kourosh sarvi moghanlou

The present study was carried out to investigate the effect of replacing soybean meal with canola fermented by Bacillus sp. isolated from Caspian Sea sediments on the liver and intestine tissues of Nile tilapia fingerlings. A total of 225 spicemns with an average weight of 1.9±0.05 g were fed five different experimnetal diets including, treatment 1, diet without fermented canola, treatment 2, diet containing 12.5%​ fermented canola, treatment 3, diet containing 25% fermented canola, treatment 4, diet containing 37.5% fermented canola and treatment 5, diet containing 50% fermented canola, for 8 weeks. The results revealed that there were no statistically significant differences regarding pathological changes in the liver tissue such as hepatocyte degeneration, liver fatty change, inflammation, disorganized hepatocytes and haemorrhage among different experimnetal groups (P>0.05). Intestinal tissue examination also showed that no significant differences were observed regarding inflammation and tissue necrosis scores (P>0.05). In conclusion, it was possible to completely replace soybean meal by fermented canola meal in Nile tilapia fingerlings diet to the extent that the product constituted 50% of the finished feed.

The effect of dietary administration of combination of hydro-alcoholic extracts of turmeric (Curcuma longa L.) and thyme (Zataria multiflora Boiss) on growth performance, nutritional parameters, digestive enzymes activity and antioxidant properties of rainbow trout (Oncorhynchus mykiss) was investigated. Three experimental diets including basal diet (control group) and diets containing 0.5% and 1.5% of combination of turmeric and thyme (ratio of 1:2) extracts were prepared. A total of 234 juveniles of rainbow trout were randomly divided into three experimental groups in triplicates (providing 26 fish per replicate) and reared for eight weeks. Feeding diets contained 0.5 % of the extract increased the feed efficiency ratio and condition factor of rainbow trout compared to the control group (P<0.05). Supplementing 1.5 % plant extract increased the Average Daily Growth (ADG) of the fish in comparison to control group (P<0.05). Both dietary levels of the extracts increased protein productive value and lipid productive value of fish compared to control group (P<0.05). Viscerosomatic and hepatosomatic index were affected by both dietary extract levels compared to control group (P<0.05). Dietary plant extract inclusion significantly increased the activity of amylase and lipase (P<0.05). Similarly, the activity of superoxide dismutase and glutathione peroxidase significantly increased in the liver tissue of rainbow trout following feeding on diets containing the extracts, while malondialdehyde content of the tissue decreased in comparison to the control group (P<0.05). Therefore, considering the promising effects of dietary supplementation of turmeric and thyme extracts, inclusion of 0.5% of the extracts in rainbow trout feed is recommended.

This research explored the impacts of feed-born silver nanoparticles (AgNPs) on common carp (Cyprinus carpio) and whether dietary curcumin supplementation could ameliorate the impacts of AgNPs on growth, hemato-biochemical parameters and digestive enzyme activity. Nine experimental diets were prepared containing 0.00, 0.05, and 0.15 g kg-1 AgNPs, as well as 0.00, 0.75, and 1.50 g kg-1 curcumin in a factorial design. Triplicate groups of common carp (4.82 ± 0.41 g) were fed on the test diets for 60 days. The results demonstrated that AgNPs reduced growth performance and enhanced the feed conversion ratio dose-dependently. Supplementing 0.75 g kg-1 curcumin at a low AgNP level improved the growth rate, while its inclusion at a high AgNP level led to further suppression of growth performance. The highest hematocrit value, hemoglobin concentration and white blood cell count were recorded in the group receiving 0.75 g kg-1 curcumin. Serum glucose, cholesterol and triglyceride concentrations were elevated by increasing AgNP levels. However, curcumin inclusion, particularly at the lower level of AgNPs significantly decreased their values. Similarly, intestinal alkaline protease and lipase activities were progressively reduced by increasing dietary AgNP contents, but, significant improvements were observed by curcumin application at the lower AgNP level. Our results revealed that curcumin supplementation could limit the toxic effects of lower dietary AgNP contents.

