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1.
盐度对鲻鱼前期仔鱼生长与存活的影响   总被引:5,自引:0,他引:5  
本文研究了鲻鱼前期仔鱼在不同海水盐度条件下的生长和存活情况。结果表明:鲻鱼前期仔鱼生长与存活的适宜盐度范围为20-32‰,盐度低于20‰,随盐度下降,前期仔鱼存活率降低,生长速度趋慢;反之,盐度高于32‰,随盐度升高,前期仔鱼存活率降低,生长速度趋缓。  相似文献   

2.
盐度变化对黑鲷幼鱼生长与存活的影响   总被引:1,自引:0,他引:1  
采用逐步降低或升高盐度(每天降或升2-2.5‰)的方法将黑鲷幼鱼淡化或成化,分别置于6‰、12‰、30‰(对照组)、55‰四个盐度组中饲养3个月。在6‰盐度组中,黑鲷幼鱼不能正常摄食与生长,存活率只有1.8%;在其余盐度组中,黑鲷幼鱼能正常摄食与生长,存活率都在50%以上,对照组成活率最高,为66.7%,其次是12‰盐度组,存活率为64%;在生长方面,对照组体长和体重增长率蕞高,其次分别是12‰、55‰、6‰盐度组。  相似文献   

3.
温度和盐度对大泷六线鱼仔鱼存活与生长的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
研究了温度和盐度变化对大泷六线鱼Hexagrammos otakii Jordan et Starks仔鱼存活与生长的影响.结果表明,大泷六线鱼初孵仔鱼及10日龄仔鱼在温度4~16℃范围内都能存活与生长,存活率均在84%以上,温度为20℃试验组的存活率均低于50%.盐度渐变条件下,盐度10~30范围内存活率都大于90%,在盐度为5及以下时仔鱼的存活率降为0,仔鱼对高盐度的适应能力较差.盐度突变条件下,盐度25和30的试验组仔鱼的存活率都在95%以上,盐度10~20的试验组仔鱼出现不同程度的死亡,存治率可达56%~75%.大泷六线鱼仔鱼的最适生长温度为12~16℃,最适生长盐度为25~30.  相似文献   

4.
盐度对九孔鲍摄食_生长及存活的影响   总被引:6,自引:0,他引:6  
陈昌生 《水产学报》2000,24(1):41-45
九孔鲍摄食人工饲料的盐度范围为20 ̄38,其中较适宜的盐度范围为25 ̄35,在此盐度范围内,小规格鲍(平均壳长1.30cm,平均体重0.37g)的壳长日增长为91.5 ̄102.3μm,日增重为8.60 ̄12.55mg;大规格鲍(平均壳长2.7cm,平均体重2.3g)的壳长日增长为56.30 ̄81.80μm,日增重为12.68 ̄22.48mg,其最适生长的盐度为30 ̄35,存活率为97% ̄100%。  相似文献   

5.
盐度对日本鬼鲉受精卵发育及仔鱼生长的影响   总被引:1,自引:0,他引:1  
研究了盐度对日本鬼鲉(Inimicus japonicus)受精卵发育及仔鱼生长的影响,并测定了仔鱼不投饵存活系数(SAI)。结果表明:(1)鬼蚰受精卵盐度在19—35均可孵化,最适盐度为27—31。盐度高于31,孵化率随盐度的升高而降低;盐度低于27,孵化率随盐度的下降而降低。(2)试验盐度范围内鬼铀仔鱼SM值为3.49~22.12,仔鱼生长和存活的最适盐度范围为23~27,适宜盐度范围为19—31。  相似文献   

6.
本文就盐度对漠斑牙鲆幼鱼的生长及存活的影响进行了探讨,结果表明:漠斑牙鲆幼鱼适宜盐度范围为0~36,最适盐度范围为6~18。在适宜盐度下,漠斑牙鲆幼鱼生长快,存活率高。过高或过低的盐度对幼鱼的生长发育均有一定的抑制作用。  相似文献   

