光照强度对暗纹东方鲀稚鱼摄食的影响

在0～1000lx光照范围内,对不同光照强度下暗纹东方鲀稚鱼摄食量进行了测定,稚鱼在500lx时摄食强度最大,其次为300、700lx,摄食率在500lx时最高,并在5min时达到最大值,40～60min时段摄食效率最低接近停食。     

光照对细鳞裂腹鱼受精卵孵化率及仔鱼生长、摄食的影响

研究光照对细鳞裂腹鱼胚胎孵化及20日龄内仔鱼生长、摄食的影响,探讨了细鳞裂腹鱼胚胎及仔鱼所需的适宜光照条件,为该鱼的基础生物学研究积累资料,也为人工繁殖和养殖生产提供参考。仔鱼为人工育苗池中随机抽取的初孵仔鱼,仔鱼饵料为小球藻和鲜酵母混合培育的褶皱臂尾轮虫。水源为天然河水,试验期间水温16.0~18.0℃、溶解氧6.8~8.5 mg/L、pH 6.5~6.8,采用三基色节能荧光灯为暗室内光源。结果表明,在10~360 lx范围内,随着光照强度的增加,孵化率逐渐升高,300~360 lx时达到最高的孵化率88.1%,此后孵化率随着光照强度的增大又有所下降,细鳞裂腹鱼受精卵孵化适宜的光照强度为300~720 lx。光照对细鳞裂腹鱼仔鱼的生长及摄食有显著影响。12日龄后的仔鱼在40~60 lx光照强度下生长最好、摄食强度最大,400~600 lx次之;此后随着光照强度的增大,摄食强度又显著下降。在40~6 000 lx范围内随光照强度的增强,摄食强度下降,生长则变差。黑暗条件下的仔鱼摄食强度和摄食率最低,生长接近停滞,在15日龄时全部死亡。细鳞裂腹鱼仔鱼在20日龄以内的适宜光照强度为40~600 lx。     

不同光照强度下鹦鹉螺的行为观察

由于鹦鹉螺(Nautilus pompilius)物种及构造的特殊性,在动物进化及科普教育多方面具有重要的研究价值。对人工养殖条件下鹦鹉螺对不同光照度的行为适应性进行研究。实验设定4个光照梯度(Ⅰ~Ⅳ),各梯度光照分别为:50 lx、200 lx、350 lx和450 lx,各梯度实验时间分别为1个月,并测定缸体25个不同位点照度,通过观察鹦鹉螺体态与行为变化,了解照度对鹦鹉螺行为的影响。结果显示:1)实验各照度下鹦鹉螺体态、吸附、游动及进食行为正常;2)各照度梯度未连续出现不吸附现象及灯光反应现象,第Ⅲ和第Ⅳ光照梯度两类现象出现频次增加,灯光反应现象有显著差异(P0.05);3)随着照度增加,生长速度呈加快趋势;4)各照度梯度鹦鹉螺在缸体内各泳层及位点均有分布,分布最适照度范围依次为4.70~12.18 lx、15.39~58.90 lx、31.90~125.00 lx和42.35~75.00 lx。结果表明,实验各光照度对鹦鹉螺体态行为无明显影响,鹦鹉螺的最适光照上限为125 lx。     

漠斑牙鲆仔鱼摄食节律的研究

在实验室条件下研究了漠斑牙鲆仔鱼摄食节律。试验结果表明：漠斑牙鲆仔鱼摄食具有昼夜节律性，其摄食活动主要在白天进行，在10：00光照度为400lx时摄食最为活跃，抵达摄食高峰，仔鱼夜间不摄食，全天表现明显的摄食节律。     

