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1.
在矿物元素的营养功能日益被揭示的同时,随着免疫营养学的发展,其对水产动物免疫机能的影响研究也逐渐深入。矿物元素作为五大营养素之一对机体免疫机能具有十分重要的作用,本文就饲料和水体中的矿物元素对水产动物免疫机能的影响做一综述。  相似文献   

2.
锌铜铁对水产动物免疫机能的影响   总被引:5,自引:0,他引:5  
矿物元素作为五大营养素之一不仅可满足水产动物的营养需求,还可加强其特异性和非特异性免疫反应。本文综述了水产动物的免疫系统及免疫相关的酶等因子,以及饲料和水体中的矿物元素锌、铜和铁对水产动物免疫机能的影响。  相似文献   

3.
维生素E(VE)是水产动物营养和饲料中最重要的维生素之一。它与水产动物机体的代谢、抗氧化能力、免疫功能、抗病力、繁殖功能等密切相关。综述了维生素E在水产动物中的生理功能和缺乏症。  相似文献   

4.
水产动物的维生素E营养研究进展   总被引:3,自引:0,他引:3  
维生素E(VE)是水产动物营养和饲料中最重要的维生素之一。它与水产动物机体的代谢、抗氧化功能、免疫功能、抗病力、繁殖功能密切相关。综述了维生素E在水产动物中的生理功能、缺乏症、需要量及存在问题。  相似文献   

5.
团头鲂营养需求与健康研究进展   总被引:1,自引:0,他引:1  
团头鲂是我国主要的大宗淡水养殖品种之一,其养殖规模在近10年不断扩大。团头鲂的营养物质需求主要以生长和营养缺乏症为评价指标。而营养物质对鱼类健康,如免疫反应和抗病力等影响的研究尚不充分。一般认为,饲料中营养物质搭配合理、品质优良有利于维持鱼类生理健康,并能保护养殖水环境。此外,一些营养物质如维生素,在鱼类的免疫机制中发挥重要作用。未来水产饲料应具有促进水产动物生长和维持健康的双重作用,通过营养调控预防鱼类疾病是保证水产养殖可持续发展的重要策略之一。本研究综述了团头鲂对蛋白质、脂肪、碳水化合物、维生素和矿物质营养需求的研究进展,以及饲料营养元素对团头鲂免疫力及抗病力影响的最新报道,以期为团头鲂高效配合饲料的开发提供科学参考。  相似文献   

6.
随着水产养殖集约化与规模化的发展,水产品为人类提供了大量优质食物蛋白质,为国家粮食安全、解决我国“三农”问题做出了重要贡献。长期研究实践证明,营养与饲料科技贡献在水产养殖中占有更加重要的地位。饲料组成不仅影响水产动物的营养,而且会影响水产动物的免疫与抗病能力,营养状况是决定水产养殖动物抵抗疾病的能力的重要因素之一。特别是在水产集约化、规模化养殖中,水产养殖动物面临着大量的应激,如:营养、环境因子等激烈变化,易诱发疾病,甚至死亡。反之,水产养殖动物的生理与健康状况也影响饲料的利用与代谢。营养和免疫的关系显著地影响着水产养殖生产,一直是大家关注的热点。在过去的5年中,水产动物营养与免疫方面的研究取得了重大进展,对蛋白质(氨基酸)、脂肪、碳水化合、维生素、矿物元素等多种必需营养素及其免疫、抗病能力等方面做了大量的研究。本文就营养与免疫相关的研究进展做一综述,以供参考。  相似文献   

7.
免疫刺激剂(immunologic stimulant)是指能够调节动物免疫系统并激活免疫机能,增强机体对细菌和病毒等传染性病原体抵抗力的一类物质.近年来,国内、外均开展了将免疫刺激剂用于水产养殖动物传染性疾病预防的研究,其主要目的是为了将免疫刺激剂用于预防使用化学药物难于奏效的水产养殖动物的病毒和细菌性疾病.本文在简要叙述水产动物的免疫防御机制的基础上,比较详细地介绍了国内、外用于水产养殖动物疾病预防的免疫刺激剂种类、特性和水产用免疫刺激剂的使用方法.  相似文献   

8.
本刊讯:水产养殖过程中发生疾病,使用抗生素进行防治,会产生抗药性细菌,并对环境造成污染,给人类食品的安全造成隐患。最近研究动向,人们已开始把注意力转移到调动或激活水产动物自身的免疫系统,提高其非特异性免疫功能和抗病力,以达到预防和抵抗养殖动物疾病的目的。目前通过提高水产动物自身免疫力来抵抗疾病的发生,已成为研究的热点。目前研究免疫增强剂按其功能而言,可以分为两大类:一类是增强水产动物的非特异性免疫功能;另一类是增强由疫苗诱导的特异性免疫功能。利用免疫增强剂预防、控制疾病,当前在水产养殖上有较好的效果。  相似文献   

9.
渔用中草药制剂是利用中草药加工而成的渔药。在我国现有渔药中,渔用中草药制剂占有比较大的比重,也能称为我国水产养殖用药物的特色之一。由于中草药中含有各种多糖类物质,对水产养殖动物使用这些药物后,可以达到增强机体的免疫机能,最终达到增强水产动物抗病能力的目的。正是因为具有这种特性,所以,将中草药渔药作为水产养殖动物疾病的预防药物是非常适宜的。此外,有一部分中草药中还  相似文献   