7.
盐度对黄鲷胚胎发育及早期仔鱼生长的影响   总被引:16,自引:0,他引:16  
施兆鸿 《水产学报》2004,28(5):599-602
The effect of salinity on embryo and early larva development of Dentex tumiforns was discussed. Floating forms of egg in different salinities, optimal salinity for embryonic development and early larva growth was studied. The results showed: 1. In immobile condition, all eggs sank at salinity of 32.0, most of egg ssuspended in the middle of water at 34.0, and all eggs floated on the surface when salinity above 36.0. 2. Eggs did not hatch out at salinity of below 10.0 or above 60.0 and the death time of egg gradually moved up with increase or decline of salinity. Eggs hatched out at salinity range of 15.0 and 50.0, including abnormal larva. There was indistinct difference in speed of embryonic development (about 36-40h) within the salinity of 15.0 and 50.0. However the salinity had a great effect on larval survival after hatching and abnormal rate. The relation between hatching rate and salinity variation showed parabola but abnormal rate showed inverted parabola. The hatching rate was 81%-86% and abnormal rate of yolk sac larva was 27%-30% in suitable salinities of 27.0-39.0. The hatching rate was 89%-91% and abnormal rate was 13%-16% in optimal salinities of 33.0-36.0. The oil ball of abnormal larva was located in the central or front position. With increased extent of salinity, spondyle of larva bended and number of larva with arrhythmia increased. 3. The optimal salinities were 30.0-35.0 based on SAI. The test with SAI showed that SAI of early larvae was 41.25-47.53 at salinities of 30.0-35.0, the yolk and oil ball of 7-8 days larva was completely absorbed with a survival rate of 88%.  相似文献   

8.
盐度胁迫对遮目鱼幼鱼存活、生长及性状相关性的影响   总被引:1,自引:0,他引:1  
设置盐度梯度为0、10、20、27(自然海水)、35,共5个实验组,每组3个平行。遮目鱼(Chanos chanos)幼鱼不经过过渡直接放入各梯度盐度中,养殖30 d后统计存活率,测量每尾鱼的体质量及各表型形态性状,以体质量为因变量(y),各形态性状为自变量(x)进行通径分析和决定系数分析。结果表明,盐度0组的幼鱼存活率最低(73.33%),增重率(573.94±231.58)%和特定生长率(6.23±1.16)%最高,与其他组差异极显著(P0.01)。除盐度0组外,其他各组幼鱼的存活率均在90%以上,且幼鱼特定生长率和增重率在各组之间差异不显著(P0.05)。相关分析表明,幼鱼的各形态性状与其体重之间呈极显著的相关关系(P0.01)。通径分析表明,遮目鱼幼鱼的体长、全长和体高对体重的影响最大,且在不同盐度胁迫下对幼鱼体重的决定作用不同,其他性状对体重的影响较小。建立了盐度胁迫下形态性状对体重影响的最优回归方程。  相似文献   

9.
不同盐度对点斑蓝子鱼幼鱼生长、存活影响的研究   总被引:2,自引:0,他引:2  
在4m×5m×1.0m的室内水泥池中进行了0、5、10、15、20五种盐度(‰)条件下点斑蓝子鱼(Siganusguttatus)幼鱼的养殖试验,观察了不同盐度条件下点斑蓝子鱼幼鱼的存活率及生长效果。结果表明:经过30d养殖,环境盐度5-20苗池鱼苗的存活率为95%~99%,环境盐度为0(淡水)苗池的存活率为65%;各苗池鱼苗的尾增重均值分别为0.36g、0.56g、0.64g、0.65g和0.85g,增重倍率分别为50%、77%、88%、89%和117%;其中,盐度10—20苗池鱼苗的生长率差异不显著,盐度0与20苗池鱼苗的生长率差异显著。结果显示尽管篮子鱼具有广盐性特点,但10—20的培育盐度似乎更适合篮子鱼的生长。  相似文献   

10.
盐度对菲律宾蛤仔浮游幼体存活和生长的影响   总被引:8,自引:2,他引:8  
研究结果表明:菲律宾蛤仔受精卵在26℃水温下的最适孵化盐度为23 8~34 8,孵化率平均在80%以上;盐度38 3和21 2组,对受精卵的孵化有一定负面影响,孵化率为30%~60%;盐度低于15 9,受精卵基本上不能孵化;盐度29 5为幼体生长的最适盐度,8d可生长成下潜幼体,平均日生长16μm,成活率90%,盐度高于或低于29 5,其幼体的存活和生长都受到很大影响。  相似文献   

11.
The lined seahorse, Hippocampus erectus (Perry), is an important species in both medicinal and aquarium trades. The aim of this study was to evaluate the effects of stocking density (1, 3 and 5 individuals L−1) on the growth performance and survival of the early-stage juvenile H. erectus. The height (HT), wet weight, weight gain (WG) and specific growth rate (SGR) were affected significantly by the stocking density during the 40-day study. The HT, WG and SGR of the seahorse at 1 and 3 juveniles L−1 were significantly higher than that at 5 juveniles L−1. The survival of juveniles at the three stocking densities was not significantly different at day 25 (90.3 ± 4.5%, 86.7 ± 4.2% and 86.2 ± 3.8% for 1, 3 and 5 juveniles L−1 respectively), but was significantly different at day 40 (87.8 ± 3.9%, 69.6 ± 4.2% and 52.9 ± 2.8% for 1, 3 and 5 juveniles L−1 respectively). For the early-stage juvenile H. erectus, we recommend a stocking density of 3 juveniles L−1, but the density should be reduced to 1–2 juveniles L−1 to avoid reduced and variable growth and high mortality after 25 days.  相似文献   