长江口中华绒螯蟹雌蟹的食性和摄食强度

2017年10月-2018年4月逐月采集长江口生殖洄游期中华绒螯蟹(Eriocheir sinensis)雌蟹,运用胃含物分析法分析雌蟹抱卵前后饵料组成、摄食强度以及营养级,探讨其在长江口抱卵繁殖期间的摄食规律。结果表明:雌蟹摄食率、食物饱满指数、平均胃饱满度系数等3项指标具有明显的月份变动,抱卵前雌蟹的摄食指标在10-11月份(秋季)最高,12-2月份(冬季)最低;抱卵后雌蟹的摄食指标在12-2月份(冬季)最低,3-4月份(春季)最高。洄游期的雌蟹抱卵前后饵料来源多样,包括水生植物、藻类、甲壳类、多毛类、鱼类、软体动物、棘皮动物、卵、颗粒碎屑等。其中,藻类、颗粒碎屑和甲壳类为抱卵前的主要饵料,出现频率分别为68.13%、54.76%和19.05%;藻类、颗粒碎屑和水生植物为抱卵后的主要饵料,出现频率分别为70.35%、73.91%和25.39%。雌蟹抱卵前后饵料组成存在显著差异(χ^2=21.57,P<0.05),对差异贡献最大的饵料组成是颗粒碎屑(χ^2=8.32)、甲壳类(χ^2=5.49)和水生植物(χ^2=4.02)。雌蟹抱卵前后的营养级分别为3.60和3.10,平均营养级为3.35,属于第三营养级动物。     

暗纹东方鲀仔鱼早期发育阶段摄食和行为的研究

研究结果表明:1.在4－10日龄内,暗纺东方Hun(Takifugu obscurus)仔鱼摄取的蛋黄颗粒越来越大,4日龄仔鱼对粒径0.125-0.260mm的蛋黄颗粒的摄食率最高,10日龄仔鱼以0.191-0.309mm的为最高。2.6-10日龄仔鱼的摄食率在光照400－3000lx的范围内以1000－2000lx为最好,但没有显著影响。3.3日龄仔鱼以间歇式巡游为主,至7日龄才建立起完全的巡游模式。4.仔鱼摄食行为的发育分为较明显的两个阶段：一是前期仔鱼的前冲摄食,二是后期仔鱼身体呈现“L”攻击型和“咬食攻击型”的姿势摄食;12日龄之后,饥饿仔鱼的摄食反应次数明显低于正常仔鱼。     

不同光照强度对红鳍东方鲀稚鱼摄食的影响

为研究不同光照强度对红鳍东方鲀(Takifugu rubripes)稚鱼摄食的影响,试验测量了红鳍东方鲀在不同光照强度下的摄食量。结果表明,在400 lx时红鳍东方鲀稚鱼摄食量达到最高,随着光照强度的降低,在1 000～400 lx时,摄食量总体呈现出上升趋势;在400～100 lx时,摄食量呈现出下降趋势。在400 lx时,摄食率和摄食效率均随时间延长逐渐下降;在1 000、700、100 lx时,随着时间的延长摄食率和摄食效率均呈现出先上升后下降的趋势,最大值均出现在40 min。     

暗纹东方鲀仔鱼早期发育阶段摄食和行为的研究

研究结果表明 :1.在 4～ 10日龄内 ,暗纹东方 ( Takifugu obscurus)仔鱼摄取的蛋黄颗粒越来越大 ,4日龄仔鱼对粒径 0 .12 5～ 0 .2 60 mm的蛋黄颗粒的摄食率最高 ,10日龄仔鱼以0 .191～ 0 .30 9mm的为最高。2 .6～ 10日龄仔鱼的摄食率在光照 4 0 0～ 30 0 0 lx的范围内以 10 0 0～ 2 0 0 0 lx为最好 ,但没有显著影响。 3.3日龄仔鱼以间歇式巡游为主 ,至 7日龄才建立起完全的巡游模式。 4 .仔鱼摄食行为的发育分为较明显的两个阶段 :一是前期仔鱼的前冲摄食 ,二是后期仔鱼身体呈现“L”攻击型和“咬食攻击型”的姿势摄食 ;12日龄之后 ,饥饿仔鱼的摄食反应次数明显低于正常仔鱼     

