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11.
Rainbow trout (Oncorhynchus mykiss) was reared under low (LD) and high (HD) stocking densities for 70 days, during which they were fed with diets supplemented with 0, 5 and 10 g tryptophan (Trp) per kg. At the end of the experiment, there were significant interaction effects of the stocking density and Trp levels on plasma Trp, globulin, lysozyme, catalase (CAT), malondialdehyde (MDA), and bactericidal activity and blood leucocyte count. However, there was no difference in plasma complement (ACH50), total immunoglobulin (Ig), total antioxidant capacity (TAC), superoxide dismutase (SOD) and blood differential leucocyte count. Trp at 5 g per kg diet significantly increased lysozyme and bactericidal activity, and decreased MDA under both the LD and HD conditions. Moreover, it significantly increased plasma CAT and blood leucocyte under the LD and HD conditions respectively. Trp at 10 g per kg diet significantly increased blood leucocyte and plasma bactericidal activity under the LD condition, but significantly decreased plasma globulin and bactericidal activity under the HD condition. In conclusion, the present results showed that the effects of Trp on immune and antioxidant systems depend on Trp levels and stressful conditions. As 5 g Trp per kg diet is beneficial for rainbow trout well‐being under both the LD and HD conditions, higher level of Trp (10 g/kg) is not beneficial and even causes some negative effects under the HD condition.  相似文献   
12.
In the present study, potential ameliorative effects of dietary ginger (GN) were investigated on antioxidant and immune responses of rainbow trout (Oncorhynchus mykiss) during oxytetracycline (OX) administration. As a 2 × 3 factorial design, the fish were orally treated with OX (a daily dose of 100 mg/kg) and GN (either 10 or 20 g/kg diet) for 10 days. Then, blood samples were taken from each treatment to monitor plasma lysozyme, complement (ACH50), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione‐S‐transferase (GST) activities, and reduced glutathione (GSH), malondialdehyde (MDA), total immunoglobulin (Ig) and globulin levels. OX treatment significantly decreased SOD (30%), GPx, (10%) and lysozyme (23%) activities, and GSH (19%) levels; however, it increased GST (16%) activity and MDA (28%) levels. Ten grams GN per kg levels significantly decreased SOD (35%), CAT (13%), GST (20%) and MDA (30%), but increased GSH (30%), lysozyme (48%) and globulin (16%). Twenty grams GN per kg diet significantly decreased SOD (26%) and MDA (17%), but increased lysozyme (31%) levels. Interaction effects of dietary GN and OX were observed on plasma MDA and GPx levels, as 10 g GN per kg diet prevented the OTC‐induced changes in these parameters. Moreover, 20 g GN per kg diet prevented the OX‐induced change in GPx activity and mitigated the MDA elevation by 20%. It is concluded that GN administration at 10 g/kg diet is beneficial in mitigating oxidative stress and immunosuppression of rainbow trout during OX administration.  相似文献   
13.
The aim of the present study was to investigate anesthetic efficacy of myrcene in rainbow trout (Oncorhynchus mykiss) along with the fish biochemical response to anesthesia in comparison with eugenol. In the first experiment, 240 fish were stocked in 12 tanks and acclimatized to experimental conditions for 2 weeks. Then, the fish of each tank were subjected to one concentration of either eugenol (12, 20, 30, 50, 80, and 130 μL/L) or myrcene (100, 150, 200, 300, 400, and 500 μL/L) concentrations. Induction time of and recovery time from anesthesia were recorded for each fish separately. Using these results, desired concentrations to induce anesthesia within 60, 180, 300, and 600 s were determined, being 81, 30, 19, and 10 μL/L eugenol and 531, 251, 177, and 111 μL/L myrcene. In the second experiment, 96 fish were stocked in 8 tanks. Six fish were netted from each tank and exposed to the calculated eugenol or myrcene concentrations. Blood samples were taken after the fish reached anesthesia. The results showed that there was no significant difference in serum lactate, alanine transaminase, and alkaline phosphatase. Increase in the induction time of anesthesia resulted in increased serum glucose with no significant difference between the anesthetics. Increase in induction time of anesthesia led to increase in serum lactate dehydrogenase activity in the eugenol-anesthetized fish and aspartate transaminase activity in myrcene-anesthetized fish. In conclusion, myrcene is capable to anesthetize rainbow trout, but at higher concentrations compared to eugenol. In addition, biochemical analysis showed that increase in induction time of anesthesia leads to hyperglycemia and increase in AST and LDH activities depending on anesthetic type.  相似文献   
14.
As amino acids (AAs) are vital molecules in the metabolism of all living organisms and are the building blocks of enzymes, a 6-week feeding trial was conducted for determining the influence of dietary essential amino acid (EAA) deficiencies on pancreatic, plasma, and hepatic enzyme activities in silvery-black porgy (initial weight 4.7?±?0.01 g) juveniles. Eleven isoproteic (ca. 47%) and isoenergetic (ca. 20.5 MJ kg?1) diets were formulated including a control diet, in which 60% of dietary nitrogen were provided by intact protein (fish meal, gelatin, and wheat meal) and 40% by crystalline AA. The other 10 diets were formulated by 40% reduction in each EAA from the control diet. At the end of the experiment, fish fed with threonine-deficient diet showed the lowest survival rate (P?<?0.05), whereas growth performance decreased in fish fed all EAA-deficient diets, although the reduction in body growth varied depending on the EAA considered. Pancreatic enzymes (trypsin, lipase, α-amylase, and carboxypeptidase A) activities significantly decreased in fish fed the EAA-deficient diets in comparison with fish fed the control diet (P?<?0.05). Fish fed with the arginine-deficient diet had the highest plasma and liver alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase levels (P?<?0.05). Plasma and liver lactate dehydrogenase and superoxide dismutase showed the highest and lowest values, respectively, in fish fed the arginine and lysine-deficient diets (P?<?0.05). Plasma metabolites were significantly affected by dietary EAA deficiencies (P?<?0.05). The results of this study suggesting dietary EAA deficiencies led to reduction in growth performance as well as pancreatic and liver malfunction. Furthermore, arginine and lysine are the most limited EAA for digestive enzyme activities and liver health in silvery-black porgy.  相似文献   
15.
International Aquatic Research - A 6-week feeding trial was conducted to evaluate the effects of protein-free (PF) and essential amino-acid-deficient (EAAD) diets on the growth performance and...  相似文献   
16.
17.