12.
13.
The element zinc (Zn) can elicit a variety of physiological responses in animals, particularly through its effects on steroid hormone receptor expression. Here, we evaluated the effects of Zn on the expression profiles of steroid hormone receptors in the lined seahorse, Hippocampus erectus, following experimental acute and chronic Zn exposure. Complex response patterns were observed; however, steroid hormone receptor expression in liver and kidney following 12‐day Zn injection (acute exposure) differed significantly from the control treatments. Apparent effects on hepatic lipid metabolism and osmotic regulation in the kidney need detailed investigation. Furthermore, 49‐day (chronic) waterborne Zn exposure produced a significant decrease in both estrogen receptor (ER) expression levels and estradiol concentrations. In additional, chronic exposure led to a substantial reduction of hepatic adipose cells, implying that Zn may regulate hepatic lipid metabolism via ER and estradiol. Our study demonstrated the effects of both acute and chronic Zn exposure on expression patterns of steroid hormone receptors, which will contribute to understanding the mechanism of Zn‐induced hepatic lipid metabolism and other physiological responses in seahorses.  相似文献   

14.
The lined seahorse, Hippocampus erectus, is an Atlantic species, which mainly inhabits shallow sea beds or coral reefs. Seahorse has become very popular in China due to its wide use in traditional Chinese medicine (TCM). However, the aquaculture of the lined seahorse has been threatened by a variety of diseases, especially bacterial infections. Skin ulcer syndrome becomes more and more common in the culture of seahorses, leading to skin ulcer, liver erosion and minority tail rotting. These diseased seahorses die in only 72 hr, causing huge economic losses in aquaculture. Pathogen HMT‐1 was isolated from the lined seahorses with skin ulcer syndrome, which was identified as Vibrio harveyi. The median lethal dose (LD50) of HMT‐1 was 2.88 × 108 cfu/ml. The pathogenic mechanism of HMT‐1 was preliminarily studied, and the pathological changes of the diseased lined seahorses were also investigated. Moreover, the activities of ACP, complement 3, SOD and LZM at different time post injection were measured by commercial kits. Our findings can provide reliable reference for diagnosis and treatment in the future.  相似文献   

15.
16.
营养强化对灰海马幼体氨基酸组成的影响及品质的评价   总被引:1,自引:1,他引:1  
为评价复合营养型强化剂对灰海马(Hippocampus erectus)幼体氨基酸组成模式和营养品质的影响,用0.045 mL/L(A)、0.090 mL/L(B)和0.180 mL/L(C)3个浓度的50DE-微囊强化的卤虫投喂灰海马幼体。结果显示,灰海马氨基酸总量(TAA)的平均值为51.10%(质量分数,干样);灰海马含有17种氨基酸(AA),其中8种人体必需氨基酸总量(TEAA)占TAA比例的平均值为31.00%,4种呈味氨基酸总量(TDAA)占TAA的比例超过45.00%(质量分数,干样)。限制性氨基酸为异亮氨酸(Ile)和亮氨酸(Leu)。必需氨基酸指数(EAAI)的平均值为36.97。随着强化剂浓度升高,卤虫和灰海马体内部分AA、TAA、TDAA和非必需氨基酸(TNEAA)的含量及大多数单个必需氨基酸含量与必需氨基酸总量比值(A/E)均与强化剂浓度呈反比(P<0.05)。但是,卤虫和灰海马的TEAA/TAA和TEAA/TNEAA的值却随强化剂浓度升高而上升(P<0.05)。同时,从氨基酸评分(AAS)、化学评分(CS)和EAAI的评分模式可以看出,B、C两组灰海马的评分总体显著高于A组(P<0.05),但B、C两组间大部分氨基酸评分差异不显著(P>0.05)。结果说明,过高浓度的强化剂无法显著提高氨基酸的相对含量,但却能在一定程度上改善氨基酸的组成模式。  相似文献   

17.
黄永春  涂晨凌  翁虹雨  林祥日 《水产学报》2020,44(10):1637-1644
为研究生长缓慢海马的出现时间和生理特性,选取饲养110 d正常生长海马[(8.57±0.61) cm,(1.51±0.38) g]与生长缓慢海马[(6.68±0.35) cm,(0.81±0.14) g]进行生长、消化酶和免疫酶活性以及RNA/DNA研究。结果显示,当体长大于5.03 cm时,正常生长海马的生长速度明显大于生长缓慢的海马,正常生长海马的日均增重率、特定生长率、肥满度和脏体指数均优于生长缓慢海马。2种生长性状海马的消化酶(蛋白酶、淀粉酶和脂肪酶)活性在不同反应温度(5、15、25、30、35、45和55°C)和pH (2.0、3.0、4.0、5.0、6.0、7.0、8.0和9.0)条件下的变化趋势基本一致,正常海马消化酶均显著高于生长缓慢海马(除淀粉酶活性在35~55°C和蛋白酶在5~15°C外)。正常生长海马酸性磷酸酶、碱性磷酸酶、总抗氧化能力和过氧化物歧化酶活性分别比生长缓慢海马高12.83%、48.21%、44.71%和65.75%,且差异显著。正常生长海马丙二醛仅为生长缓慢海马的61.09%,且差异显著。另外,正常生长RNA/DNA值比生长缓慢海马高23.75%。...  相似文献   

