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1.
水产动物本身不能合成类胡萝卜素,必须从食物中摄取。据专家研究结果表明,水产动物类胡萝卜素的生理功能主要表现在以下几个方面:  相似文献   

2.
虾青素是一种具有多种生理功能的类胡萝卜素,在水产动物养殖中具有重要作用。本文就虾青素的理化性质和来源,对虾青素在水产动物养殖中的着色作用、抗氧化、抗应激和提高水产动物生长、繁殖和发育性能等方面进行了综述。  相似文献   

3.
改善水产品体色的类胡萝卜素   总被引:5,自引:0,他引:5  
随着饲料工业、养殖业及动物营养研究的发展,饲料中非常规成分的作用愈来愈受到人们的重视。在水产养殖产量显著上升的同时,消费者对动物的体色也开始讲究起来。所以改善养殖水产动物体色的问题已成为目前世界各国水产动物营养学家的一个重要研究课题。近年来的研究表明:影响水产品体色的因素有水温、饲料、饲养密度、鱼体种类和大小等。而饲料中以脂肪、脂溶性维生素和色素等研究较多,色素又以类胡萝卜素方面的研究最多。  一、类胡萝卜素的性质  类胡萝卜素是一类广泛存在于动物体内的色素,主要存在于甲壳动物和昆虫的外骨骼、禽…  相似文献   

4.
虾青素在鱼类饵料中的应用研究进展   总被引:1,自引:0,他引:1  
虾青素是一种具有多种生理功能的类胡萝卜素,在水产动物养殖中具有重要作用。本文就虾青素的理化性质和来源,对虾青素在水产动物养殖中的着色作用、抗氧化、抗应激和提高水产动物生长、繁殖和发育性能等方面进行了综述。  相似文献   

5.
着色剂也称调色剂、增色剂,是改善养殖动物体色、肉质和饲料色泽的一类添加剂。近年来随着水产动物的集约化养殖和人工配合饲料的使用,导致水产动物的色泽变淡,肉质下降,严重影响了水产品的质量和商品价值,于是人们开始有意识地在饲料中添加着色剂希望改变这种情况。  相似文献   

6.
养殖鱼虾用着色剂   总被引:2,自引:1,他引:1  
除观赏性鱼类,人们喜欢鲜艳光亮的体色外,随着生活品味水平的提高,消费者对鲑鱼、鳟鱼、真鲷、红尼罗鱼、鲈鱼、对虾等体表或肉、卵的色泽也日益重视,大都喜爱深而鲜艳的色泽,所以养殖鱼虾色泽好的价格也高。因此,对鱼虾用着色剂的研究、开发与利用也就显得非常重要和迫切,本文就此方面介绍如下。 一、色素沉着的生理基础 在正常情况下,鱼虾皮肤(或肉、卵)的色泽大都来自饲料中的类胡萝卜素,这是一种黄、红色的脂溶性色素,包括胡萝卜素、隐黄素、番茄红素和叶黄素等,胡萝卜素又分α、β、γ三种。胡萝卜素和隐黄素在消化道被吸收后,在动物体内(特别是家禽效率最高)可转变为维  相似文献   

7.
水环境及饲料对水产养殖动物疾病的影响   总被引:1,自引:0,他引:1  
张庆河  曹振杰 《齐鲁渔业》2004,21(11):30-32
近年来水产养殖病害日益严重,阻碍了水产业的健康发展。病原体、环境和易感机体是疾病发生的三要素,特别是鱼类终生赖以生存的水环境,是诱发病害的主要因素。随着高密度集约化养殖的发展,人工饲料作为鱼虾最重要的物质基础,在疾病防治中起着越来越重要的作用,在已发现的鱼虾疾病中,有相当一部分为营养性疾病。本文浅要论述了水环境及饲料对水产动物疾病的影响。  相似文献   

8.
随着水产养殖业的发展,水产动物的养殖密度大幅度增加,大量投喂配合饵料在一定程度上改变了这些水产动物的生活习性。为了维持鱼虾的正常生理功能,提高生长速度,投喂优质高效的配合饲料非常重要。在饲料的基本营养指标如蛋白质、能量等满足需要的前提下,添加剂对配合饵料的质量起着关键作用。鱼虾配合饲料添加剂的种类很多,本文旨在对营养性添加剂作一介绍。一、维生素现已查明,11种水溶性维生素与4种脂溶性维生素都是水产养殖动物的必需维生素。原认为对氨基苯甲酸是必不可少的,新近研究结果表明,对氨基苯甲酸是泛酸的组成要素…  相似文献   

9.
工程鲫     
牛蛙、甲鱼配合饲料及使用技术曾训江(湖南省水产研究所413100)目前,我省的牛蛙、甲鱼养殖发展很快,使用的饵料种类繁多,配合饲料所占的比例还不大。例如甲鱼养殖多以螺蚌、鱼虾、动物内脏等为饵,牛蛙养殖以蚯蚓、鱼虾、蝇蛆等为饵,这类饵料养殖牛蛙、甲鱼有...  相似文献   