Background:

The variable numbers of tandem-repeat (VNTR) alleles at the phenylalanine hydroxylase (PAH) gene have been used in carrier detection and prenatal diagnosis in phenylketonuria families. This study was carried out to analyze VNTR alleles at the PAH gene in Iranian Azeri Turkish population.

Methods:

In this study, 200 alleles from general population were studied by PCR.

Results:

The frequencies of VNTR alleles were 45%, 46%, 2%, 3%, 1%, and 3% in studied group regarding 3, 8, 9, 11, 12, and 13 repeat copies, respectively. Statistically significant differences were not found between expected and observed frequencies of VNTR genotypes (P > 0.05).

Conclusions:

VNTR alleles with three and eight repeats were frequent, and the VNTR alleles with 13 repeats showed 3% frequency in the tested group. This study is the first report on tested population genetic structure using VNTR alleles at the PAH gene. Key Words: Phenylalanine hydroxylase, Population genetics, Variable numbers of tandem-repeat  相似文献   
18.
ABSTRACT

Caspian roach (Rutilus rutilus caspicus) were exposed to 0, 30, 40, 45, 50, 55, 60, 70, 100, 150 200, 250, 300, and 400 ppm formalin to determine LC50. Respectively, 0.5 to 96 h LC50 values were 252 to 49 ppm. The lowest observed effect concentrations (LOEC) and no observed effect concentrations (NOEC) varied between 40 to 150 and 30 to 100 ppm, respectively, across the tested time spectrum. Regression suggested that the concentrations of 88.4, 80.3, 51.2, and 40.1 ppm are maximum concentrations for 0.5, 1, 12, and 24 h bath treatment, respectively, which are not in the range suggested in the literature.  相似文献   
19.
Effect of dietary tryptophan (TRP) on copper toxicity was investigated in common carp, Cyprinus carpio. Fish were randomly distributed into two triplicate treatments (control and TRP) and fed control (TRP?=?3.1?g?kg(-1)) or TRP (TRP?=?8.1?g?kg(-1)) diets over a 2-week period. Then, both treatments were subjected to 10?mg?l(-1) copper sulfate over a 7-day period. Mortality and serum cortisol, glucose, alanine aminotransferase (ALT), aspartate aminotransferase (AST), sodium, potassium, and chloride levels were recorded at 0, 24, 72, 120, and 168?h post-copper exposure. There was no mortality in the TRP group, whereas the control group mortality was started at 120?h post-copper exposure (21.7?±?7.6?%) and reached 61.7?±?10.4?% at the end of the experiment. Cortisol, glucose, ALT, and AST levels significantly (P?相似文献   
20.
Anaesthetic efficacy of eugenol was investigated on iridescent shark, Pangasius hypophthalmus. Fish (2, 5, 10 and 20 g) subjected to 20–200 mg L?1 eugenol and behavioural response as well as induction and recovery times were recorded. Induction and recovery times were significantly affected by eugenol concentration as well as fish weight (< 0.05). Generally, 27–300 s after exposure to 20–200 mg L?1 eugenol, iridescent sharks reached stage 3 anaesthesia (suitable for general handling). Fish entered stage 4 anaesthesia (suitable for surgery and blood sampling) over 54–710 s exposure to such concentrations. Recovery time was 109–600 s in all weight classes as well as eugenol concentrations. Mortality (44–100%) was only observed in 2 g fish when subjected to 110–170 mg L?1 eugenol. This study, for the first time, showed behavioural response of iridescent shark to anaesthesia as well as effectiveness of eugenol as anaesthetic in this important aquaculture‐ornamental species. According to the models obtained in this study, minimum eugenol concentrations to induce anaesthesia over less than 3 min were 53.8–81.5 mg L?1 in 2–20 g fish. Likewise, maximum eugenol concentrations in which fish recovered over less than 5 min were 65.9–105.8 mg L?1 in 2–20 g fish.  相似文献   
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