摄食促进物质对真鲷摄食和生长的影响

将甘氨酸 丙氨酸 组氨酸 精氨酸、甘氨酸 丙氨酸 组氨酸 精氨酸 甜菜碱、甘氨酸 丙氨酸 缬氨酸、甘氨酸 丙氨酸 缬氨酸 甜菜碱作为摄食促进物质，分别添加到真鲷配合饲料中饲喂真鲷，探讨摄食促进物质对真鲷摄食和生长的影响。结果表明，添加摄食促进物质不仅可促进真鲷的的摄食性，增加其摄食量，还可以提高真鲷的增重率、饲料效率、蛋白效率。添加甜菜碱对促进真鲷的摄食性无作用，但可促进真鲷的生长。     

饥饿对真鲷生长及生化组成的影响

在２０℃条件下，对真鲷进行了不同时间的饥饿处理后再投饵的恢复生长实验。饥饿１５ｄ的真鲷体重下降７．０５％，鱼体水分含量略有上升，蛋白质含量的比能值略有下降，脂肪含量和灰分含量没有明显改变。这表明真鲷在饥饿过程中主要消耗蛋白质作为身体的能量来源。分别给饥饿处理０（对照）、３、６、９、１２和１５ｄ的真鲷投饵，在饱足摄食的条件下生长２周。各饥饿处理组的鱼体生化组成及比能值均接近，并恢复到对照组水平。饥饿３、６ｄ处理组在恢复生长的特殊生长率、摄食率明显高于对照组，而食物转化率与对照组无显著差异；饥饿９、１２和１５ｄ处理组的特殊生长率和食物转化率均显著高于对照组，而摄食率与对照组无显著差异。结果表明真鲷幼鱼具有超补偿生长能力，短期饥饿的真鲷在恢复生长中通过显著提高摄食水平来达到补偿生长；而继续延长饥饿时间则通过显著提高食     

短蛸(Amphioctopus fangsiao)幼体摄食行为和不同饵料对其生长、存活的影响

为了研究短蛸(Amphioctopus fangsiao)不同生长阶段的饵料需求，本研究采用刚孵化的短蛸幼体作为实验材料，首先观察不同环境条件下短蛸幼体的摄食行为，然后通过投喂不同的饵料，对短蛸幼体的生长过程进行研究。结果显示，卤虫无节幼体密度从0.1个/ml上升至1个/ml的过程中，密度在0.1个/ml时短蛸初孵幼体摄食量高；1–2 d龄幼体和2–3 d龄幼体有较为强烈的摄食行为，因此，需要从孵化第2天开始重视短蛸幼体的饵料情况。晚上是初孵幼体的摄食活跃阶段，在室内光和黑暗条件下均表现出高摄食量。投喂混合饵料时，短蛸幼体有较高的存活率和增长率；初孵幼体(0.03 g)培育过程中，卤虫无节幼体是关键饵料；当幼体开始附底(0.1 g)时，应及时进行饵料转换，虾苗和贝肉是附底幼体的重要饵料。该研究结果对短蛸规模化苗种繁育具有重要实用价值。     

真鲷在饥饿后恢复生长中的生态转换效率

在２０℃条件下,对分别饥饿处理０（对照）、３、６、９、１２和１５d的真鲷进行了再 投饵的恢复生长实验。结果发现,饥饿３和６d的真鲷在恢复生长中的特殊生长率、摄食率 显著高于对照组,而生态转换效率与对照组,而摄食率与对照组无显著差异。这表明短期饥饿的真鲷通过显著提高摄食水平来达到补偿生长,继续延长饥饿时间则通过显著提高生态转换效率来达到补偿生长。作者认为,真鲷在饥饿后恢复生长中生态转换效率升高的机制可能     

日粮水平和饵料种类对真鲷能量收支的影响

以玉筋鱼为铒料生物,采用室内流水模拟实验法研究了摄食水平和饵料种类对真鲷能量收支各组分和能量收支分配模式的影响。结果表明,真鲷的生长量、总代谢量、排泄量及生态转换效率均随日粮水平升高呈减速增长趋势,二者之间的定量关系均可用对数曲线加以定量描述;不同生物饵料能造成真鲷摄食、生长、排泄和总代谢水平的显著差异,但却不能改变以比能值为单位的生态转换效率。依据各收支过程的量化结果,可得到真鲷的能量分配模式。     