18.
This investigation examined the effects of light intensity, stocking density and temperature on the air-bubble disease, survivorship and growth of early juveniles (2–30 days old) of seahorse Hippocampus erectus Perry. The juveniles in the 100 lx treatment had the highest air-bubble disease rate of 20.8 ± 6.2% and the juveniles in the 500 lx treatment had the highest survival rate of 84.4 ± 5.5%. The juvenile seahorses cultured in the 1500 lx treatment had the highest final wet weight of 0.13 ± 0.02 g and the highest final standard length of 4.54 ± 0.37 cm (F7, 144=57.406, F7, 144=12.315, P<0.05). There was no significant effect of stocking density on the air-bubble disease rate (F6, 21=1.893, P=0.126). The juveniles cultured in the 1 ind L−1 had the highest wet weight increment of 0.134 ± 0.031 g, but juveniles in the 2 ind L−1 had the highest standard length increment of 3.17 ± 0.30 cm (F6, 126=34.902, F6, 126=11.726, P<0.05), and juveniles cultured in the 1.5 ind L−1 had the highest survival rate of 86.1 ± 4.6%. The result of interaction of light intensity and temperature showed that the juveniles cultured in the 1500 lx and 26 °C had the highest weight gain and specific growth rate of 3791.17 ± 323.97% and 13.07 ± 0.18, respectively, and the lowest air-bubble disease rate of 9.3 ± 4.5% occurred in the 1000 lx and 26 °C (F8, 36=12.355, P<0.05).  相似文献   

19.
以枯草芽孢杆菌(Bacillus subtilis)、植物乳杆菌(Lactobacillus plantarum)和粪肠球菌(Enterococcus faecalis)为菌源,研究了不同配比复合益生菌对灰海马(Hippocampus erectus)幼苗养殖效果的影响。实验包括3个单菌处理和6个复合菌处理(3种菌1∶2∶3比例的随机组合),共9个加菌处理,另设无菌处理作为对照。用于评估养殖效果的指标包括:养殖水体菌群、幼苗特定存活率和生长率、幼苗肠道免疫指标(免疫球蛋白Ig M、白介素IL-1β、干扰素IFN-α和肿瘤坏死因子TNF-α)和肠道菌群。结果发现:加菌处理组中,其养殖水体均含有大量的目标益生菌,并且养殖水体的弧菌含量均显著低于对照组。幼苗存活率方面,除了D组(芽孢∶乳杆∶粪肠=1∶2∶3)、E组(芽孢∶乳杆∶粪肠=1∶3∶2)和F组(芽孢∶乳杆∶粪肠=2∶1∶3)的存活率显著低于对照组外,其他组存活率均显著高于对照组,其中G组(芽孢∶乳杆∶粪肠=2∶3∶1)和I组(芽孢∶乳杆∶粪肠=3∶2∶1)的存活率最高,均超过了65%。特定生长率除了B组(植物乳杆菌单菌处理)与E组外...  相似文献   

20.
This study assessed the effect of starvation on survival and nutritional status of newborn juveniles H. erectus (<10 days) to optimize rearing protocols, thereby helping to reduce wildlife exploitation. Maximum starvation time (MST) was estimated through the survival of juveniles continuously starved from birth. Resistance to starvation and the effect of food re‐introduction after 1, 2, 4 and 6 days of starvation on survival and metabolite concentrations (total proteins, total lipids, acylglycerides, cholesterol, glucose) were also determined. Survival amongst continuously starved animals decreased from 6.6 ± 0.5 to 0% from days 9 to 10 of starvation. Seahorses under different starvation–refeeding treatments all had 100% survival up to day 5 of experiments. After 10 days, however, a 4‐day starvation period followed by refeeding showed negative effects with <50% survival. During continuous starvation, lipids were the first energy reserve used to maintain basal metabolism, followed by proteins. Except for cholesterol, all metabolite concentrations differed between continuous starvations and feeding. Despite high seahorse survival after 5 days in the absence of food, the recovery of the metabolic status is possible after a starvation period of no more than 2 days, since irreversible physiological changes compromising the ultimate survival of the organisms take place after this time.  相似文献   

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