The present study was carried out with the aim of investigating the effect of a dietary spoiled fish meal along with the protective effects of vitamins E and C on the growth, hematological and biochemical indices of rainbow trout fingerlings. For this purpose, 240 rainbow trout fingerlings with an average weight of 12.75±0.25g were fed on 4 treatments diets including: 1: a diet containing fresh fish meal; treatment 2: a diet with spoiled fish meal; treatment 3: a diet with spoiled fish meal and low level of vitamin supplements (100mg/kg vitamin E, 200mg/kg vitamin C) and treatment 4: a diet containing spoiled fish meal and high levels of vitamin supplements (200mg/kg vitamin E, 400mg/kg vitamin C) for 60 days. At the end of the test period, the indices of final weight, specific growth rate, body weight gain, and food conversion ratio were calculated. Also, hematological parameters, cholesterol, triglyceride, HDL, and LDL were evaluated. Based on the obtained results, the final weight, specific growth rate, and body weight gain decreased in treatments 2, 3, and 4, while the food conversion ratio increased (P≥0.05). WBC and Hb increased in treatments 3 and 4 (P≥0.05). RBC and Htc% augmented in treatment 3 (P≥0.05). Triglyceride diminished in treatments 3 and 4 (P≥0.05), but cholesterol and LDL increased in treatments 2 and 3 and decreased in treatments 2 (P≥0.05). HDL has grown in treatments 3 and 4 (P≥0.05). It can be concluded that spoiled fish meal harms growth, hematological, and biochemical indices, and vitamin supplements are impacts on reducing these effects in hematological and biochemical indices.

This study was carried out with the aim of investigating the effect of diazinon insecticide chronic toxicity as one of the most widely used poisons used in agricultural lands and gardens around Lake Urmia on growth, survival, antioxidant and digestive enzyme activity indices of Artemia urmiana. First, the LC50 of diazinon insecticide for different age stages, including nauplii, post larvae and adults, were measured at 24, 48 and 96 hours using the probit analysis. The LC50 of diazinon for nauplii 23.769, 0.992, 0.008, post larvae 2.231, 0.015, 0.002 and adults 0.919, 0.038, 0.007 (mg/l) were obtained. To investigate the effect of chronic toxicity of diazinon, A. urmiana was cultured in the form of 4 treatments, control, 25% LC50, 50% LC50 and 100% LC50 for 15 days. The growth and survival indices were measured on days 8, 11 and 15, and the activity of antioxidant and digestive enzymes of the biomass were measured at the end of the period. The highest amount of growth and survival was observed in the control treatment and the lowest in the 100% LC50 treatment (P<0.05). The activity of superoxide dismutase decreased in 25% LC50 and 50% LC50 treatments (P<0.05). The activities of catalase and glutathione peroxidase enzymes also decreased in the 25% LC50 and 50% LC50 treatments compared to the 100% LC50 treatment (P>0.05). There was no significant difference between different treatments in the activity of alkaline protease and lipase enzymes (P<0.05). Alpha-amylase enzyme activity decreased with increasing diazinon concentration (P>0.05). In general, it can be concluded that diazinon reduces growth and survival in A. urmiana and has negative effects on enzyme activities. According to the results of the present research, in order to preserve this species, the use of diazinon insecticide in the areas around Lake Urmia should be controlled.