短蛸(Amphioctopus fangsiao)幼体摄食行为和不同饵料对其生长、存活的影响

为了研究短蛸(Amphioctopus fangsiao)不同生长阶段的饵料需求,本研究采用刚孵化的短蛸幼体作为实验材料,首先观察不同环境条件下短蛸幼体的摄食行为,然后通过投喂不同的饵料,对短蛸幼体的生长过程进行研究。结果显示,卤虫无节幼体密度从0.1个/ml上升至1个/ml的过程中,密度在0.1个/ml时短蛸初孵幼体摄食量高;1–2 d龄幼体和2–3 d龄幼体有较为强烈的摄食行为,因此,需要从孵化第2天开始重视短蛸幼体的饵料情况。晚上是初孵幼体的摄食活跃阶段,在室内光和黑暗条件下均表现出高摄食量。投喂混合饵料时,短蛸幼体有较高的存活率和增长率;初孵幼体(0.03 g)培育过程中,卤虫无节幼体是关键饵料;当幼体开始附底(0.1 g)时,应及时进行饵料转换,虾苗和贝肉是附底幼体的重要饵料。该研究结果对短蛸规模化苗种繁育具有重要实用价值。     

投喂卤虫无节幼体条件下黄颡鱼仔稚鱼生长、存活率、摄食力和体成分的变化

试验分析了投喂卤虫无节幼体条件下黄颡鱼(Pseudogrus fulvidraco)仔稚鱼生长、存活率、摄食力和体成分的变化。随着仔稚鱼的生长和发育,摄食率和胃充塞度逐渐加大,体长大于10 mm的仔鱼,摄食率都在93.3%以上,大多数个体胃充塞度都在3～5级。投喂卤虫无节幼体的黄颡鱼仔稚鱼生长较传统育苗方式生长快,存活率高。体内粗养分、氨基酸与脂肪酸含量都发生相应变化。黄颡鱼淀粉酶、蛋白酶与脂肪酶活性均在1日龄时即可检测到,开口期即5日龄时,3种消化酶比活力均达到较高值,15日龄后消化酶比活力又都降低到较低水平。卤虫无节幼体体内营养物质含量丰富,大小适口,是黄颡鱼仔稚鱼开口摄食的优质生物饵料。     

摄食水平和饵料种类对3种海洋鱼类生长和生长效率的影响

采用室内流水模拟法测定了摄食水平与铒料生物种类对真鲷、黑鲷、黑Ｊｕｅ特定生长率和生长效率的影响。３种实验鱼类的物壹生长率均随摄食水平增大呈减速增长趋势。二者间的定量关系和对数曲线描述；而其生长效率则均随摄食水平增大呈倒“Ｕ”形变化趋势。二者间的定量关系可用二次曲线描述，曲线相关检验结果表明，其特定生长率和生长效率与摄食水平之间均呈显著相关关系。依据上述定量关系，分别求得３种鱼的维持摄食量和最佳摄食     

长江口疏浚土悬沙对中华绒螯蟹幼体发育和变态的影响↑（*）

长江口疏浚土悬沙对中华绒螯解蚤Ⅰ、蚤Ⅳ和大眼幼体发育和变态影响为：不同悬沙浓度对各期幼体成活率无显著影响,对蚤Ⅳ和大眼幼体的发育和变态亦无显著影响,但会推迟蚤１蜕皮变态。水体中的县沙对中华绒螯解蚤Ⅰ幼体生长和变态的影响与幼体此时的摄食习性（被动摄食）和摄食颗粒大小有关。     

