鱼类的摄食感觉

鱼类的摄食感觉是决定鱼类摄取食物与否的关键,也是鱼类营养学研究的基础.文章简要介绍了鱼类的摄食感觉器官--嗅觉、味觉、侧线、视觉的结构和功能,不同感觉器官在鱼类摄食过程中的作用以及不同感觉器官的反应在摄食过程中的关系.     

鱼类电感受器的种类、结构与作用模式

鱼类的电感受器,是一种特殊的侧线器官,与机械感受器官同属于侧线感觉系统。电感受器可以感受到生存环境中的弱电场,在鱼类的定位、交流、摄食等行为中发挥着重要的作用。电感受器的种类分为壶腹型电感受器和结节型电感受器,其作用模式分别为主要用于摄食和逃避敌害的"被动模式"和用于电定位与电交流的"主动模式"。研究鱼类电感受器的目的,一方面为了深入了解鱼类的进化意义和生物学特性,并在生态养殖或捕捞中有效地利用鱼类的电感受的特性,以提高增养殖或负责任捕捞技术。另一方面,有利于更好地研究和保护鲟鱼等电觉鱼类资源。     

半滑舌鳎摄食机理及营养策略

目前半滑舌鳎苗种培育技术方面已经取得重大突破，然而，由于半滑舌鳎在人工养殖条件下投喂困难，产业化养殖规模仍受到限制。为了解决半滑舌鳎的投喂摄食难题，本文对其捕食特征、摄食机理等进行了深入研究，并综合分析了半滑舌鳎摄食机理的最新研究成果。认为半滑舌鳎摄食机制具有两种模式：（1）对运动状态饵料，利用机械感觉定位（侧线），利用化学感觉识别（口咽腔味蕾）；（2）对静止状态饵料，利用化学感觉定位（嗅觉），利用机械感觉识别（无眼侧乳头状突）。基于半滑舌鳎的摄食机理，作者认为，对半滑舌鳎营养策略问题，应从在饵料中添加诱食剂增强嗅觉刺激和强化侧线刺激两方面来进行研究。     

鱼类摄食行为的化学感觉调节

<正> 摄食行为是动物赖以生存的基本行为之一,自从 Strieck(1924)第一个进行鱼类摄食行为试验之后,逐渐地证实了化学感觉对鱼类摄食行为的调节作用,60年代电生理技术的发展,对于味觉生物电反应的研究,进一步揭示了这种调节的生理机制,学者们对于鱼类化学感觉和摄食行为的基础理论研究,使我们能够掌握这些生理活动的规律性为生产实践服务,例如生产饲料添加剂,改变饵料的味道,使原来不爱吃的、但又富有营养的饵料变为适口饵料,既可以扩大饲料     

鱼类摄食行为的感觉基础

感觉器官在摄食行为上的作用,是研究鱼类行为和感觉的一个基本方向。本文的目的是对有关鱼类摄食行为的感觉基础这一问题的现状进行分析。摄食是一些单独的行为时相或动作依次交替的复杂过程。它由机体获得环境中的食物信号开始,终止于最后将其吞食或摒弃。摄食行为的特殊之处是鱼的感官无例外地全部参与其中。由于这类行为的复杂性和多感觉特征,在分析其感觉基础时,必须预先将其划分为一些阶段或时相,这样做还与鱼类生态(包括营养生态以及摄食类型和方式)的多样性有关.     

达氏鳇稚鱼感觉器官在摄食行为中的作用

通过选择性封闭达氏鳇(Huso dauricus)稚鱼不同感觉器官(包括视觉、嗅觉、触觉、侧线感觉、电感觉、嗅觉+触觉、嗅觉+触觉+电感觉),研究其在达氏鳇稚鱼摄食行为中的作用,旨在为达氏鳇的资源保护和人工培育提供科学依据。实验鱼受精卵采自黑龙江抚远江段,经过开口饲养56 d,随机选择120尾体质健壮的稚鱼用于实验。实验鱼体长为(13.98±1.27)cm,体重为(17.32±4.31)g,在实验开始前暂养适应15 d,实验设计7个实验组和1个对照组。实验持续12 d,期间水温维持在25.2~27.5℃;1 h摄食实验显示,封闭视觉、侧线感觉或触须后稚鱼的摄食量与正常稚鱼(对照组)无显著性差异(P0.05)。结果表明,封闭嗅觉、嗅觉+触须、电感觉、电感觉+嗅觉+触觉时,平均每尾达氏鳇稚鱼摄食量分别为正常水平的69.1%、63.0%、54.3%与43.9%,且差异显著(P0.05),说明电感觉和嗅觉在达氏鳇稚鱼期的摄食中起重要作用;延长摄食实验时间时,达氏鳇稚鱼可能产生了摄食定势与习惯,电感觉和嗅觉的摄食作用并不明显。     