东海外海绿鳍马面纯摄食习性的研究

1．东海外海的绿鳍马面魨是一种主食浮游甲壳类，兼食软体动物和珊瑚的杂食性鱼类。2．1-6月绿鳍马面魨摄食强度有两次高峰，分别出现在2-3月和5月。4月摄食强度最低，这可能和产卵习性有关。产卵前和产卵后均大量摄食，而在产卵盛期则少食或不食。3．绿鳍马面纯的摄食强度以南部鱼群为最高，中部鱼群次之，北部鱼群最低。饵料种类组成也不一样，北部鱼群主要是摄食浮游甲壳类，而南部和中部鱼群除摄食浮游甲壳类外还摄食不少珊瑚、角贝和扁卷螺。4．绿鳍马面魨-昼夜内，主要在下午到上半夜摄食，而在下半夜到上午则较少摄食和暂停摄食，明显地有昼夜垂直移动现象，产生此现象，不仅仅是由于追食饵料生物所引起，主要与其本身生活习性有关。     

深水网箱养殖黑鲷配合饲料的初步研究

黑鲷(Sparus macrocephallus Brasilewsky)，又名黑立、青郎，属暖温性底层鱼类，主要分布于北太平洋西部，其食性杂，摄食凶猛，不仅适合沿岸内湾池塘与网箱专养，还可与温和性鱼类搭配养殖。黑鲷的生长最适水温在22-28℃，一般网箱每立方米水体养殖密度在10千克左右，即一水体在1500米^3的深水网箱放养2万-3万尾。     

光照强度对人工养殖的山女鳟幼鱼生长性能的影响

在水温12.1～13.9°C下和直径80 cm、高60 cm,水深40 cm的圆形选育缸中研究了不同光照强度(1200lx、600 lx和300 lx)对平均体质量为10.10±0.8g的山女鳟(Oncorhynchus masou masou)幼鱼生长和存活的影响。结果表明,光照强度显著影响山女鳟幼鱼特定生长率(SGR)、肥满度(CF)和变异系数(CV)(P<0.01),高光照强度组SGR和CF值显著高于两个低光照强度组,而CV值则是高光照强度组显著低于两个低光照强度组;高光照强度组摄食率(FI)明显高于两个低光照强度组。实验表明,适度增强光照强度有利于山女鳟幼鱼的生长,这对于优化山女鳟幼鱼培育条件具有指导意义。     

光照强度对香溪河水华类型影响的模拟实验

探究光照强度对小球藻生长的影响,为香溪河水华预测提供理论依据。小球藻藻种为香溪河河水中平板分裂后逐步纯化所得。培养箱为40 L的方形塑料箱,四周用遮光布严实包裹。培养液30 L。培养液为用放置24 h后的自来水稀释25倍后的BG-11标准培养基,磷浓度0.285 mg/L,氮浓度9.48 mg/L,p H值7.3~7.8。恒温加热棒控制水温24℃。以平行布置的8根日光灯管作为光源,开关不同数量的日光灯管设定光强梯度,光照梯度为0、800、1 500、2 400、3 200、4 500、6 000 lx。采用电磁式真空泵曝气,曝气比率设置为10%。设置2组平行实验,每个培养箱中加入处理后的藻液10 m L。实验过程为期12d,每天上午8∶00取样,监测指标为光密度、叶绿素a、溶解性总磷、溶解性总氮。结果表明,光照强度在800~1 500 lx时易发生长周期的绿藻水华,绿藻水华转变为蓝藻水华的可能性低;3 200~4 500 lx时易发生短周期的绿藻水华;6 000 lx时发生蓝藻水华的风险很大。香溪河在光照强度小于3 200 lx时不必做蓝藻水华防御措施;光照强度大于4 500 lx时,需提前做适当的蓝藻水华防御措施。     

