首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   10篇
  免费   4篇
农作物   1篇
水产渔业   12篇
植物保护   1篇
  2022年   1篇
  2021年   2篇
  2020年   2篇
  2019年   1篇
  2018年   2篇
  2017年   2篇
  2016年   1篇
  2012年   1篇
  2007年   1篇
  1995年   1篇
排序方式: 共有14条查询结果,搜索用时 296 毫秒
1.
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   
2.
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   
3.
Macquarie perch (Macquaria australasica) is a freshwater percichthyid endemic to south-eastern Australia. In view of its conservation status (indeterminate), and its importance as a sport fish, natural stocks are replenished through a breeding programme using mature stock taken from the wild each year.This paper is the first of a series of investigations instigated to understand the underlying causes of the lack of response of Macquarie perch, caught from the wild and spawned and then tankreared for a year, to hypophysation techniques. In this paper, results of physical characteristics, proximate composition and ovarian histology of wild-caught and tank-reared fish (injected with salmon GnRHa and non-injected) are presented. Oocyte diameter distribution patterns indicate that Macquarie perch spawn once each year, and that in tank-reared fish oocyte maturation is incomplete with only a small proportion of oocytes reaching maturation. The mean (sd) gonadosomatic and hepatosomatic indices of wild fish were 11.25 (2.38) and 0.59 (0.10) and that of tank-reared fish were 4.84 (0.70) and 1.44 (0.09) respectively. These two parameters differed significantly (p<0.05) in the two groups of fish.Major differences also existed in the proximate composition of the liver and the way the liver components responded to GnRHa injection. The percent (sd) protein, lipid and ash by dry weight in the liver of wild injected fish were 57.02 (0.66), 30.63 (1.22) and 8.24 (0.05) respectively while in the liver of tank-reared uninjected fish these values were 30.87 (1.36), 24.59 (1.18) and 6.43 (0.13) respectively. When expressed as an absolute amount or an amount kg–1 body weight, all of moisture, protein, lipid, ash and nitrogen free extract were greater in tank-reared than wild fish. No significant differences were observed between wild and tank-reared fish in the composition of the body musculature or the oocytes.  相似文献   
4.
The Persian Gulf is a unique and biologically diverse marine environment dominated by invertebrates. In continuation of our research interest in the chemistry and biological activity of marine sponges from the Persian Gulf, we selected the excavating sponge Cliona celata for detailed metabolome analyses, in vitro bioactivity screening, and chemical isolation studies. A UPLC-MS/MS (MS2) molecular-networking-based dereplication strategy allowed annotation and structural prediction of various diketopiperazines (DKPs) and etzionin-type diketopiperazine hydroxamates (DKPHs) in the crude sponge extract. The molecular-networking-guided isolation approach applied to the crude extract afforded the DKPH etzionin (1) and its two new derivatives, clioetzionin A (2) and clioetzionin B (3). Another new modified DKP (4) was identified by MS/MS analyses but could not be isolated in sufficient quantities to confirm its structure. The chemical characterization of the purified DKPHs 1–3 was performed by a combination of 1D and 2D NMR spectroscopy, HRMS, HRMS/MS, and [α]D analyses. Compounds 1 and 2 exhibited broad antibacterial, antifungal, and anticancer activities, with IC50 values ranging from 19.6 to 159.1 µM. This is the first study investigating the chemical constituents of a C. celata specimen from the Persian Gulf. It is also the first report of full spectroscopic data of etzionin based on extensive spectroscopic analyses.  相似文献   
5.
The present study aimed at assessing the effects of addition of thymol [0 (T0), 2.5 mg/L (T2.5), 5 mg/L (T5) and 10 mg/L (T10)] to water on biochemical and antioxidant responses of common carp, Cyprinus carpio, during 3-h transportation. The lowest dissolved oxygen and ammonia levels after transportation were related to T2.5 and T5 treatments respectively. T5 treatment exhibited lower cortisol/glucose responses after transportation and 24 h after that, whereas T2.5 and T10 exhibited elevations in these parameters at the same times. Hyperammonaemia and hyperchloraemia were observed in T2.5 treatment immediately after transportation, but such changes were observed in all treatments, 24 h after transportation. Addition of 10 mg/L thymol to water prevented uraemia after transportation, but all thymol-treated fish exhibited uraemia, 24 h after transportation. Thymol treatment failed to mitigate lactate elevation immediately after transportation; nevertheless, T2.5 and T10 had, respectively, the lowest and highest lactate levels, 24 h after transportation. T5 treatment inhibited alteration in superoxide dismutase activity, immediately after transportation, and T10 exhibited a similar effect, 24 h after transportation. Addition of 2.5 mg/L thymol to water significantly increased catalase activity immediately after transportation, but such a response was observed in all treatments, 24 h after transportation. T2.5 and T10 exhibited higher malondialdehyde levels than T0 immediately after transportation, but such a response was observed in all thymol-treated fish, 24 h after transportation. In conclusion, addition of 5 mg/L thymol is beneficial in reducing water ammonia concentration and stress in carp during transportation.  相似文献   
6.