The present study was carried out to investigate the effect of different dietary levels of fermented canola meal by the Bacillus isolated from Caspian Sea sediments on growth and nutritional indices, proximate body composition, and digestive enzymes activity of Nile tilapia fingerlings. A total of 225 fry fish with an average weight of 1.90±0.05 g were fed with five different experimental diets including treatment 1: a diet without fermented canola, treatment 2: a diet containing 12.5% ​fermented canola, treatment 3: a diet containing 25% fermented canola, treatment 4: a diet containing 37.5% fermented canola, and treatment 5: a diet containing 50% fermented canola for 8 weeks. Results revealed that the growth and nutrition indices did not significantly differ among various experimental groups (p>0.05). Proximate analyses of the body composition showed that the protein contents of treatments 2, 3, and 4, the lipid and moisture contents of treatments 3, 4, and 5, and also the ash contents of treatments 4 and 5 were increased compared to the control group (p<0.05). Also, the results of digestive enzymes activity showed that the alkaline protease activity of treatments 3 and 4, lipase activity of treatments 2 and 3 and also the alpha amylase activity of treatment 3 were increased in comparison with the control group (p<0.05). In general, it was concluded that incorporating 50% of fermented canola did not affect growth performance and nutritional indices in Nile tilapia fingerlings.

Regarding the use of cypermethrin insecticide in agriculture in West Azerbaijan and the possibility of its entry into the Urmia Lake, the present study was conducted to investigate the effect of cypermethrin on growth, survival, and some physiological parameters of Artemia urmiana. For this purpose, the LC50 of cypermethrin for 24, 48, and 96 hours in the nauplii, post-larva, and adult stages were obtained using the probit test. The average LC50 of 96 hours was used to study the effect of chronic toxicity. Then, the Naplii was cultured in 4 treatments including the control group, 25% LC50, 50% LC50, and 100% LC50 for 15 days. At the end of the experiment, growth, survival, antioxidant enzymes activity, and digestive enzymes activity of the whole body were evaluated. The results showed that different concentrations of cypermethrin decreased the growth and survival of A. urmiana (p<0.05) and the amount of this decrease depended on the age of Artemia and the exposure duration. The highest decrease in growth and survival of different life stages of A. urmiana was observed in the 100% LC50 group. The results of antioxidant enzymes activity showed that cypermethrin decreased the levels of superoxide dismutase, catalase, and malondialdehyde (p<0.05), but there was no change in the activity of glutathione peroxidase (p>0.05). Also, the activities of lipase and alpha-amylase enzymes were decreased (p<0.05), but no significant difference was observed in the alkaline protease activity (p>0.05). In conclusion, the cypermethrin insecticide decreased the growth, survival, and antioxidant and digestive enzymes activities in A. urmiana.

The present study aimed to evaluate the protective effect of vitamins E and C on reducing the effects of dietary oxidized fish oil on the growth, hematological and biochemical indices of rainbow trout fry. For this purpose, 240 fries with an average weight of 12.75±0.25 g were fed with 4 treatments including, treatment 1: a diet containing fresh fish oil, treatment 2: a diet with oxidized fish oil, treatment 3: a diet containing oxidized fish oil along with the low level of vitamin supplements (100 mg/kg vitamin E, 200 mg/kg vitamin C) and treatment 4: a diet with oxidized fish oil along with the high level of vitamin supplement (200 mg/kg vitamin E, 400 mg/kg vitamin C) for 60 days. At the end of the trial, the indices of specific growth rate (SGR), weight gain percentage (WG), and food conversion ratio (FCR) were calculated. Also, the hematological and serum biochemical parameters: cholesterol, triglyceride, high density lipoprotein (HDL), and low density lipoprotein (LDL) were measured. Based on the obtained results, the SGR and WG, were decreased in 2, 3 and 4 treatments and the FCR was increased (p<0.05). The white blood cells (WBC), red blood cells (RBC), hemoglobin (Hb), and hematocrit (Htc) levels were increased in 2, 3, and 4 treatments (p<0.05). The triglyceride and HDL contents were increased in 3 and 4 treatments, respectively (p<0.05). Also, there were not significant differences between different treatments for serum cholesterol and LDL indices (p>0.05). Finally, it was concluded that oxidized fish oil has adverse effects on growth, hematological and biochemical indices, and the vitamin supplements are effective in reducing these effects on the hematological and biochemical parameters.