Effect of light intensity on self-feeding of rainbow trout <Emphasis Type="Italic">Oncorhynchus mykiss</Emphasis> reared individually

The self-feeding abilities of individually reared rainbow trout Oncorhynchus mykiss were investigated under four different light intensities (7×10⁻², 1×10°, 5×10¹, and 7×10² lx). There was no significant effect of light intensity on self-feeder learning ability and food wastage (which did not exceed 0.5%). However, there was high individual variability in the ability irrespective of light intensity. The total number of trigger actuations was significantly higher at 1×10° lx than at 7×10⁻² and 5×10¹ lx. Feeding patterns during the light phase of a day were classified as early or late in relation to the timing of significant peaks in fish feeding, or non-steady. The last pattern was defined when significant peaks were not observed. Under 7×10⁻², 1×10°, or 7×10² lx, a non-steady feeding pattern was the most common. Early feeding appeared only under the 1×10° lx regime with the random pattern, while the late pattern was observed under 7×10⁻², 5×10¹, and 7×10² lx. Under 5×10¹ lx regime half of the fish fed in the afternoon. These results suggest that light intensity can affect the timing of feeding judged from the frequency of pulling bite tags, but does not affect waste or learning period.     

The effect of light intensity on first feeding of the spotted sand bass Paralabrax maculatofasciatus (Steindachner) larvae

The effects of light intensity on feeding incidence and prey consumption at first feeding of spotted sand bass larvae (Paralabrax maculatofasciatus Steindachner), using four light intensity treatments (0, 100, 400, and 700 lx) were evaluated. Specimens were fed the rotifer Brachionus plicatilis at a density of 3 rotifers mL^?1. One hour after the addition of prey, 30±3 (mean±SEM) larvae were sampled from each treatment aquarium. Feeding incidence was evaluated as the percentage of larvae with prey in the digestive tract. Feeding intensity was measured as the number of prey in the digestive tract of the larvae. Histological analysis was carried out to describe the eye structure at the time of first feeding. Larvae fed in darkness (0 lx) had a significantly lower (P<0.05) feeding incidence (1.2±2.2%) and intensity (0.4±0.7 rotifers larvae^?1) than those larvae fed at 100 (28±11%, 1.8±0.2 rotifers larvae^?1), 400 (48±10%, 2.4±0.3 rotifers larvae^?1), and 700 lx (52±4%, 2.4±0.1 rotifers larvae^?1). Feeding incidence of the spotted sand bass larvae increased with light intensity while the feeding intensity showed no significant difference (P>0.05) between light treatments. Histological analysis of the eye structure showed that first feeding larvae had well‐formed lens along with a retina composed of pure single cones as photoreceptors.     

Light intensity preference of juvenile pikeperch Sander lucioperca (L.)

Light intensity preference of the pikeperch was tested in 1‐m² tanks divided into four lateral compartments with a hole in the middle to allow the fish to move between compartments. Two experiments were carried out with both 0+ and 1+ pikeperch: one testing intensities from 25 to 300 lx and the other from 1 to 50 lx. Light preference was observed individually for 5 days at 8, 11, 14 and 17 h. On the first and fifth day, the preference was tested without differences in light intensity (control). In both experiments, both age groups showed preference for the lowest available light intensity. Preference for low light intensity in pikeperch may be related to innate activity and feeding behaviour and to avoidance of harmful effects of light. It is suggested that under aquaculture operations, pikeperch should be reared under very dim conditions.     