The aim of this study was to determine the gill histopathological characteristics of Caspian roach (Rutilus rutilus caspicus) fingerlings exposed to different concentrations of potassium permanganate (PM) and formalin (FO). The fish were exposed to different PM and FO concentrations over different periods: 1 ppm PM for 24 h (1‐P24), 2 ppm PM for 24 h (2‐P24), 5 ppm PM for 0.5 h (5‐P0.5), 10 ppm PM for 0.5 h (10‐P0.5), 10 ppm FO for 24 h (10‐F24), 20 ppm FO for 24 h (20‐F24), 40 ppm FO for 0.5 h (40‐F0.5) and 80 ppm FO for 0.5 h (80‐F0.5). After exposure, gill samples were collected for histological examination. The most frequent gill histopathological symptoms were hyperplasia and epithelial lifting. The order of the gill injury index (Ig.i) among the treatments was as follow: 1‐P24, 2‐P24 < 5‐P0.5, 40‐F0.5 < 10‐F24 < 10‐P0.5, 20‐F24, 80‐F0.5. Comparing the two agents, it is concluded that there is no significant difference in the gill damages between the agents during the short‐bath treatments. However, PM causes less pathological symptoms than FO during the long‐bath treatments. Comparing the bath durations, the agents showed different behaviours. PM‐treated fish showed significantly lower gill damage during the long‐bath compared to the short‐bath treatment; whereas, pathological symptoms of FO‐treated fish was dose‐dependent for each exposure period, separately. Overall, exposure of Caspian roach to PM, at the concentrations recommended for long bath, resulted in milder gill damages compared to FO.  相似文献   
7.
The present study aimed to determine hemolysis interference in measurement of plasma biochemical parameters in fish specimens. For this purpose, blood samples were harvested from 24 Huso huso juveniles. After centrifugation, each plasma sample was divided into seven portions to make seven levels of hemolysis. Hemolysis was induced by addition of different percentages of the corresponding whole blood [0 (non-hemolyzed control group), 1, 3, 5, 10, 15, and 20% of whole blood]. Albumin, total protein, calcium, phosphorus, glucose, sodium, potassium, chloride, alkaline phosphatase (ALP), aspartate transaminase (AST), and alanine transaminase (ALT) were measured in different samples. Results showed that plasma albumin, ALP, potassium, and AST significantly increased (more than 200% at the highest hemolysis level) in the hemolyzed samples. Also, plasma total protein and phosphorus showed significant elevation in the hemolyzed samples (more than 70% at the highest hemolysis level). Plasma glucose, calcium, chloride, and ALT showed narrow but significant increase in hemolyzed samples (11.8–35.2% at the highest hemolysis level). Plasma sodium showed no significant changes in the hemolyzed samples. In conclusion, the present results show that hemolysis markedly affects plasma parameters levels, which interferes with plasma results interpretation. Therefore, analysis of hemolyzed samples should be avoided or the results should be interpreted with caution. This study encourages further investigations to develop methods for omitting the effects of hemolysis by sample blanking and/or presenting correction coefficients for measurement of plasma parameters in samples with different levels of hemolysis.  相似文献   
8.
Aquaculture International - In this study, Caspian trout, Salmo caspius (232 ± 26.9 g) were exposed to 25, 50, 100, 200, 300, 400, 600, 800, and 1000 µL/L of 1,8-cineole (cineole) to...  相似文献   
9.
Indoxacarb is a relatively new pesticide from oxadiazin class, which is used near carp ponds for agricultural purposes. Thus, the aim of this study was to determine indoxacarb effects on common carp (Cyprinus carpio). The fish were exposed to 0 (control), 0.75, 1.5 and 3 ppm of indoxacarb over 21 days and plasma biochemical characteristics and liver histopathology were examined. Exposure to indoxacarb induced fall in total protein after 21 days. Globulin increased after 7 days and then decreased after 14‐ and 21‐day exposure. Plasma alanine transaminase and aspartate transaminase activities increased in 1.5 and 3 ppm treatments after 7‐day exposure. Indoxacarb exposure significantly decreased plasma alkaline phosphatase after 7 days with no change at the second and third samplings. After 7 days, plasma T3 levels had no significant change; however, it decreased after 14 days in the 1.5 and 3 ppm treatments and also reduced after 21‐day exposure to the 3 ppm treatment compared to the control group. Plasma T4 level only decreased significantly in the 3 ppm treatment compared to the control group after 21 days. Different histopathological symptoms such as necrosis, hyperaemia, sinusoidal space extension, pyknotic nuclei, leucocyte infiltration and melanomacrophage aggregates were observed after 21‐day exposure to indoxacarb. The symptoms intensity was dependent on indoxacarb concentration. In conclusion, the present results show that indoxacarb exposure adversely affects common carp health and welfare, which consequently may induce serious problems in this species aquaculture.  相似文献   
10.
The present study aimed to investigate the effects of anaesthesia with citronellal and linalool on stress, antioxidant and hydromineral responses of common carp. Eugenol was used as control anaesthetic, as it is a common anaesthetic in aquaculture. The fish (110 ± 5.65 g) were exposed to 406 mg/L citronellal, 982 mg/L linalool or 43 mg/L eugenol within 5 min (short‐term anaesthesia) or 10 and 20 mg/L of each anaesthetic for 3 hr (long‐term exposure), before blood sampling. The results showed that the short‐term anaesthesia had no significant effects on plasma lactate, sodium, chloride and phosphorus levels and blood catalase (CAT) and superoxide dismutase activities. The short‐term anaesthesia with linalool led to higher stress responses (increased cortisol and glucose levels) and oxidative stress (increased malondialdehyde [MDA] level and decreased total antioxidant capacity [TAC] and glutathione peroxidase [GPx] activity) compared to the eugenol and citronellal. Citronellal group had significantly higher cortisol and lower TAC level and GPx activity compared to eugenol group. Under the long‐term exposure, increase in anaesthetic concentration led to significant increase in plasma cortisol, glucose and phosphorus levels. The linalool‐treated fish had significantly higher cortisol and MDA levels compared to the other groups. The eugenol group had significantly higher lactate and phosphorus and lower TAC levels compared to the other groups. Although citronellal causes slight increase in plasma cortisol level, it induces lower tissue damages compared to eugenol. Thus, citronellal might be an alternative anaesthetic for carp anaesthesia based on the present tested parameters.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号