In this study, the effects of dietary addition of vitamin C, astaxanthin, and lecithin on the fertility ability (percentage of fertilization and eyed-eggs) and activity of SOD, CAT and GPx in the ovarian fluids of Caspian trout (Salmo caspius) were investigated. For this purpose, nine different experimental diets: C0A0L0 (0 mg kg-1 vitamin C, 0 mg kg-1 astaxanthin and 0% soybean lecithin), C300A50L0, C700A100L0, C0A50L6, C300A100L6, C700A0L6, C0A100L9, C300A0L9, and C700A50L9 were formulated and the broodstocks (2.51±0.05 kg) were fed for four months. After sexual maturation and spawning, the ovarian fluids were isolated to measure the activity of antioxidant enzymes (AAE) and to evaluate its fertilization ability. The sperm mixture of 9 male broodstocks was used to measure fertilization ability. The results showed an increase in the relative fecundity and AAE in ovarian fluid. The lowest relative fecundity (680±38 eggs per Kg of broodstock weight) and SOD, CAT, and GPx (816.33±67.60 u/ml, 1.29±0.40 nmol/min/ml and 1.06±0.08 nmol/min/ml, respectively) were observed in C0A0L0 which significantly different from other treatments (p<0.05). The highest percentage of fertilization and eyed-eggs were obtained in C300A100L6 (91.66±5.13% and 87.63±1.3%, respectively) which significantly different from the freshwater treatment (77.66±4.16% and 47.86±5.1%, respectively; p<0.05). According to the results of this research, adding of 300 mg kg-1 vitamin C with 100 mg kg-1 astaxanthin and 6% lecithin can increase the relative fecundity, fertilization ability and AAE in ovarian fluids of Caspian brown trout.

In this study, the effects of different levels of dietary supplementation with vitamin C, astaxanthin and lecithin on some biochemical indices of ovarian fluid (Total protein, ACP, ALP, LDH and AST enzymes) and reproductive performance (fecundity and fertilization rate) of Caspian brown trout (Salmo trutta caspius) were investigated. For this purpose, nine experimental diets were formulated and supplemented with different combinations of vitamin C at levels of 0, 300 and 700 mg kg-1 diet, astaxanthin at levels of 0, 50 and 100 mg kg-1 diet and soybean lecithin at levels of 0, 6 and 9% (C0A0L0, C300A50L0, C700A100L0, C0A50L6, C300A100L6, C700A0L6, C0A100L9, C300A0L9, C700A50L9) and broodstocks (2.51±0.05 kg) were fed for four months. After maturation and stripping, ovarian fluid was separated for biochemical indices and oocytes used for reproductive performance. Based on the results, a significantly increase was observed in the total protein content of ovarian fluid of fish fed with the treatments C300A100L6, C700A50L9, C700A0L6, C0A100L9 and  C300A0L9 compared to the control (p<0.05). Also, the lowest LDH ​​were obtained in treatments C300A100L6, C0A100L9 and C0A50L6, which were significantly different from the control (p<0.05). Treatments C700A0L6 and C0A100L9 had the lowest AST ​​and the highest ALP values, both of which were significantly different from the control (p<0.05). The highest fecundity and fertilization rate were observed in C0A100L9 and C300A100L6 treatments which were significantly different from the control (p<0.05). In conclusion, dietary supplementation of 300 mg kg-1 vitamin C with 100 mg kg-1 astaxanthin and 6% lecithin led to a decrease in AST and LDH enzymes activity and improvement of fecundity and fertilization rates.