Influence of light intensity on feeding, growth, and early survival of leopard coral grouper (Plectropomus leopardus) larvae under mass-scale rearing conditions

This study investigated the effect of different light intensities on feeding, growth and survival of early stage leopard coral grouper Plectropomus leopardus larvae. Four different light intensities (0, 500, 1000 and 3000 lx) were used and larvae were kept under constant light conditions from 0 day after hatching (DAH) to 5 DAH. The larvae were fed a small S-type of Thai strain rotifers at a density of 20 individuals/mL from 2 DAH. The number of rotifers in larval digestive organ and total length of larvae were examined at 3 h intervals between 04:00 and 22:00 h on 3 DAH, and thereafter at 6 h intervals until the end of the experiment (5 DAH). Four experimental trials of the larval rearing were repeated using by 60 kL mass-scale rearing tanks. The results indicate that coral grouper larvae are visual feeders and their food intake increases with increasing light intensity. Food intake of larvae reared at 3000 lx was significantly higher than those reared at 0–1000 lx on 3 DAH despite being the first-feeding day (P < 0.01). On 4 DAH, total length of larvae reared at 3000 lx was significantly larger than those reared at the lower light intensities (0, 500 and 1000 lx), and thereafter light intensity significantly influenced larval feeding and growth until the end of the experiment. Survival on 5 DAH did not show a significant difference between light intensities, but survival rate at 3000 lx and 1000 lx had a tendency to be higher than those reared at the lower light intensities (0 and 500 lx). In contrast, larvae reared at 0 lx exhibited stagnant and/or negative growth. These results indicate that light intensity is significantly the factor affecting larval feeding, growth, and survival in coral grouper larvae under the rearing conditions.     

温度、光照强度对舌状蜈蚣藻早期发育的影响

舌状蜈蚣藻（Grateloupia livida）是一种具有较高应用价值的红藻。文章研究了不同的温度（15℃、20℃、25℃和30℃）和光照强度（500 lx、2500 lx、5 000 lx和10 000 lx）对舌状蜈蚣藻早期发育的影响。试验结果表明,舌状蜈蚣藻适合果孢子发育为盘状体的条件为温度25℃、光照5 000 lx。果孢子在25~30℃条件下首先形成盘状体,15℃下形成最慢;盘状体在25℃首先长出直立枝,其次是20℃、15℃和30℃。果孢子在5 000~10 000 lx的光照强度下首先形成盘状体,2 500 lx次之;在盘状体发育过程中较高光强可以促进盘状体的生长发育,低光强培养条件显著抑制了盘状体的生长发育。     

光照度对海月水母螅状体存活和生长的影响

研究了不同光照度对海月水母螅状体存活及生长的影响。试验结果表明,光照对海月水母螅状体存活和生长的影响显著。在光照度1200、800、400、0lx条件下,各组螅状体柄径生长与时间的回归方程式分别为y=0.003842x+0.345;y=0.003722x+0.313;y=0.004623x+0.317;y=0.006608x+0.303,经检验相关显著或极为显著。     

艾比湖卤虫滞育诱导的临界光周期和感知光照度的研究

卤虫具有滞育模式(卵生)和非滞育模式(卵胎生)两种繁殖模式,而光周期可能是影响其繁殖模式的重要的环境因子,因此明确其临界光周期和感知光照度对于有效地调控卤虫滞育、繁殖等将具有重要实践意义。本研究在实验室条件下研究了艾比湖卤虫的临界光周期和感知光照度,结果表明,在常规养殖盐度(80)和温度(25℃)条件下,艾比湖卤虫的光反应曲线与典型的长日照反应型滞育昆虫类似,在非极端光周期下,艾比湖卤虫的临界光暗时长为(8.38±0.37)h,相应的临界日长为15.62h;在极端光周期下,24h光暗时长,滞育率为(32.42±6.70)%,极显著低于邻近长光暗时长滞育率(P0.01);0h光暗时长,滞育率为(19.01±5.98)%,较邻近短光暗时长滞育率略高,但差异不显著(P0.05)。感知光照度试验表明,艾比湖卤虫感知光照度可能处于10~50lx。本研究为卤虫的滞育诱导和繁殖模式的光控化养殖提供了重要的科学基础。