10.
我国是水产养殖大国,但是水产病害一直是制约水产养殖发展的主要因素。为治疗和预防鱼虾贝类的疾病,广泛使用各种化学药物和抗生素。长期用药,不仅使病原菌的抗药性越来越明显,而且药物残留和环境污染日趋严重,生态养殖和科学防治成为水产养殖面临的迫切问题。在长期的养殖活动中,发现采用中药如黄连、大黄、板蓝根等对水产病害有一定的防治功能。  相似文献   

11.
12.
The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna.  相似文献   

13.
Growth hormone (GH) and reproduction: a review   总被引:5,自引:0,他引:5  
Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations.  相似文献   

14.
Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China.  相似文献   

15.
16.
In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg.  相似文献   

17.
Protein and amino acid composition of the mantle of juvenile O ctopus vulgaris (Cuvier, 1797) during fasting for 27 days were determined. Average protein content of octopus mantle was of 711.19 ± 46.80 g kg?1 DW, and it decreased with increasing fasting days. The non‐essential amino acids content was higher (486.18 ± 11.08 g kg?1 protein) than essential amino acids (425.82 ± 9.15 g kg?1 protein) at the start of the experiment (unstarved animals). The results suggest that the amino acid profile of the mantle where the most abundant amino acids are Arg, His, Lys, Gly, Leu and Pro could indicate a prolonged fasting condition (>20 days) or poor nutrition of O . vulgaris. This study supports the idea of using mantle for metabolic needs of starved O . vulgaris suggesting that the degradation pathway of amino acids to pyruvate and tricarboxylic acid cycle intermediates was favoured contrary to the degradation pathway of ketogenic amino acids. Special considerations should be taken concerning Thr, Ile, Ser, Ala, Asx (Asp, Asn), Glx (Glu, Gln) (because of their fast intake) and Lys and His (due to their stable contents) during a prolonged period of fasting.  相似文献   

18.
The endemic, anadromous cyprinidChalcalburnus tarichi is the only fish species known to occur in alkaline Lake Van (Eastern Anatolia, Turkey). EightC. tarichi were maintained individually in Lake Van water (17 – 19°C; pH 9.8; 153 mEq·I–1 total alkalinity; 22 total salinity) and tank water samples analyzed for 24 h in 2 to 4 h intervals. At zero time, < 1µM ammonia was present and urea was undetectable in the tank water; at 24 h, total ammonia and urea made up 114±32 and 35±25µM, respectively. Over the experimental period, ammonia-N and urea-N excretion averaged 1041±494 and 607±169moles·kg–1 fish·h–1, respectively. The extent of urea excretion was highly variable between specimens. Uric acid excretion was not detectable.Urea was present at high concentrations in all tissues and plasma (25 – 35moles·g–1·ml–1) of freshly caughtC. tarichi; total ammonia content of the tissues was by a factor of 1.9 (liver) to 3.0 (brain) lower. High arginase activity (2.4±0.2 U·min–1·g–1) was detected in the liver ofC. tarichi but ornithine carbamoylphosphate transferase, a key enzyme of the ornithine-urea-cycle, was absent. Ureagenesis is likely through degradation of arginine and/or uricolysis. High glutamine synthetase activity (11±0.6 U·min–1·g–1) and low ammonia content in brain suggest that, like other teleosts,C. tarichi has an efficient ammonia detoxification in the brain, but in no other tissue.Nitrogenous waste excretion at alkaline pH is discussed. The ability ofC. tarichi to excrete high levels of ammonia at extremely alkaline pH is unique among teleosts studied so far. The mechanism of ammonia excretion under Lake Van conditions remains to be elucidated.  相似文献   

19.
Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL?1 (1.25 ng well?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation.  相似文献   

20.
  1. Humanity is facing a biodiversity crisis, with freshwater-associated biodiversity in a particularly dire state. Novel ecosystems created through human use of mineral resources, such as gravel pit lakes, can provide substitute habitats for the conservation of freshwater and riparian biodiversity. Many of these artificial ecosystems are subject to a high intensity of recreational use, however, which may limit their biodiversity potential.
  2. The species richness of several taxa (plants, amphibians, dragonflies, damselflies, waterfowl, and songbirds) was assessed and a range of taxonomic biodiversity metrics were compared between gravel pit lakes managed for recreational fisheries (n = 16) and unmanaged reference lakes (n = 10), controlling for non-fishing-related environmental variation.
  3. The average species richness of all the taxa examined was similar among lakes in both lake types and no substantial differences in species composition were found when examining the pooled species inventory. Similarly, there were no differences between lake types in the presence of rare species and in the Simpson diversity index across all of the taxa assessed.
  4. Variation in species richness among lakes was correlated with woody habitat, lake morphology (surface area and steepness), and land use, but was not correlated with the presence of recreational fisheries. Thus, non-fishing-related environmental variables had stronger effects on local species presence than recreational fisheries management or the presence of recreational anglers.
  5. Collectively, no evidence was found that anglers and recreational fisheries management constrain the development of aquatic and riparian biodiversity in gravel pit lakes in the study region; however, the conservation of species diversity in gravel pit lakes could benefit from an increasing reliance on habitat enhancement activities.
  相似文献   

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