In this study, the effects of different levels of dietary supplementation with vitamin C, astaxanthin and lecithin on ionic (K+, Na+, Ca2+ and Mg2+) and biochemical (Total protein, cholesterol and glucose) indices of ovarian fluid, also its effect on sperm motility duration in Caspian brown trout (Salmo trutta caspius) were investigated. For this purpose, nine experimental diets: C0A0L0 (0 mg kg-1 vitamin C, 0 mg kg-1 astaxanthin and 0% soybean lecithin), C300A50L0, C700A100L0, C0A50L6, C300A100L6, C700A0L6, C0A100L9, C300A0L9 and C700A50L9 were formulated and broodstocks (2.51±0.05 kg) were fed for four months. After maturation and stripping, ovarian fluid was separated for ionic and biochemical indices. To evaluate sperm motility, 1 μl of milt was placed under a microscope with fresh water (as a control treatment) or ovarian fluid of experimental fishes. Sperm motility was measured with a chronometer. Results showed that the highest amounts of Na+, K+, Ca2+ and Mg2+ ions were obtained in ovarian fluid of C300A100L6, C300A100L6, C0A100L9 and C300A100L6, respectively, which were significantly different from C700A50L9 (p<0.05). Also, the highest levels of protein, cholesterol and glucose were observed in C700A50L9, C0A50L6 and C0A100L9 treatments, which were significantly different from C0A0L0 treatment (p<0.05). Lowest duration of sperm motility was obtained in fresh water (43.96±2.25 seconds) which was significantly different from other treatments (p<0.05); however, the highest sperm motility was observed in C300A100L6 and C0A100L9 treatments (80.76±2.03 and 80.7±1.76 seconds, respectively).

The present study was aimed to determine the intestinal histopathological changes of common carp fingerling following dietary exposure to Roundup® and the efficacy of dietary inclusion of medicinal plants thyme and rosemary powders to decrease such tissue changes. For this purpose, 300 fingerlings with an average body weight of 15±1.5g were randomly distributed to 5 treatments and fed at 3 different stages as follow: stage 1 with a diet containing 20g/kg of plant powder alone or in combination (treatments 3-5), stage 2 with a diet containing 2.3 mg/kg of Roundup® (treatments 2-5) and stage 3 feeding with diets with neither contaminant nor the medicinal plant powders. Results showed that at the end of the first stage, intestinal tissue had normal microscopic appearance. Pathological changes including necrosis, detachment of intestinal villus, vacuolation in intestinal epithelial cells, infiltration of inflammatory cells along with edema and hyperemia were observed at the end of the second stage in those groups exposed to dietary Roundup® (treatment 2), but those fish previously received diets supplemented with rosemary or thyme (treatments 3 and 4) showed mild tissue changes. Furthermore, simultaneous dietary administration of rosemary and thyme powders (treatment 5) resulted in better tissue protection. Based on the results of the stage 3, after two weeks long recovery period, tissue significant structure amendment was observed in comparison to the previous stage (P<0.05). In conclusion, dietary inclusion of medicinal plant Rosmarinus officinalis and Zataria multiflora powders could reduce the histopathological changes in intestine of common carp fingerling exposed to dietary Roundup®.

In the present study, the effects of different levels of dietary antioxidant supplements on growth performance and biochemical indices in rainbow trout (Oncorhynchus mykiss) fingerlings were investigated. For this aim, nine experimental diets were formulated and supplemented with different combinations of three antioxidants including vitamin E (VE) at levels of 0, 100 and 150 mg kg-1 diet), coenzyme Q10 (CoQ10) at levels of 0, 10 and 20 mg kg-1 diet and selenium forms (mineral, organic and nano-selenium (Nano-Se)) at levels of 0, 0.3 and 0.5 mg kg-1 diet. The fish were randomly divided into these diets with stocking density of 25 per replicate and fed for 56 days. Based on the results, a relative increase was observed in the growth indices of fish fed with the treatment containing 0.5 mg Nano-Se + 100 mg VE. The highest of glucose content was obtained in supplemented treatment with 0.5 mg Nano-Se + 100 mg VE. For cholesterol and triglyceride, the highest values were reported in fish fed with treatments containing 0.5 mg mineral Se + 150 mg VE + 20 mg CoQ10 and 0.5 mg Nano-Se + 100 mg VE, respectively. Similarly, the highest values ​​of HDL and VLDL indices were observed fish fed with 0.5 mg Nano-Se + 100 mg VE. In contrast, the control treatment showed the highest LDL value. The results of this study revealed that supplemented diet with Nano-Se at level of 0.5 mg and VE at level of 100 mg can be effective in improving the growth and blood biochemical indices of rainbow trout.