真鲷幼鱼消化酶活性的昼夜变化

真鲷(Ｐａｇｒｏｓｏｍｕｓｍａｊｏｒ)是重要的海产经济鱼类,近年来已广泛开展养殖。但如何提高真鲷人工育苗成活率,已成为养殖生产的制约因素。有关真鲷育苗期的摄食强度、投喂时间和次数[郑微云等1993,1994],真鲷仔稚幼鱼摄食受光照的影响[李大勇等1994]已有少数报道。本文对真鲷幼鱼消化酶活性昼夜变化进行研究,以期对真鲷育苗期的合理投喂提供科学依据。1　材料与方法取同一批孵化后41日龄,长23±3ｍｍ的真鲷幼鱼,置于室温(12～14℃)下培养24ｈ。为了消除幼鱼饥饱程度对消化酶活性的影响,每2ｈ投喂龙头鱼(Ｈａｒｐｏｄｏｎｎｅｈｅｒｅ…     

舟山褐牙鲆（Paralichthys olivaceus）仔鱼摄食和生长的研究

试验研究了褐牙鲆Paralichthys olivaceus仔鱼的摄食和生长。结果表明，仔鱼初次开口摄食时间在6日龄（16～18℃），初次摄食率为30％，8日龄饥饿仔鱼最大初次摄食率为65％，孵出后第9天达到不可逆点（PNR），混合营养期为3d左右。初次摄食强度和初次摄食率开始时较低，在卵黄囊耗尽时达最高，然后下降。随着饥饿时间的延长，仔鱼出现“负增长”，孵化第11天存活率仅为10％，12日龄全部死亡。     

Lipid Nutrition and Feeding of Cobia Rachycentron canadum Larvae

This study examined the fatty acid composition of cobia Rachycentron canadum eggs and yolksac larvae, as well as the ovaries of wild caught females as an initial guide to lipid nutritional requirements. A 2-wk feeding study also was conducted to investigate the effectiveness of four dietary treatments on the growth and survival of cobia larvae. Cobia eggs in the tailbud stage contained 31.4 ± 1.3 μg lipid/egg. After hatching, the amount of lipid decreased significantly (P < 0.05) from 28.3 ± 0.3 to 23.2 ± 0.1 μg lipid/larvae during the yolksac larval stage (days 1 to 3 after hatching). Ovaries from wild caught adults and captive spawned eggs and yolksac larvae contained high levels of PUFAs with docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and arachidonic acid (ARA) accounting for approximately 80% of the total suggesting that cobia larvae may have a high dietary requirement for these fatty acids. For the feeding study, larvae were fed: 1) Artemia only; 2) enriched rotifers for 1 d only + microparticulate diet (day 313); 3) enriched rotifers for 3 d (day 3–5) + Artemia (day 3–13); and 4) enriched rotifers for 6 d (day 3–8) + Artemia (day 3–13). Cobia larvae began feeding on rotifers 3 d after hatching and on newly hatched Artemia nauplii by the fifth day following the onset of exogenous feeding (day 7). On day 7, no differences in larval growth were found among larvae fed rotifers for 3 versus 6 d, whereas larvae fed only Artemia or rotifers for I d followed by microparticulate diet were significantly smaller (P < 0.05) and did not survive beyond day 9 and 13, respectively. The results of the feeding study indicate that cobia larvae require rotifers for a minimum of 4 d following the onset of exogenous feeding.     

马拉瓜丽体鱼仔鱼饥饿试验及不可逆点的确定

在（28±1）℃条件下对马拉瓜丽体鱼（Cichlasoma managuense）仔鱼进行饥饿试验,确定仔鱼的不可逆点（PNR）,并研究延迟投饵对仔鱼成活和生长的影响。结果显示,仔鱼在4日龄时开口摄食,进入混合营养期,持续3 d;7日龄时卵黄囊消失,进入外源营养期。初次摄食率开始时仅为15%,6日龄时的初次摄食率最高达100%,9日龄以后初次摄食率急剧下降,PNR出现在仔鱼孵出后第9至第10日龄。延迟投饵1～3 d对仔鱼的成活率影响不大,延迟投饵4 d以上仔鱼成活率明显下降。完全饥饿条件下仔鱼全长在0～8日龄为正增长,之后开始转为负增长。延迟投饵1～3 d的12日龄仔鱼全长无显著差异（P〉0.05）;延迟投饵超过4 d的仔鱼全长则有极显著差异（P〈0.01）。马拉瓜丽体鱼仔鱼的最佳投喂时间应在仔鱼开口后的3 d之内。     

