47.8 to 69.8 cm and in weight from 1300 to 1920 g. The same experiment was carried out on 2,70000.00 trout fish eggs from November 2010 to April 2011 at a trout fish farm, in Kokernag, India, on account of the susceptibility of eggs to fungal infestation. The infected fish showed signs of lethargy, irritation, loss of appetite, haemorrhages at the base of fins and deep wounds at the sites of severe infection associated with cottony wool like tufts on both the dorsal and ventral sides of the body. The fungi were isolated at high percentages from skin followed by fins and mouth. The haemato-biochemical profile was studied in forty (40) normal and forty (40) infected fish. The haemoglobin content, total erythrocyte count, packed cell volume, lymphocyte percentage, total serum protein, albumin and globulin levels decreased significantly (p<0.05) in the Saprolegnia infected fish as compared to that in the control. The white blood cells, erythrocyte sedimentation rate, mean corpuscular haemoglobin, mean cell volume, heterophill percentage and total serum glucose showed significant increase in the infected fish irrespective of sex. The infection was more pronounced during the winter season (Temp.<10°C) as compared to that in summer (temp.<17°C). Fungi induced stress leads to haemostatic imbalances in fish reflected in the haemato-biochemical profile and can thus be used as an indicator for Saprolegnia induced infection.

In this study, age-dependent changes of sperm quality parameters in Rutilus frisii were investigated. Also, fertilization capacity of breeders was tested using two age groups of males (3 and 4 year old breeders) and one female group (i.e. 4 year old breeders). For fertilization trials, the breeders were crossed randomly among age classes. Between the two age groups, spermatological parameters did not show vary significant differences. Some composition of the seminal plasma such as osmolality showed significant difference and was higher in older fish. Higher fertilization rate was observed when ova were fertilized with 4 years old semen samples. Relationships between sperm motility characteristics (percentage and duration of sperm motility) and chemical properties of seminal plasma were investigated. In this regard, were found between the duration of sperm motility and Na+, and Cl-, respectively. Also, the percentage of motile spermatozoa had significantly positive relationships with the concentrations of Ca, Mg and pH of semen. On the other hand, osmolality of the seminal plasma was positively correlated with protein. Our results shows that selection of broodstock based on age can be used as a simple procedure to achieve higher results in fertilization process; also understanding of such correlations can be useful to evaluation of sperm quality and make media (extender) for dilution of semen and improving sperm motility parameters of kutum.

Reducing dietary protein content in fish feeds will reduce cost of production if growth performance can be maintained. In this study, we assessed the effects of reduced dietary protein content from 33.5% to 27.4% with ideal amino acids profile on the growth, immune parameters, intestinal microvilli length and total ammonia nitrogen discharge of tilapia. After 8 weeks of feeding, growth performance and feed efficiency were not affected by reducing dietary protein content from 33.5% to 30.3%, while fish fed 27.4% CP had the lowest weight gain. Total ammonia nitrogen discharged into the water 9 hours after the feeding was decreased by about 35%. Serum lysozyme activity, blood respiratory burst activity and serum ACH50 were not significantly affected by dietary protein content. Fold height, enterocyte height and microvillus height of proximal and middle intestine were significantly increased with reducing of dietary protein. Results indicated that 3.2% dietary protein content can be reduced, which had no effects on growth performance and immunity of Nile tilapia in practical diet.

In the present study, cadmium (Cd) accumulation capabilities of aquatic macrophytesCeratophyllum demersum, Bacopa monnieri and Rotala rotundifolia were determined after treating both individual and triple macrophytes. The macrophytes were treated with Cd at 0, 0.1, 1 and 10 mg/L concentrations in a controlled chamber for 12-days. Cadmium accumulations increased with increasing Cd concentrations in all macrophytes. Bioconcentration factor (BCF), which indicates the efficiency of the macrophyte to accumulate Cd, decreased with increased external Cd concentrations. When compared to single macrophyte applications, reductions were observed in Cd accumulation of the combined macrophyte treatments. The maximum Cd accumulation was recorded in R. rotundifolia followed by C. demersum and B. monnieri in both single and combined macrophyte applications. Consequently, the macrophytes in both applications proved highly effective in the accumulation of Cd. Thus, they may be used especially in the abatement and monitoring of Cd pollution.