Considering the role of conjugated linoleic acid (CLA) and soybean lecithin (SBL) in fat digestion, absorption and metabolism as well as stress resistance in aquatic organisms, the current study was a 74-day attempt to investigate the synergistic effects of these two compounds on stress resistance and blood lipoprotein levels of rainbow trout (Oncorhynchus mykiss) weighing 120±5 g. Nine isonitrogenous and isocaloric experimental diets containing 1, 2 and 3% CLA and 2, 3 and 4% soybean lecithin on the basis of the basal control diet (free from CLA and lecithin) were formulated. The fish were exposed to three ascending periods of hypoxic stress (7.5, 15 and 30 min) at the end of culture period. The dissolved oxygen was decreased to 1.96 ppm by injecting nitrogen gas. Significantly higher levels of cortisol and glucose were detected in fish fed on diets having higher levels of SBL (2%) and CLA (3%) at higher stress time improving the resistance to hypoxia stress (P≤0.05). Moreover, levels of triglyceride (TRG), cholesterol (COL), low density lipoprotein (LDL), very low-density lipoprotein (VLDL) and high density lipoprotein (HDL) also increased significantly compared to the control group (P≤0.05). This study reveals that using 2% SBL and 3% CLA in rainbow trout feed can promote resistance to hypoxic stress.

The purpose of this study is to investigate the effects of aflatoxin B1 and zearalenone in regards to changes in growth indices and body composition of gold fish. For this purpose, 675 juvenile fish weighing approximately 6.25±0.12 grams in the form of 9 experimental treatments with diets containing three levels of Aflatoxin B1 (AF) (0, 50 and 100 ppb) and three levels of Zearalenone (ZER) (0, 500 and 1000 ppb) and they were fed for 60 days. Then, growth indices and body composition were measured. Based on the results, the weight gain in juveniles fed diets containing AF50 with ZER1000 andAF100ZER1000 (treatments 7 and 9) decreased compared to the control group (p<0.05). Groups fed with diet containing AF50, AF100ZER500, and AF100ZER1000 showed lower weight gain (p<0.05). Specific growth rate at levels of AF50, AF100, ZER1000 and combination treatments of two toxins had a significant decrease compared to the control group (p <0.05). Although there was no significant difference between treatments in indices of feed conversion ratio, the lowest value was observed in the group without toxin (treatment 1) and the highest value was observed in treatment 9 (AF100ZER1000) (p >0.05). The lowest body protein was observed in treatment 6 (AF50ZER500) (p <0.05). Also, the lowest body fat was observed in treatment 4 (ZER500) (p <0.05). The lowest moisture was observed in treatment 7 (AF50ZER1000) (p <0.05). It can be concluded that both Aflatoxin B1 and Zearalenone alone, reduce growth indices and changes in body composition, but the simultaneous presence of two toxins has the greatest effect on these indices.

The aim of this study was to evaluate the histological effects of aflatoxin B1 (AFB1) and zearalenone (ZEA) on the liver tissue of the rainbow trout. In this study, 540 rainbow trout 12.07±0.23 g (Mean±SD), as 9 experimental treatments with three replications were fed separately and simultaneously with diets containing different concentrations of AFB1 and ZEA over 60 days. In this regard, the concentrations of 50 and 100 ppb AFB1 and 300 and 600 ppb of ZEA were used. At the end of the experimental period, the liver tissue was sampled and pathological changes were qualitatively and semi-quantitatively examined. The toxin-induced histological damage included necrosis and deformation of hepatocytes. The severity of tissue lesions increased with increasing dietary levels of AFB1 and ZEA separately and simultaneously. The results showed that the severity of lesions was higher in fish receiving diets containing combinations of AFB1 and ZEA in comparison to other treatments.

