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The effect of a synthetic curcumin analogue (salicylcurcumin) on fish lipid peroxidation was investigated in both in vitro
and in vivo conditions using a teleost model Anabas testudineus (Bloch). Curcumin analogue inhibited the formation of lipid peroxidation products and thiobarbituric acid reactive substances
(TBARS) content at the three concentrations (10−2 M, 10−3 M and 10−4 M) in vitro. TBARS content was reduced by 80% in the liver and 68% in brain by the higher concentration of salicylcurcumin.
For in vivo study, salicylcurcumin (0.5%) was supplemented along with the basal feed for a period of 60 days. It produced
a 60% reduction in liver TBARS content. The antioxidant enzyme superoxide dismutase (SOD) was stimulated, whereas catalase
(CAT) and glutathione peroxidase (GPx) were inhibited. Glutathione (GSH) was reduced and glutathione reductase (GR) unchanged.
Even though there was an increase in SOD activity, the CAT and GPx did not increase accordingly, maybe due to the direct scavenging
of H2O2 by salicylcurcumin. The protein content also increased in the curcumin-fed animals, indicating a positive growth-promoting
effect. Therefore, it would be beneficial to supplement salicylcurcumin along with the aquaculture feed in order to help the
fish to cope with adverse conditions in the environment. This would increase the survival rate, disease resistance and ultimately
the growth rate. 相似文献
3.
‘Gher’ farming is a unique system that incorporates the joint operation of three enterprises: freshwater prawn, fish and HYV
rice and is expanding rapidly in the coastal regions of Bangladesh. In this paper we evaluate the performance of this unique
system in terms of the existence of diversification economies (amongst the three integrated enterprises), scale economies
and technical efficiency using a stochastic input distance function approach on a sample of gher farmers. The results reveal
evidence of a diversification economy in the rice–carp combination. Economies of scale exist in the ‘gher’ farming system.
The level of technical efficiency is estimated at 68% implying that a substantial 47% [(100−68)/68] of potential output can
be recovered by removing inefficiency. Significant efficiency gains are made from diversification amongst these enterprises.
Also, the education of farmers and the female labour input significantly improve efficiency whilst larger operation size reduces
efficiency. The key policy implication is that the diversification of enterprises, particularly the rice–carp combination,
is beneficial and should be promoted. Also investment in education and creation of a hired labour market for females would
improve technical efficiency. 相似文献
4.
There has been much recent discussion about the idea that large whales are potential competitors with fisheries for available marine resources. Based on this idea, often referred to as the ‘whales eat fish’ conflict, culling whales has been proposed as a way to increase resources available for human consumption and thereby ensuring global food security. However, the scientific basis for such arguments remains unclear, especially in the Caribbean waters where baleen whales generally do not feed. In this article, we (i) develop an ecosystem model describing the trophic interactions between whales, fish and fisheries in the Caribbean waters, (ii) calculate the level of overlap between cetaceans and fisheries for food resources, and (iii) simulate the removal of cetaceans from the Caribbean waters in order to quantify the potential increase in available biomass of commercially important fish. Ten groups of cetaceans are considered in the model, including baleen whales, toothed whales and small cetaceans. Our results suggest that baleen whales are not a threat to fisheries in Caribbean waters, while toothed cetaceans seem to be more impacted by fisheries than they actually impacting them. Whales target different types of food resources and consume significantly less than what is taken by fisheries. Moreover, simulated reductions in large whale abundance do not produce any appreciable increase in biomass of the commercially important fish species. In some cases, the presence of some whales actually improves fishery yield as a result of indirect predation effects. 相似文献
5.
Natascha Wosnick Hugo Bornatowski Carolina Ferraz André Afonso Bianca Sousa Rangel Fábio Hissa Vieira Hazin Carolina Arruda Freire 《Fish physiology and biochemistry》2017,43(1):165-178
Sharks are very sensitive to stress and prone to a high mortality rate after capture. Since approximately 50 million of sharks are caught as bycatch every year, and current recommendations to reduce the impact of commercial fishing strongly support immediate release, it is imperative to better understand post-release mortality caused by the stress of capture and handling. Blood samples allow the assessment of stress levels which are valuable tools to reduce mortality in commercial, recreational and scientific fishing, being essential for the improvement in those conservation measures. Biochemical analyses are widely used for sharks as stress indicators, with secondary plasma parameters (lactate, glucose and ions) being the most often employed assays. However, it is virtually impossible to determine baseline plasma parameters in free-ranging sharks, since blood withdrawal involves animal capture and restrain, which are stressful procedures. This study aims at analyzing secondary parameters of five healthy tiger sharks captured with circular hooks and handlines in Fernando de Noronha (Northeastern Brazil) and comparing them with secondary parameters of three dead tiger sharks caught off Recife (also Northeastern Brazil). The results showed that the analysis of some plasma constituents in dead animals may be an efficient tool to assess stress and lethality. However, traditional parameters such as glucose and calcium, need to be used with caution. The results also demonstrated the extreme importance of urea and phosphorus for assessing stress response and mortality in tiger sharks, both parameters frequently neglected and of utmost importance for shark’s homeostasis. 相似文献
6.