The food and feeding habit of beardless barb, Cyclocheilichthys apogon (Valenciennes, 1842), from family Cyprinidae was investigated by stomach content analyses of 374 collected fish in two consecutive reservoirs; Temengor and Bersia Reservoirs which are separated by Temengor Dam. The main aim of this study was to compare the stomach contents of C. apogon between these two reservoirs in wet and dry seasons. Results showed that C. apogon is omnivorous based on the moderate value of relative gut length. The main food items contained in their stomach were Oligochaeta, Chironomidae and detritus which made up over half of the stomach contents. Other food items, such as Cladocera, Crustacea and Gastropoda, supplemented the main food and were consumed in much smaller amounts. There were specific differences in the food preference between Temengor and Bersia populations i.e. Oligochaeta was the most preferred in the former while Chironomidae in the latter, but the general pattern was similar in both. There was no statistically significant difference (p>0.05) in frequency occurrences of food items in diet composition between the two reservoirs during both wet and dry seasons. Therefore, the seasonal feeding activities of C. apogon in Temengor Reservoir were relatively similar with those in Bersia Reservoir. In conclusion, for the present Temengor Dam does not affect the nutritional habit of C. apogon in Bersia Reservoir.

The present study explored the embryonic and larval development of an endangered fish species Nandus nandus and resolved larval growth performances with the dietary supplementation of different types of lipids. Fertilized eggs were collected from fiber glass tanks immediately after spontaneous spawning of N. nandus, which were fed with a 1% phospholipid (squid meal) supplemented diet for 3 months. Fertilized eggs were transparent, spherical, yellowish and sticky in nature. The first cleavages of eggs were observed 0.3±0.01 h post fertilization at 26oC water temperature. Hatching started around 18 h post - fertilization and newly hatched larvae were found to be 1.2±0.1 mm in length. First feeding started 64.0±0.30 h post hatching. After rearing for 10 days, they were divided into 4 groups and separately fed with only dry tubificid worms, 1% docosahexaenoic (DHA) supplemented with dry tubificid worm, 1% phospholipid supplemented with dry tubificid worm and live tubificid worms as treatment I, treatment II, treatment III and treatment IV, respectively. After 50 days of the trial, larvae of treatment II showed significantly (p

In this study Escherichia coli DE3 containing expression vector (pET21a) with cloned Persian sturgeon growth hormone (psGH) gene was grown in 10 mL LB broth on a 150 rpm shaker, at the temperature of 37 °C. At the late log phase (determined by OD standard curve) 100 μL isopropyl β-D-1-thiogalactopyranoside (IPTG) was added for induction of GH synthesis. Samples were taken every 2 hours and after bacterial cells lysis crude extracts with recombinant proteins inclusion bodies (IB) were loaded on 15% SDS-PAGE gel. Thenafter staining, comparative concentrations of rpsGH were measured by densitometric scanning of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) gel it was more than 90 %. The maximum yield of GH was observed after 4 hours of growth. To recover active psGH from inclusion bodies we used imidozole to obtain most of the total recombinant protein in the soluble fraction. Purification of 6xhisN tag recombinant psGH has been performed using affinity chromatography where nickel was bound to an agarose bead by chelation using NTA (nitrilotriacetic acid) beads. The overall yield of the purified monomeric psGH was approximately 50% of the initial IB proteins. The purification manipulations including IB isolation and solubilisation, protein refolding by dialyze and affinity chromatography ensure yields of biologically active psGH up to 30%. This study shows that, the affinity chromatography is a powerful and very specific method for recombinant proteins purification of psGH.