Present study was carried out to assess effects of aflatoxin B1 on different rainbow trout tissues. In the present study, 207 rainbow trout fingerlings with an average body weight of 9.67±0.2 g were reared for eight weeks in three distinctive treatments (control group, 25 and 50 ppb aflatoxin B1). At the end of the trial, various tissues of experimental groups were studied regarding probable histological alterations. Histological alterations due to dietary aflatoxin B1 exposure including hyperplasia and lamellar necrosis in the gill, necrotic and vascular changes in the brain along with inflammatory cell infiltration and necrotic changes in the intestinal and pyloric region were evident. The severity of pathologies was more pronounced in those fish received 50 ppb aflatoxin B1 content in comparison to the group fed 25 ppb toxin contaminated diet.

The effect of stocking density and dietary aflatoxin B1 along with rosemary and thyme powders on intestinal digestive enzymes activity of rainbow trout was evaluated. Total of 600 fish with an average weight of 90±3 were randomly allotted among six experimental groups consisted of two stocking density (15 and 45 kg.m-3), aflatoxin contamination (0 and 50 ppb) with/without including 4 % herbal blend powder (2% rosemary and 2% thyme). Each treatment was replicated thrice and the experiment was lasted for 6 weeks. Stocking at high density and receiving aflatoxin B1 contaminated diet resulted in higher digestive enzymes activity including amylase, lipase and alkaline protease (p≤0.05). It seemed that including herbal blend consisting of rosemary and thyme powder could mitigate pathologically elevated digestive enzymes activity due to dietary aflatoxin contamination (p≤0.05). In conclusion, dietary inclusion of rosemary and thyme multi-blend in aflatoxin contaminated diets at the studied level could ameliorate undesirable effects of aflatoxin on intestinal digestive enzymes activity of rainbow trout reared at various densities.

Nowadays, the aquaculture industry is challenged with dietary mycotoxin contamination and their undesirable effects on fish. It is believed that feed containing antioxidants might be useful to modulate or even eradicate such problems. This study was to investigate the protective role of thyme and rosemary powder in the diet to reduce the toxic effects of dietary aflatoxin B1 and zearalenone contamination on some immune indices of rainbow trout fingerlings. Total number of 180 fish (3±0.2g) were allotted into three treatments including treatment one as control group (without toxin), treatment two received feed containing 50µg/kg aflatoxin B1 + 400µg/kg zearalenone and treatment three fed diet contaminated with 50µg/kg aflatoxin B1 + 400µg/kg zearalenone and contained 2% rosemary and 2% thyme powder (triplicate) for 4 weeks. The results showed that lysozyme and complement activity, serum total antibody content along with red and white blood cell counts were not affected by experimental diets (P>0.05). While lymphocyte proliferation and neutrophils phagocytosis indices and lymphocyte to neutrophil ratio were affected by treatments (P<0.05), as the lowest and the highest level of these indices, belonged to treatments two and three, respectively (P<0.05). The results showed that adding rosemary and thyme powder to mycotoxin contaminated diet could improve immune parameters of rainbow trout especially lymphocyte proliferation and lymphocyte to neutrophil ratio.

The present study was to investigate the effect of dietary conjugated linoleic acid (CLA) at various inclusion levels of lecithin on immune indices of rainbow trout. To do so, 600 rainbow trout with an average body weight of 100±10g were randomly allotted into 10 distinct treatments comprised of various combinations of three dietary inclusion levels of lecithin (2, 3 and 4%) and CLA (1, 2 and 3%) along with a control group (devoid of CLA and lecithin) for 70 days. At the end of the experiment, immune parameters including lysozyme activity, complementary pathway, total antibody, lymphocyte proliferation and phagocytic power of the neutrophil (NR assay) were assayed. Lysozyme activity, complement pathway and total antibody content of serum of those fish fed diet containing 4% lecithin were affected by dietary CLA level to extent that lysozyme activity was the highest at 1% of CLA, while complement pathway and total antibody content of serum were the highest in diets containing 2% CLA (P<0.05). Lymphocyte proliferation of those fish fed diet containing at least 3% lecithin along with 2% CLA was the highest (P<0.05), and NR was significantly increased in those fish received diet included with at least 2% lecithin and 1% CLA (P<0.05). In conclusion, dietary incorporation of at least 1% CLA along with 3% lecithin could improve immune parameters of rainbow trout.