Due to problems with bone deformities in farmed Atlantic salmon, there is a growing interest in the possible involvement of
vitamin K in normal bone development, and sensitive biomarkers for evaluating vitamin K status are therefore needed. The vitamin
K-dependent (VKD) enzyme γ-glutamylcarboxylase (GGCX, EC 6.4.x.x) requires vitamin K as a cofactor for its post-translational
modification of glutamic acid (Glu) residues to γ-carboxyglutamic acid (Gla) residues in VKD proteins, and is required for
their function in haemostasis and bone metabolism. The present study was designed to evaluate the enzyme assay for GGCX activity
in isolated liver microsomes and its distribution in the tissues of Atlantic salmon. The effect of KH2 and menadione on the GGCX activity in salmon liver was also compared. Results from the present study show a widespread tissue
distribution and expression of GGCX in Atlantic salmon. The GGCX activity and ggcx expression in all bony tissues examined imply the presence of vitamin K, and suggest the involvement of vitamin K in bone
metabolism of Atlantic salmon. We propose the GGCX assay as a sensitive marker for vitamin K status, and confirm that menadione
does not work as a cofactor for GGCX in Atlantic salmon liver. 相似文献
7.
The full-length cDNA, encoding the orange-spotted grouper β-actin and spanning 1920 bp including a poly (A) tail, was cloned
from its brain cDNA library. The open reading frame encodes a protein of 375 amino acids. Sequence analysis indicated that
it contained the typical structural features of cytoplasmic actins, and showed higher homology with other vertebrate β-actin
than any other members of the actin family. The partial genomic sequence indicated that the organization of the β-actin gene
in the orange-spotted grouper might also be conserved. Northern blot analysis indicated that it was expressed at high levels
in the brain, spleen, adipose tissue, ovary, and liver, but at low levels in the gill filament and heart, and at a very low
level in the kidney. The expression of β-actin gene in the skeletal muscle was barely detectable. These results indicated
that the expression of the orange-spotted grouper β-actin gene showed significant variation in different tissues. Therefore,
caution should be taken when using β-actin gene as an internal control in the normalization of gene expression among tissues.
Whereas, semi-quantitative RT-PCR analysis indicated that treatment with 17α–methyltestosterone (MT) had little effect on
the mRNA expression of β-actin gene in the in vitro incubated hypothalamus, pituitary, and ovary fragments of the orange-spotted grouper, suggesting β-actin can be used as an
internal control for RT-PCR analysis of MT effects on gene expression in these tissues. 相似文献
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D. V. Garina V. A. Nepomnyashchikh A. A. Mekhtiev 《Fish physiology and biochemistry》2016,42(4):1137-1141
Serotonin-modulating anticonsolidation protein (SMAP) can impair the formation of memory traces in mammals and fish. We have studied the influence of SMAP on behavioral lateralization of juvenile carps Cyprinus carpio in a T-maze without food reinforcement in three experimental groups (n = 8 each): (1) negative control (intact animals); (2) experimental group (fish injected ICV with SMAP; 2 μl, 1.2 mg ml?1) and (3) active control group (fish injected ICV with inactivated SMAP). The behavioral lateralization of carps was observed on the 1st, 2nd, 3rd and 6th days after the injections. In each observation session, a fish was placed five times in a start chamber of the T-maze. The direction of the turn upon leaving the start chamber, as well as the latency from the opening of start chamber flap to the fish’s turn was registered. The number of right turns (of all five turns observed during the session) was a criterion of lateralization. It was found that carps have no inherent preference for turning left or right. The SMAP injection did not influence the choice of turning direction, but increases latency values insignificantly. The results are important for the correct interpretation and clarification of data reporting the role of SMAP in training and formation of spatial memory of fish in a maze. 相似文献
11.
Hallgren S Volkova K Reyhanian N Olsén KH Hällström IP 《Fish physiology and biochemistry》2011,37(4):911-918
Behaviour studies are used in toxicology research as they are excellent tools to measure physiological end-points caused by
exogenous chemicals. In mammals both reproductive and non-reproductive behaviours have been used for a long period of time,
whereas in teleost fishes non-reproductive behaviours have received little attention compared to reproductive behaviours.
