Showing 8 results for Cortisol
, ,
Volume 3, Issue 4 (2-2015)
Abstract
The effects of stress on body cortisol and reproductive performance of guppy, Poeciliar eticulata, was evaluated on 90 immature female fish (0.29 ± 0.03g body weight). The experiment, carried for 30 days in three replications, included: the control (without any manipulation), handling stress (daily holding in a net for 2 minutes) and feeding with the cortisol-treated diet (500 mg per kg food). After this period, reproduction was induced by adding male fish to the remaining females in each tank. No significant difference was observed in growth rate among the treatments (p=0.001). The mortality rate and body cortisol content in both handling and cortisol-fed treatments were significantly higher than that in the control group (p=0.000). The minimum and maximum number of embryos was observed in the control and cortisol-fed groups, respectively. Our results indicated that such manipulations have negative effects on survival and reproductive efficiency and change whole-body cortisol content. Therefore, the measurement of whole-body cortisol content could be a suitable criterion for determining physiological condition in small laboratory fishes.
Mahtab Yarmohammadi, Mohammad , , , ,
Volume 4, Issue 4 (3-2016)
Abstract
The effects of starvation periods on physiological response of the juvenile Persian sturgeon, Acipencer persicus, was assessed through such stress factors as glucose, cortisol and hepatic enzymes for a period of 8 weeks. For this purpose, in a randomly designed experiment, five groups of fish (108.04 ± 0.28 gr) in 3 replicates were starved for a period of 0 (control), 1, 2, 3 and 4 weeks and fed them to satiation after their starvation lags. Blood plasma glucose and cortisol during starvation periods did not significantly change (p>0.05). This indicates high performance of this specific in maintenance of blood glucose during starvation and recovery of glucose level after feeding. However, plasma hepatic enzymes level in fasting treatments increased (p<0.05), but reached the control level after 4 weeks of feeding. Considering the role of liver enzymes in gluconeogenesis and taking into consideration the constant plasma glucose and cortisol during periods of food deprivation, it seems that liver enzymes in the Persian sturgeon during food deprivation play a key role in stabilizing blood glucose.
Considering the role of liver enzymes in gluconeogenesis, and taking into consideration the constant plasma glucose and cortisol during periods of food deprivation, In this study, it seems that liver enzymes in the Persian sturgeon during food deprivation play a key role in stabilizing blood glucose.
, Mahmoud Nafisi Bahabadi, , , ,
Volume 5, Issue 2 (9-2016)
Abstract
In the current study, the effect of fresh water and different salinities of 15, 35 and 50 ppt on growth, feeding, body composition, glucose and cortisol in Asian sea bass (Lates calcarifer); were investigated. 180 fingerlings with average weight of 34.36±0.41 gram in 12 circular fiberglass tanks with 300 liter volumes were administered. Feedinng was done to satiation twice a day for 30 days. At the end of the experiment, biometry carried out and plasma and carcass samples were collected for estimating blood biochemical parameters and whole body composition. The obtained results showed that freshwater treatment had a significant difference in growth and feeding performance with other treatments (p < 0.05). Also, the results of carcass analyze showed that freshwater treatment moisture percentage was significantly higher (72.07±0.11) compared to other treatments (p < 0.05). Glucose and cortisol value in 15 ppt treatment were significantly higher at 35, 50 ppt treatment and 35 ppt, freshwater treatment, respectively (p < 0.05). Overall, this study showed this species is able to tolerate changes in salinity in the surrounding medium from seawater to brackish water through a period of 30 days and successfully adapt to freshwater without showing mortality. But, it could not be a good case for culture in fresh water because of using high energy for osmoregulation in fresh water.
Sh. Masoudi Asil , A.m. Abedian Kenari , Ghodrat Rahimi Mianji, G. van der Kraak,
Volume 7, Issue 2 (6-2018)
Abstract
Aims: Arachidonic acid is an essential fatty acid that plays an important role in the fish reproduction process by regulating the function of the intravenous system, including the synthesis of steroid hormones. The aim of this study was to evaluate the effect of different levels of dietary arachidonic acid on calcium, thyroid hormone, and cortisol levels in vitellogenesis and maturation stages of female blue gourami (Trichopodus trichopterus).
Materials and Methods: In this applied research, 150 one-month blue gourami were distributed among 15 aquariums (3 replicates for each treatment) and fed with 5 different dietary ARA levels (0.02, 0.53, 1.05, 1.6 and 2.12% of diet) until the completion of maturation over 5 months. After they reached sexual maturity, 12 females from each treatment were selected; calcium level in plasma, cortisol concentrations in serum, and thyroid hormones, triiodothyronine (T3) and thyroxine (T4), were measured in ovary in both vitellogenesis and maturation stages by photometry and ELISA methods, respectively. The data were analyzed by one-way ANOVA after Kolmogorov-Smirnov test. Duncan’s multiple range test was used at 5% level for a meaningful comparison between the means. Pearson correlation coefficient was used to calculate the relationship between arachidonic levels of diet and the measured parameters. All analyses were performed by SPSS 22 software.
Findings: In the vitellogenesis stage, in the treatments with high arachidonic levels, calcium ion had the highest and cortisol hormone had the lowest levels (p<0.05). The level of cortisol in the maturation stage was higher than that of the vitellogenesis and also increased with increasing arachidonic levels. The level of T3 in the ovaries of fish in both stages of vitellogenesis and maturation increased significantly with increasing ARA levels (p<0.05). The level of T4 in the ovaries of the fish did not have a significant relationship with the increase in ARA levels in the vitellogenesis stage, while in the maturation stage, with increasing ARA, the amount of storage of this hormone significantly increased (p<0.05).