The present study was to investigate the effect of various dietary levels of unsaturated fatty acids (HUFA and PUFA) on some morphometric features of duodenum in newly weaned rainbow trout larvae. Therefore, eight different experimental diets consisted of various dietary levels of HUFA (0, 0.5, 1 and 2 percent) at a fixed dietary PUFA of 20 percent (the first experiment) and various dietary PUFA levels (10, 20, 30 and 40 percent) at a fixed dietary HUFA of 8 percent (the second experiment) were formulated. Stocking density of larvae was 100 larvae per each container and the experiments lasted for six weeks. At the end of the experiments, six fish were randomly taken and the proximal intestine was dissected out and fixed for classical histological studies. In the first experiment concomitant with any increase in dietary HUFA content, epithelial thickness and villous height significantly decreased (P<0.05) and according to the results the appropriate HUFA level could be 0.5 percent of the dietary lipid moiety. However, in the second experiment only villous height of duodenum was affected by experimental diets (P<0.05) and villous height was the highest (207.2±10.3μm) at PUFA level of 20 percent of the total dietary lipid. In conclusion, it is recommended that in the case of using vegetable oils in feed formulation (to replace marine lipid sources) led to higher PUFA levels, dietary HUFA levels could be increased to eight percent for keeping normal intestine morphometry.

In the present study, the effects of enrichment of Artemia franciscana with fish oil and soybean oil accompanied with vitamin E were investigated on the structure of pyloric caeca in Persian sturgeon (Acipenser persicus) larvae. A total of 1500 Persian sturgeon larvae (with the average weight of 51±2 mg) were divided into 15 tanks. Larvae were fed for 17 days in 5 experimental treatments including the treatment C (non-enriched artemia), S15 (enriched artemia with soybean oil and 15% vitamin E), S30 (enriched artemia with soybean oil and 30% vitamin E), F15 (enriched artemia with fish oil and 15% vitamin E) and F30 (enriched artemia with fish oil and 30% vitamin E). From each traetment, 15 larvae were collected and were fixed in Bouin’s solution for histological studies. Histological results showed that both fish oil and soybean oil were the main and effective factors on the total area and histo area indices of the pyloric caeca and the enrichment of artemia with fish oil and soybean oil was significantly increased this factor as compared to that of the control treatment (P

Nowadays, mitigating the effects of mycotoxins is an important issue in aquafeed industry. In the present study, 135 common carp fingerlings with an average body weight of 15±1.5 g were reared for 12 weeks in three distinctive treatments (control group, 400 ppb aflatoxin B1 and 400 ppb aflatoxin B1 400 ppb along with rosemary and thyme powder). At the end of the trial, hepatopancreas, intestine and blood samples were taken for determination of alkaline protease, lipase and amylase activities and some blood indices. Results revealed that diets contaminated with aflatoxin B1 and the diet supplemented with rosemary and thyme for 12 weeks did significantly affect alkaline protease activity of hepatopancreas and intestine activity, RBC count, hemoglobin, neutrophil and lymphocyte (P≥0.05), however, did not significantly affect intestinal lipase and hepatopancreatic amylase activity along with other hematological indices (P<0.05). The highest intestinal alkaline protease and amylase activity were observed in fish fed diet containing 400 ppb aflatoxin. In addition, the lowest hepatopancreatic and intestinal alkaline protease, lipase and amylase activities belonged to those fish received aflatoxin contaminated diet supplemented with rosemary and thyme (P<0.05). It could be concluded that including rosemary and thyme in diet contaminated with aflatoxin B1 could mitigate the deteriorative effect of the mycotoxin on intestinal alkaline protease and amylase activities along with RBC count, hemoglobin content, neutrophil and lymphocytes of common carp fingerlings.