Recent advances in measuring stress related behaviours in zebrafish have provided additional tools to understand behaviour
toxicology in fish. One species with well documented reproductive behaviour disturbed by different toxicants is the guppy,
which is better suited than zebrafish for reproductive behaviour studies and therefore might be a better model organism for
comparative behaviour studies in fish toxicology. Here we report new applications for non-reproductive behaviours in guppy
and test these behaviours on males treated with the endocrine disruptor 17α-ethynylestradiol at environmentally relevant concentrations.
17α-ethynylestradiol increased freezing and bottom-dwelling when fish were placed in a non-familiar aquarium, but did not
significantly affect shoaling behaviour. These results are similar to the anxiogenic behaviours seen in rats treated perinatally
with 17α-ethynylestradiol and add more concern to the impacts of endocrine disruptors on aquatic wildlife. 相似文献
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Xiao Hui Li Jun Jie Bai Xing Ye Yin Chang Hu Sheng Jie Li Ling Yun Yu 《Fisheries Science》2009,75(2):351-358
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Carla Patricia Bejo Wolkers Mônica Serra Augusto Barbosa Júnior Elisabeth Criscuolo Urbinati 《Fish physiology and biochemistry》2017,43(3):755-759
Fluoxetine (FLX) is a selective serotonin (5-HT) reuptake inhibitor known for its effects modifying aggressiveness, personality traits, and anxiety-like behaviors. The aim of the present study was to evaluate the influence of the acute treatment, by immersion, with FLX on aggressive behavior of resident Brycon amazonicus fish. Fish pretreated with FLX presented an increase in aggressiveness, evidenced by the increase on the number of bites and chases against the intruder and a decrease in latency for the first attack, when compared to control fish. Together with previous studies, these results show the complexity of the neural modulation of the aggressive behavior in fish by 5-HTergic system. 相似文献
15.
Misako Urabe Kentaro Nakai Daigo Nakamura Masaharu Tanaka Toshio Nakatsugawa Kazuo Ogawa 《Fisheries Science》2009,75(1):63-70
An introduced pathogenic fish trematode, Parabucephalopsis parasiluri Wang, 1985 (Digenea: Bucephalidae), was studied to determine the seasonal fluctuation in its metacercariae abundance. The
timing of the recruitment period of the metacercariae and the relationship between yearly fluctuation in metacercarial abundance
and some environmental factors were also examined to develop an effective plan for disease control. Monthly changes in metacercarial
abundance in the caudal fin of pale chub (Zacco platypus) and of the prevalence of the first intermediate host (golden mussel Limnoperna fortunei) suggest that P. parasiluri generally has an annual life cycle. The metacercarial abundance in chub increased when the water temperature fell below 7°C
in winter, but the rapidity of the increase varied between 2007 and 2008. The fluctuations in the abundance of metacercariae
in winter from 2001 to 2008 showed that mean flow rate and mean water level in January were negatively related to the infection
level each year, and positively related to the mean water temperature. Based on these results, we propose a control plan for
parabucephalopsiosis involving discharge control; that is, more than 50 m3/s (corresponding to 150 m3/s in the Yodo River) of water should be flushed from upstream dams for a period of at least one week starting on the day
when the water temperature falls below 7°C. 相似文献
16.
Arun M. Chilke 《Fish physiology and biochemistry》2010,36(4):911-915
Liver is the metabolic factory and contains several valuable enzymes that catalyze biochemical reactions. β-glucuronidase
is one of the well-known lysozymes that participates in the carbohydrate metabolism in the tissues of various vertebrates.
In the present study, an attempt was made to study the kinetic properties of hepatic β-glucuronidase of the Indian major carp
(IMC), Labeo rohita. It was observed that the enzyme activity increased largely at pH 5 (0.1 M acetate buffer) when exposed to 38°C. However,
the maximum activity was noticed at 52°C and later it started declined up to 70°C. It was also observed that with time the
enzyme activity increased until substrate was completely used up. It has been concluded that it is a heat stable enzyme and
cannot be destroyed at room temperature. Enzyme activity was observed to increase in response to increase in enzyme and substrate
concentrations. The reaction velocity maxima (Vmax) and Michaelis constant (Km) were recorded using Lineweaver–Burk plot that
was 18.182 μg/h and 2.907 mM, respectively. 相似文献
17.