延迟投饵对真鲷,牙鲆仔鱼早期阶段摄食,存活及生长的影响

试验结果表明：（１）２日龄真鲷，牙鲆仔鱼初次摄食，在６￣７日龄和５￣６日龄，不能建立外源性营养的仔鱼分别进入ＰＮＲ期，而卵黄囊均在此前１￣２天已耗尽。混合营养期分别为３￣４天和１￣２天。（２）真鲷和牙鲆仔鱼在不同饥饰饿阶段初次摄食率的变化式型是：开始较低，此后逐步上升，高峰期出现在卵黄囊接近耗尽时，此后开始下降。记录到的最高初次摄食率分别为８６．７％和３５％。（３）牙鲆仔鱼体长的增长率随延迟投饵天     

The proteolytic digestive activity and growth during ontogeny of Parachromis dovii larvae (Pisces: Cichlidae) using two feeding protocols

The proteolytic digestive activity and growth of Parachromis dovii larvae during the ontogeny were evaluated in a recirculation system using two feeding strategies during a 28-day period. Larvae were reared using two feeding protocols (three replicates each): (A) Artemia nauplii (at satiation), fed from exogenous feeding [8 days after hatching (DAH)] until 15 DAH followed by nauplii substitution by formulated feed (20 % day^?1) until 20 DAH and then formulated feed until 28 DAH; (B) formulated feed (100 % BW daily) from exogenous feeding until 28 DAH. Levels of acid (pepsin type) and alkaline digestive proteases as well as growth and survival of larvae were measured along the feeding period. Survival was high and similar between treatments: 98.9 ± 0.0 for Artemia, 97.3 ± 0.0 % for formulated feed. The specific growth rate for length and weight was higher in larvae fed with Artemia nauplii than in larvae reared with formulated feed: 3.4 ± 0.1 versus 1.8 ± 0.1 % day^?1 for body length (P = 0.009) and 12.2 ± 0.1 versus 6.5 ± 0.3 % day^?1 for body weight (P = 0.002). The acid and alkaline proteolytic activity was detected, in both treatments, from the beginning of the experiment, at 8 DAH. The total enzymatic activity (U larva^?1) for acid and alkaline proteases was higher in larvae reared with Artemia after 12 DAH, whereas the specific enzymatic activity was similar for both enzyme types in the two treatments. The results suggest that P. dovii larvae were capable to digest formulated diets from the beginning of exogenous feeding and that they could be reared with formulated feeds. However, the formulated feed used should be nutritionally improved because of the poor growth obtained in this research.     

Fatty acid utilization during the early larval stages of Florida pompano (Trachinotus carolinus) and Common snook (Centropomus undecimalis)

The pattern of conservation and loss of fatty acids from the yolk sac during the endogenous feeding period and subsequent starvation was studied in pompano and snook larvae. Fundamental information on the early fatty acid dynamic and mobilization of pompano and snook larvae was collected. In both species, fatty acids were utilized as an energy source after hatching. Mono‐unsaturated fatty acids were catabolized, while saturated and poly‐unsaturated fatty acids were conserved. High levels of arachidonic acid (ARA) in pompano and snook eggs, as well as selective retention in the unfed larvae suggest a high dietary requirement for this fatty acid during the early stages of larval development. The effect of an ARA supplementation was therefore investigated in snook larvae at the rotifer feeding stage. The fatty acid profile of the larvae was successfully influenced to match that of wild eggs; however, no significant improvement in growth or survival was observed. Future research should be carried out over a longer period of time and include factors related to stress resistance.     