10.
我国水产养殖业随着集约化的发展,水产动物免疫力下降,疾病日益突出;同时药物的泛滥使用,也使整个水体的生态平衡得以破坏。中草药系纯天然、无污染且具有增强免疫力的功效,将其应用在水产养殖上具有很好的前景。本文对中草药在鱼类非特异性免疫机能方面的研究概况进行综述。中草药(Chinese herbal)用于强健机体、增强免疫功能在我国有着古老的历史和悠久的发展历程。  相似文献   

11.
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   

12.
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   

13.
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   

14.
15.
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   

16.
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   

17.
Tetrahymena is a protozoan parasite, which infects guppy, Poecilia reticulata Peters, and causes substantial economical losses in commercial farms worldwide. Studies of guppy infected by Tetrahymena require standardized infection protocols. The LD50 for Tetrahymena infection of guppies by intraperitoneal (IP) injection was calibrated, and the level obtained was 946 parasites per fish. Guppy infection with Tetrahymena by immersion, imitating the natural route of infection via the integument, was studied under normal or stress conditions. Exposure to cold and netting (CNI) and to cold only (CI) followed by immersion exposure to 10 000 Tetrahymena per mL resulted in 22.5% and 19.2% mortality, respectively, as compared to 14.2% and 10% in groups that were netted only (NI) or non‐stressed (I). Histopathology revealed that immersion infection resulted in a systemic infection. Lysozyme levels, measured 3 weeks after infection, were significantly higher in the CNI group (288 μg per mg protein) compared with CI‐, NI‐ and I‐treated groups (94.5, 64 and 62.3 μg mg?1, respectively). There was no evident parasite immobilization activity in body homogenates, suggesting no development of acquired immunity. Re‐infection by IP injection revealed no increase in protection in any of the treatment groups, mortality range of 56.3–75%, higher than in the non‐exposed control (40.6% mortality).  相似文献   

18.
Plasma estradiol-17 (E2), testosterone (T), 17,20-dihydroxy-4-pregnen-3-one (DHP) and 17,20,21-tri-hydroxy-4-pregnen-3-one (20-S) levels were measured by radioimmunoassay (RIA) in white perch (Morone americana) and white bass (M. chrysops) that were induced to undergo final oocyte maturation (FOM) with human chorionic gonadotropin (hCG). Plasma DHP levels increased in females of both species in association with oocyte germinal vesicle migration (GVM) and germinal vesicle breakdown (GVBD) and decreased thereafter. Plasma 20-S levels also increased with oocyte GVM in white bass, but were several-fold lower than DHP levels. Circulating E2 and T levels were greatest during GVM and GVBD in both species and decreased to low levels during oocyte hydration and ovulation. Follicles from white perch and white bass which received a priming injection of hCG in vivo, produced both DHP and 20-S in vitro after exposure to hCG and their oocytes underwent GVBD. Ovarian incubates from unprimed fish of either species produced only E2 and T and their oocytes did not complete GVBD. Oocytes from unprimed bass, but not perch, matured when follicles were exposed to hCG in vitro. Both trilostane and cycloheximide blocked in vitro production of DHP and 20-S and oocyte GVBD by white perch follices. DHP and 20-S were equipotent inducers of FOM in the GVBD bioassay. None of several other structurally-related steroids tested were effective within a physiological range of concentrations. These results indicate a role for DHP and 20-S in the control of FOM in white perch and white bass.  相似文献   

19.
Changes in heart rate, ventilatory activity and oxygen consumption were determined in trout (Salmo gairdneri) and brown bullhead catfish (Ictalurus nebulosus) during exposure to a steadily increasing concentration of waterborne cyanide selected to produce death in 8–9 hours for each species. The lethal cyanide concentration for the bullheads was an order of magnitude higher than for trout. Trout developed an immediate and gradually increasing bradycardia throughout the exposure period. Cyanide produced tachycardia in the bullhead followed by a gradual onset of bradycardia as the concentration of cyanide was raised. Pericardial injection of atropine (a muscarinic cholinergic antagonist) indicated that bradycardia in the trout was due initially to increased vagal tone but later due to the direct effect of cyanide on the heart. Hyperventilation in the trout persisted throughout the exposure period, although the rate and amplitude fluctuated and was variable between individual fish. During the last hour of exposure (highest cyanide concentration), ventilation was characterized by rapid, shallow breaths followed by a sudden respiratory arrest. The bullheads exhibited hyperventilation during the first 3 hours of exposure followed by a gradual, linear drop in ventilation rate and amplitude until death occurred. Cardiac and ventilatory responses in both species were attributed to stimulation of central and peripheral chemoreceptors by cyanide. Evidence is presented which suggests the initial response in the bullheads was due, at least in part, to gustatory stimulation by the cyanide. Oxygen consumption of the trout remained above pre-exposure levels for the majority of the test period. Oxygen consumption in the bullhead paralleled the changes in heart and ventilatory rates. Whole-body lactate levels of fingerlings of both species during cyanide exposure were measured to estimate the extent of anaerobiosis. Whole-body lactate levels were much greater in the bullheads than the trout, indicating a higher capacity for anaerobiosis, possibly due to a greater fuel supply. Overall, the trout responded to cyanide in a manner similar to that produced by environmental hypoxia whereas the bullheads experienced a gustatory stimulus which masked the hypoxia-like response.  相似文献   

20.
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   

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