为了实现由应试教育向素质教育的转变 ,适应现代社会对高素质人才的需要 ,必须加强素质教育 ,而实现素质教育的核心问题是提高课堂教学质量 ,因此 ,创设最优化课堂教学、促进学生个性健康发展和素质的全面提高是极其必要的。本文拟就这一问题 ,举《淡水生物学》教学中之例 ,谈谈粗浅的“五字法”。一、精指授课“精”和板书“精”。1、授课“精”。教师讲课时照本宣科 ,会使学生无所适从 ,觉得枯燥乏味 ,甚至于“丢了西瓜 ,拣了芝麻”。因此 ,教师应深入钻研教材 ,挖掘课程体系 ,找出每章、每节课的难点和重点 ,分清轻重、强弱 ,强化重点和… 相似文献
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Michele Pellizzato Thomas Galvan Raoul Lazzarini Pierpaolo Penzo 《Aquaculture International》2011,19(3):541-554
Currently, Tapes philippinarum, the Manila clam, is the primary fishery resource for about 1,000 fishermen and aquaculturists in the Venice Lagoon. The
recruitment of this clam is a key component supporting shellfish culture industry that is almost completely dependent on the
gathering of wild clam seed in nursery areas where the juveniles accrue at high densities as a consequence of favourable environmental
conditions. The objective of the present study was to identify the areas optimal for the recruitment of T. philippinarum, herein referred to as nursery areas, and to evaluate the recruitment success each year for the period 2002–2007. Sampling
was conducted with a hydraulic dredge at 25 stations, in at least three separate periods from April to September each year
for 2002, 2003 and 2004, and at 15 stations for 2005, 2006 and 2007. The zero-year cohorts of this species were usually first
detected in bottom samples in late spring (May and June). Some setting appears to occur throughout the summer. The peak of
seed density, expressed as number of individuals retained on a 1-mm mesh screen per square metre of sampled substrate, was recorded in September. Measurable fluctuations in annual recruitment have been observed, with peak densities of juveniles in 2002 and 2003 (about
2,000/m2) and minimum densities in 2006 (about 44/m2). In the summer 2007, densities over 30,000/m2 were found at the mouth of the River Brenta, immediately adjacent to the southern end of the Venice Lagoon. These intensive,
multiyear surveys of this species furnish critical information on seasonal reproduction patterns and recruitment success,
which is essential for the rational development of a local fishing master plan and for the formulation of a management strategy
for sustainable utilisation of this shellfish resource in the Venice Lagoon. 相似文献
19.
1. The aim of this paper is to assess the usefulness of surveying young fish assemblages in tributaries of the Sinnamary River (French Guiana, South America) as a means of assessing fish species diversity and monitoring environmental change in a neotropical river subjected to hydrodam operations. 2. This work confirms that the tributaries of the Sinnamary River are nurseries for more than half the fish species present in the river. 3. It shows that in natural conditions the young fish assemblages at the beginning of the dry season are overwhelmingly dominated by Characiformes, but that species of other orders are favoured in the impacted sections. 4. This study confirms that the evaluation of the reproductive success of the different fish species over large river stretches at the end of the rainy season appears to be an appropriate method for detecting the immediate effects of flow disturbances on fish communities. 5. The results suggest that it is more informative and less time‐consuming to consider the abundance of juveniles only, and to group them at the order level instead of calculating diversity indices. 6. The relative abundance of Characiformes juveniles at the end of the rainy season seems a cost‐efficient way of assessing the hydrological impact of the dam on the Sinnamary River, and this may be the case for other neotropical rivers where these methods may be generally applicable. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
20.
We examined spatial and temporal variations in the species composition of two seagrass species, Zostera marina and Z. caespitosa, in a lagoon facing the Sea of Okhotsk. We also considered how those variations affected habitat quality for motile epifauna, especially for a commercial shrimp. A long-interval comparison between 1996 and 2013 showed that seagrass species composition in the lagoon did not vary, while their relative abundances did. A survey in 2012 revealed that the abundance of Z. caespitosa was affected by the abundance of Z. marina, water depth, and location in the lagoon. Although these seagrass species have similar aboveground morphology, differences in their fine structures were detected. Diversities of motile animals inhabiting the seagrass species were the same. Differences in seagrass utilization were observed when we focused on a commercial shrimp, Pandalus latirostris. This shrimp always preferred higher densities of shoots irrespective of the species and seasonally changed their preference for the number of leaves per shoot. They were therefore more abundant in Z. caespitosa, which had those structural characteristics. The results suggest that the management of shrimp resources could be improved by flexibly changing protected areas in accordance with the dynamics of seagrass distribution in the lagoon. 相似文献