Conclusion: Using high levels of arachidonic in the reproduction stage can increase the level of calcium and thyroid hormones and, as a result, improve the vitellogenesis. In the maturation stage, increasing arachidonic levels up to 1.6% increases the levels of cortisol.
Majid Mohammad Nejad,
Volume 10, Issue 3 (9-2021)
Abstract
Aims Hematological and biochemical parameters are valuable indicators for monitoring fish health and physiological responses, nutritional status and environmental conditions affecting fish health. In this study, the comparison of hematological indices and some biochemical and hormonal factors of blood serum in male and female sea carp were investigated.
Materials and Methods For this purpose, blood samples were taken from two groups of male and female broodstock with 14 fish from each group.
Findings The results of this study on hematological factors showed that in terms of red blood cell (RBC), hematocrit (HCT), hemoglobin (HB), mean red blood cell volume (MCV), mean concentration of hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), white blood cell (WBC), monocyte (Mo) and granulocyte (Gr), there is no statistically significant difference between the two sexes (P> 0.05). The results of this study showed that there was a statistically significant difference between males and females in terms of glucose, cholesterol, calcium and cortisol (P <0.05). The amount of glucose and cholesterol in males and the amount of calcium and cortisol in females were higher. There is no statistically significant difference between males and females in terms of triglyceride, total protein, albumin, sodium and potassium (P> 0.05).
Conclusion The results of this study show that sex in sea carp during maturity has no effect on the hematological parameters of fish but can affect some biochemical factors in the blood serum of carp such as glucose, cholesterol, calcium and cortisol.
Fahimeh Tollabian, Morteza Kamali,
Volume 11, Issue 1 (3-2022)
Abstract
The present study was designed to evaluate the effect of acetaminophen on hematologic and blood biochemistry of rainbow trout in a 4-day period. To that end, total 300 fingerlings with an average body weight of 12.5±2.5 g were randomly allocated into 15 polyethylene tanks (with 100L volume). Fingerlings were exposed to five concentrations of acetaminophen, namely, 0, 0.01, 0.1, 1. 10 mg/L for 4 days. Hematologic and Biochemical Parameters of Rainbow Trout (Oncorhynchus mykiss) exposed to Acetaminophen were measured. According to the results, the number of white blood cells was significantly different compared to the control group and other treatments at concentration of 10 mg/l. The number of red blood cells, hemoglobin, mean hemoglobin volume (MCV) and hematocrit were higher in the control group and And the lowest amount was observed at a concentration of 10 mg/l and There was a significant difference between these parameters in different treatments. There wasn´t significant difference in mean corpuscular hemoglobin concentration (MCH) between experimental treatments. There was a significant difference in serum lysozyme enzyme and complement (ACH50) activity in fingerling exposed to acetaminophen. There was a significant difference in cortisol and glucose levels in different treatments so that the most amount of cortisol and glucose showed in the control group and the less amount was observed in treatment 5.
Volume 15, Issue 2 (3-2013)
Abstract
The aim of this study was to analyze the stress response during 3 hours net confinement stress and recovery period of 22 hours in normal (STD) and in 17α-hydroxylase deficient common carp (E5). Fish were raised for 6 months and sampled at T0 (control, unstressed), 5 minutes, 20 minutes, 1 hour and 3 hours of exposure to net confinement, and after 1 hour, 4 hours, and 22 hours of recovery. At every sampling time, blood was collected to determine cortisol, corticosterone, glucose, lactate and free fatty acids (FFA) levels (5 fish per strain). Fish and head kidney were weighed before and after dissection, respectively, to determine head kidney somatic Index (HKSI). Morphometric analysis of head kidney tissues indicated that the head kidney somatic index was significantly higher in E5 fish (0.076±0.021) compared with STD fish (0.045±0.015). Also, significant differences in cortisol and corticosterone as well as in glucose, lactate and FFA values were observed between the two strains of E5 and STD. Moreover, the pattern of changes of glucose and FFA during stress and afterward indicated a significant difference compared to the T0. Results support the conclusion that the reduced capacity of ill fish to produce cortisol is caused by a deficiency in 17α-hydroxylase activity. A reduced cortisol output leads to increased stimulation of adrenals by adrenocorticotropic Hormone (ACTH), resulting in increased outputs of corticosterone.
Volume 17, Issue 5 (9-2015)
Abstract
The effects of dietary nucleotide (NT) were evaluated on some serum biochemical parameters and acute stress responses of the catfish (Pangasianodon hypophthalmus). Five experimental diets including 0, 0.25, 0.5, 0.75, and 1% NT were supplied to catfish fry for 10 weeks. At the end of the experiment, fish fed the control and 1% NT diets were subjected to handling and crowding stress. The results showed that the fish supplied with 0.25-0.75% NT had a lower level of lactate dehydrogenase (LDH) (P<0.05) while other serum enzymes including alkaline phosphatase (ALP), asparate transaminase (ASP), and alanine transaminase (ALT) were not significantly reduced by NT inclusion in the diet (P>0.05). The fish which received the highest doses (0.75 and 1%) of NT exhibited higher levels of triglyceride than the other groups (P<0.05) while they showed no significant differences in other biochemical parameters including total protein, albumin, globulin, cholesterol, and glucose (P>0.05). To investigate stress responses, cortisol (primary response), serum glucose, and serum ion concentrations including sodium, potassium and calcium (secondary responses) were measured. The results showed significant fluctuations in all the tested components during the sampling intervals for up to 48 h post-stress; the exceptions, however, were glucose in the group on the 1% NT diet as well as serum cortisol and calcium levels in those supplied with the control diet. Based on the results obtained, it may be concluded that dietary NT can improve liver function in iridescent catfish, but it has no obvious positive effects on other serum biochemical parameters and stress responses.