鳜鱼摄食感觉机制及饵料投喂技术

鳜鱼 (Ｓｉｎｉｐｅｒｃａｃｈｕａｔｓｉ)又名桂鱼、桂花鱼、季花鱼、鳌花鱼等 ,是典型的淡水底栖凶猛性鱼类。由于其具有肉嫩、味美、少刺的特点 ,自古以来就是人们所喜爱的美味佳肴 ,并有“淡水石斑鱼”之美称。它是一种经济价值很高的名贵食用鱼 ,近年来受到各地养殖单位和养殖户的喜爱。由于鳜鱼特殊的食性 ,人工养殖过程中饵料及其投喂技术就成为鳜鱼养殖成功的关键技术。本文拟从鳜鱼的摄食感觉机制来分析鳜鱼的食性 ,并据此介绍鳜鱼的饵料投喂技术。1　鳜鱼摄食感觉机制1 1　视觉和侧线在鳜鱼捕食行为中视觉和侧线起主要作用。视觉…     

鱼类早期发育阶段摄食行为研究现状

对鱼类早期阶段的摄食行为研究进行了综述。重点阐述了胃含物分析法、饥饿对摄食的影响、摄食器官的形态发育特征与摄食行为的关系、食物选择及其生理生态因子对摄食的作用。初步探讨了仔稚鱼饥饿后的捕食量和捕食速度的变化,并结合食物保障,分析了食物选择性指数I在鱼类摄食行为研究中的应用。     

pH对鱼类化学感觉的影响

关于硬骨鱼类的嗅、味感觉器官在解剖学和生理学方面的研究成果，许多学者都发表过综述文章(Kleerekoper1969，Bardach和Atema1971，Bardach和Villars1974，Kapoor等1975，Brown和Hara1982，Tucker1983)，最近十几年，对于鱼类化学感觉的电生理研究，主要在于一些天然物质、氨基酸及其衍生物对于嗅、味觉系统的相对刺激效果，刺激物的分子结构与刺激效果的关系，以及刺激物与感受细胞膜上的感受点相互作用的机制，而对于人为因素如捕捞、环境因素pH、污染对鱼类嗅、味觉的影响报导甚少(Hara1976，1978，Konishi等1969，Tucker1973，Silver，1978，Cancolon1980，Hidaka1970)。鱼类的嗅、味觉在鱼类生命活动如摄食、洄游、生殖、逃避敌害、群体的控制等等行为中起重要的作用，当人们利用鱼类嗅、味觉的一些生理活动规律为生产实践服务时，pH是不可忽视的一个因素，本试验以重要的生物信息分子氨基酸为刺激物，研究pH对于鱼类嗅、味觉系统对氨基酸敏感性的影响。     

鱼类嗅觉系统功能与行为生态研究进展

嗅觉是鱼类重要的感觉之一,鱼类可通过嗅觉感知环境中的刺激物而获得环境信息,在其行为生态中有着重要作用。近年由于气候变化和水质污染,鱼类嗅觉行为生态也备受关注。对鱼类嗅觉器官结构、嗅觉差异、嗅觉定向机制等进行了综述,并探讨了鱼类种间、种内个体识别,摄食,生殖,洄游,领地防御等行为生态中嗅觉的作用和机制。总结鱼类嗅觉行为生态机制的研究,有助于了解鱼类行为与环境的适应性,同时对水产养殖业也有重要的指导意义。     

半滑舌鳎头部无眼侧皮肤表面特殊感受器的电生理反应

采用电生理学方法对半滑舌鳎头部无眼侧皮肤表面特殊感受器的感觉生理功能进行研究。结果表明,机械刺激时,无眼侧特殊感受器神经产生诱导放电信号,表明无眼侧特殊结构能对机械刺激产生反应;化学物质刺激时,随着反应浓度的增加,无眼侧特殊感受器神经的诱导信号的反应幅度和频率明显增加,表明无眼侧特殊结构对化学刺激产生反应;不同化学物质刺激强弱顺序:沙蚕提取液>L-精氨酸>L-甲硫氨酸>L-赖氨酸>L-组氨酸>二甲亚砜>L-甘氨酸>L-丙氨酸。实验表明,无眼侧特殊结构具有对机械刺激和化学刺激产生反应的双重感觉功能。据推测,这种皮肤感觉器官可能是一种与摄食有关的,在摄食中发挥积极作用的体表感觉器官。     