Mortality processes of hatchery‐reared Pacific bluefin tuna Thunnus orientalis (Temminck et Schlegel) larvae in relation to their piscivory

In mass culture of Pacific bluefin tuna Thunnus orientalis, yolk‐sac larvae of other species are fed as a major prey item to tuna larvae from 7 to 8 mm in total length. Marked growth variations in tuna larvae are frequently observed after feeding of yolk‐sac larvae, and this variation in the growth of tuna larvae is subsequently a factor leading to the prevalence of cannibalistic attacks. To elucidate details of the mortality process of hatchery‐reared tuna larvae after the initiation of yolk‐sac larvae feeding, we compared the nutritional and growth histories of the surviving (live) tuna larvae to those of the dead fish, found dead on the bottom of the tank, as direct evidence of their mortality processes. Cause of mortality of tuna larvae 3 and 5 days after the initiation of feeding of yolk‐sac larvae was assessed from nitrogen stable isotope and otolith microstructure analyses. Stable isotope analysis revealed that the live fish rapidly utilized prey fish larvae, but the dead fish had depended more on rotifers relative to the live fish 3 and 5 days after the initiation of feeding of yolk‐sac larvae. The growth histories based on otolith increments were compared between the live and dead tuna larvae and indicated that the live fish showed significantly faster growth histories than dead fish. Our results suggest that fast‐growing larvae at the onset of piscivory could survive in the mass culture tank of Pacific bluefin tuna and were characterized by growth‐selective mortality.     

不同温度、饵料对宽体金线蛭仔蛭生长和存活的影响

本文研究了不同温度和饵料对宽体金线蛭仔蛭生长和存活的影响。结果表明：宽体金线蛭（ Whitmania pigra）仔蛭在不同温度条件下的生长速度和存活率存在显著差异（ P /0.05）。在水温为27℃条件下,仔蛭生长速度最快、存活率最高;而33℃下的仔蛭存活率最低、生长最慢。投喂不同的饵料,仔蛭的生长速度和存活率也有显著的差异（ P /0.05）;投喂轮虫和圆田螺组的仔蛭生长速度最快、存活率最高;投喂蛋黄组的仔蛭存活率最低、生长速度最慢。     

延迟投饵对奥尼罗非鱼仔鱼摄食、生长和存活的影响

在盐度为5‰,水温(28±0.5)℃的条件下,对延迟投饵0~7d的奥尼罗非鱼(Oreochromis niloticus×O.aureus)仔鱼摄食、生长与存活进行了研究,并确定了仔鱼的饥饿不可逆点(PNR)。试验于仔鱼开口的当天开始试验。结果显示:仔鱼于3日龄开口;延迟投饵0~7 d组,投饵2 h后仔鱼摄食发生率分别为20%、100%、83.3%、36.7%、13.3%、6.7%、3.3%和0%,各组之间差异显著(P<0.05);延迟投饵在2 d以内,10日龄仔鱼体长和体重与对照组无显著差异(P>0.05),延迟投饵超过2 d,体长和体重显著低于对照组(P<0.05);奥尼罗非鱼仔鱼存活率随延迟投饵天数增加而降低,延迟0~2 d的10日龄仔鱼的存活率相差不大,介于78.6%~79.3%,各组差异不显著(P>0.05),延迟投饵超过2 d的仔鱼存活率较低,介于0%~33.3%;奥尼罗非鱼仔鱼的不可逆点出现在仔鱼开口后第4 d,开始投喂的最佳时间在仔鱼开口后的3 d之内。     

Growth and Feeding Level in Pre-Weaning Tambaqui Colossoma macropomurn Larvae

The relation between growth, feed utilization and feed ration was assessed during the first 15 feeding days in Colossoma macropomum larvae fed with Artemia nauplii. Maintenance, optimum and maximum feeding rations (1.23; 5.48 and 27.2% body weight/d, dry feed, respectively) and feed conversions (0.4 and 0.78 optimum and maximum, respectively) were determined. At maximum feeding the larvae grew 2.6 times faster that at optimum feeding, but the feeding costs increased 1.94 times. Two commonly used growth rates (specific growth rate, SGR and coefficient G) were compared for the modelling of larval growth. The maximum specific growth rate (SGR, growth rate at maximum feeding) remained relatively constant during the first 15 d of feeding and is thus much more adequate to model the growth of tambaqui larvae, than the coefficient G, which increased more than four times in this period.