鳜养殖概况及摄食调控机制研究进展

鳜是我国名贵的淡水经济鱼类,2019年其养殖产量已达33万t。本文从养殖现状、养殖模式及良种选育等方面介绍鳜的养殖概况。同时,鳜摄食习性独特,终生以活鱼为食。养殖生产中,主要以活饵料鱼直接饲喂,这种以鱼养鱼的方式不仅资源利用率低,对环境和资源的破坏也极大。据此,本文从环境因素和饵料性质等方面概述了影响鳜摄食的外在因素,并从摄食感觉器官和摄食调控因子剖析鳜摄食特性的内在因素,这有助于通过人工干预的方式调整鳜的摄食习性,为其转食配合饲料提供必要的支撑。此外,需加强鳜摄食调控机制及营养生理需求特性的研究,实现鳜配合饲料的突破,促进其养殖业的绿色健康发展。     

Feeding behavior under dark conditions in larvae of sutchi catfish <Emphasis Type="Italic">Pangasianodon hypophthalmus</Emphasis>

Sutchi catfish Pangasianodon hypophthalmus hatch with morphologically immature sensory organs; however, sensory organs develop rapidly with larval growth. Two-day-old larvae commenced ingesting Artemia nauplii. The larvae displayed many taste buds on the barbels, the head surface, and in the buccal cavity. Other sense organs were also well developed at this stage. Feeding experiments revealed that 2-day-old larvae ingested Artemia under both light and dark conditions, moreover, the larvae could ingest frozen dead Artemia. The ingestion rates for 4- and 7-day-old larvae were significantly higher under dark conditions than under light conditions. The rates using frozen dead Artemia were mostly higher than the rates using live Artemia. Therefore, feeding behavior under dark conditions is most likely not mediated by visual or mechanical senses, but rather by chemosensory senses, such as taste buds. Larval fish are vulnerable to predators; thus, if they can search for and eat food at night, they can avoid diurnal predators. The behavior observed here appears to represent their survival strategy. Moreover, these results suggest a new possibility that sutchi catfish larvae can be reared under dark or dim light conditions in order to improve survival and growth rates as in the case of African catfish Clarias gariepinus.     

Effect of dietary taurine levels on growth and feeding behavior of juvenile Japanese flounder Paralichthys olivaceus

This study was conducted to investigate the effect of dietary taurine levels on growth and feeding behavior of juvenile Japanese flounder. Three different taurine level diets were prepared by supplementation of taurine (T-0%, 0.5% and 1.5%) to the basal diet. Fish meal washed with 70% ethanol to remove taurine was used as the sole protein source. Feeding experiments were carried out twice at 20 °C by using different size of fish (average body weight: 0.3 g in Experiment I and 3.7 g in Experiment II). The feeding behavior of fish was observed throughout the experimental period. At the end of experiments, fish were killed for amino acids analysis.

The final average body weight and feed efficiency of juvenile Japanese flounder fed the T-1.5% diet was significantly higher than those of fish fed the T-0% diet in Experiments I and II. Abnormal feeding behavior such as multiple feeding while swimming in the water column was observed in the T-0% group in Experiment I. These findings indicate that taurine is essential for normal growth and development of normal feeding behavior of juvenile Japanese flounder.     

Reduced stress and increased immune responses in Nile tilapia kept under self-feeding conditions

ABSTRACT: Stress and immune responses were studied in Nile tilapia Oreochromis niloticus under both conditions of self-feeding and scheduled feeding. Self-feeding fish had a significantly lower cortisol level in their blood plasma than that of scheduled feeding fish. Furthermore, skin color was found to be paler in the self-feeding fish compared with that of the scheduled feeding fish. Thus, the self-feeding fish had a less stressful physiological status than the other experimental fish. Immunological analyses revealed that the self-feeding fish significantly exceeded the scheduled feeding fish in the phagocytic activity of their macrophages, antibody production, and the number of blood-circulating lymphocytes. The higher immune responses of self-feeding fish seem to be attained through a less stressful environment. This self-feeding behavior could be exploited to create reduced stress for disease control in fish farming.     

Acoustical monitoring of fish density,behavior, and growth rate in a tank

A challenge for the aquaculture community has long been the development of harmless techniques for monitoring fish in a tank. Acoustic telemetry has been used to monitor fish swimming behavior, and passive acoustics have been used to monitor fish feeding, but new techniques are needed to monitor non-invasively their numbers and growth rates. Recently, it has been demonstrated that the acoustical total scattering cross section of fish swimming in a tank can be measured from multiple reverberation time series. These measurements have been used successfully to estimate the number of fish in a tank in laboratory conditions, and to characterize their acoustical signatures. Here, we introduce a novel method for acoustically monitoring fish numerical density and behavior, and measuring their growth rates over long periods of time. These measurements can be performed remotely, without human interaction with the fish, and are harmless. To demonstrate the efficiency of these techniques, the number of sea bass, as well as the behaviors of sardines, rockfish and sea bass, in different tanks were monitored. Also, the growth rates of a group of starved sardines and a group of fed sardines were measured acoustically, over 1 month. For comparison, their average weight was measured once per week.     

闽南-台湾浅滩渔场狗母鱼类食性的研究

本文对闽南一台湾浅滩渔场狗母鱼类(多齿蛇鲻、花斑蛇鲻和大头狗母鱼)的食料生物组成、摄食强度的季节变化以及消化器官与食性等方面进行了探讨。结果表明，这三种狗母鱼类都属于游泳动物食性的底层鱼类，而且是同种残食的中级肉食性鱼类，其食料生物组成比较简单，主要摄食鱼类和头足类，还兼食长尾类、短尾类和口足类。被捕食对象的大小，随着捕食对象(多齿蛇鲻或花斑蛇鲻)叉长的增加而增大。狗母鱼类周年均有摄食，多齿蛇鲻和花斑蛇鲻在产卵盛期(3—4月)摄食强度较高。它们的消化器官的形态结构与其肉食性相适应，多齿蛇鲻和花斑蛇鲻的消化器官和食性相近似，比大头狗母鱼的食性较凶猛。     

不同营养状况对鲫鱼偏好游泳速度的影响

为考察不同营养状况对鲤科鱼类偏好游泳速度的影响,本研究以鲫鱼(Carassius auratus)为实验对象,(25±1.0)℃条件下设置3个不同营养状况实验组:对照组(禁食48 h)、饱食组(饱食)和饥饿组(饥饿14 d),将单尾实验鱼置于梯度流速选择仪(流速范围为11.86~65.45 cm/s,等距离划分为5个流速区域,从第一到第五流速区域流速连续增加)中拍摄1 h,采用Ethovision XT9软件分析视频资料并计算实验鱼在不同流速区域平均进入频次(F,次)、单次进入停留时间(T,s/次)和平均停留时间百分比(P_t,%)等流速选择行为指标。结果显示,对照组和饱食组的F值随水流速度上升而增加,对照组的T值不同流速区域间无差异(P0.05),而饱食组第三和第四流速区域T值均显著大于其他流速区域(P0.05),因此两实验组第三和第四流速区域的P_t均显著大于其他流速区域,其偏好游泳速度为20.12~41.30 cm/s。饥饿组流速偏好行为出现表型分化,I型实验鱼在第一流速区域P_t和T值显著大于其他流速区域(P0.05),各流速区域的F值均显著小于其他实验组(P0.05),故I型实验鱼的偏好游泳速度为11.86~15.18 cm/s。而II型实验鱼则与对照组相似,在第三和第四流速区域Pt均显著大于其他流速区域(P0.05),故II型实验鱼的偏好游泳速度为20.12~41.30 cm/s。结果表明,饱食不影响鲫鱼的偏好游泳速度,可能是饱食不影响鲫鱼的游泳能力所致,但饱食组在各流速区域间的出入频次减少而停留时间有所增加。饥饿后鲫鱼偏好游泳速度出现表型分化,I型实验鱼的偏好游泳速度降低,而II型实验鱼则无明显变化,I型和II型实验鱼偏好游泳速度的差异可能是由于在饥饿条件下二者能量节约和游泳功能维持的策略不同。     

市售腌腊肉制品卫生质量调查研究

为了调查腌腊肉制品的卫生质量状况,试验采用随机抽样方法,对重庆北碚城区市售的香肠、腊肉进行了感官和亚硝酸盐残留的检验,并与家庭自制腌腊肉制品进行比较。结果表明:所检测的30份样品,其亚硝酸盐残留量均未超过国家限量标准;感官检查仅有一份样品为二级新鲜度,一级新鲜度样品所占比例为96.7%。