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1.
研究了温度、盐度和pH对圆斑星鲽精子活力的影响。结果表明,圆斑星鲽精子活力最适宜温度范围为8~12℃,最适宜盐度范围为25~35,最适宜pH范围为7~8。由实验结果可知,20℃以上高温和盐度15以下的低盐度海水对圆斑星鲽精子活力有抑制作用,在适宜环境条件下精子快速活动时间最长为7~8min,精子寿命最长为12~17min。生产操作中,圆斑星鲽人工受精应在适宜的环境条件下、精子活力高的时间内进行,以获取高质量的受精卵。  相似文献   

2.
在实验室条件下,初步研究了水温对东星斑幼鱼摄食、生长及存活的影响。温度设5个水平(15、20、25、30、35℃),东星斑幼鱼在玻璃蓄养槽内养殖40d。结果显示20℃组、25℃组和30℃组的鱼没有死亡,35℃组的存活率为88.9%,15℃组的存活率仅为50%;总摄食量在30℃组最高,15℃组最低;特定生长率在30℃组最高,15℃组、35℃组为负值;在可以生长的组别里,30℃组饵料系数最小。本研究表明,水温对东星斑幼鱼生长发育的影响明显,东星斑的适宜摄食温度为20~30℃,最佳摄食温度为25~30℃;水温<20℃东星斑幼鱼不能正常摄食、生长,甚至会死亡,水温15℃时,几乎不摄食;水温>30℃,东星斑幼鱼可以正常摄食,但是不能正常生长,甚至会死亡。  相似文献   

3.
在水温15~25℃下,将平均体质量分别为792?27±48?89 g(大)、513?49±39?19 g(中)和185?59±25?51 g (小)的圆斑星鲽(Verasper variegatus),按5?5 kg/m2和7?5 kg/m2的密度,饲养在5 m×5 m×3 m网箱中,投喂冰冻玉筋鱼60 d,以研究不同规格和密度的圆斑星鲽在网箱中的生长、饲料系数和体色变化情况。整个饲养期间,圆斑星鲽日增重变化在1?77~4?24 g/d,其中大规格鱼的日增重最高(3?49 g/d),当水温为15~20℃时,日增重可达4?24 g/d;饲料系数平均为4?87,其中大规格鱼的最低(4?16),当水温为15~20℃时,饲料系数为3?55;密度对圆斑星鲽网箱养殖的生长情况和饲料系数无显著影响;15~20℃时圆斑星鲽生长快于20~25℃时;网箱养殖圆斑星鲽体色逐渐接近野生鱼体色,无眼侧异常黑化的体色逐渐褪黑变白。研究认为,圆斑星鲽是一种适合网箱养殖的新品种。  相似文献   

4.
圆斑星鲽的生物学特性及养殖技术   总被引:2,自引:0,他引:2       下载免费PDF全文
从形态特征、生态习性和摄食习性等方面阐述了圆斑星鲽的生物学特性,并对其生长发育特点进行了简单介绍;重点阐述了圆斑星鲽的养殖技术,包括人工繁殖和饲养管理技术.  相似文献   

5.
水温对黄颡鱼摄食的影响   总被引:10,自引:0,他引:10  
本实验在不同温度下对黄颡鱼的摄食情况进行了观察。结果表明 :黄颡鱼在人工养殖条件下 ,水温对其摄食具有显著的影响。开始摄食水温为 11℃ ;较低温度下 ,黄颡鱼摄食率随温度升高而升高 ;当温度上升达到 2 9℃时 ,黄颡鱼摄食率随温度升高而下降。黄颡鱼的最适摄食率温度为 2 5~ 2 8℃ ,摄食率为 4 0 6~ 4 36 %。试验温度2 6℃时 ,获得最大摄食率 4 36 %。  相似文献   

6.
在室内流水条件下测定不同温度(15℃、20℃、25℃和30℃)对长吻Wei幼鱼摄食。生长及饲料转化效率的影响。结果表明:长吻Wei摄食与生长的起始温度为15℃;适宜温度区为20-30℃;最适温度为25℃左右。水温为10℃时,长吻Wei基本不摄食。水温为15-25℃时,长吻Wei摄食率 、生长率随永温升高而显著增加,25℃和30℃组间差异不大。饲料转化效率随水温上升明显提高,但水温升至30℃时,饲料  相似文献   

7.
日本对虾的温度适应性试验   总被引:3,自引:0,他引:3  
本试验分别以20℃、23℃、26℃、29℃、32℃、35℃六组水温对9cm左右日本对虾幼体温度适应性试验.根据对日本对虾幼体在不同水温条件下的增长率、增重率、存活率、脱皮率和摄食量的测定结果,总结出日本对虾在20℃~35℃温度范围内都能生长,适宜的生长温度为23℃~32℃,最适温度为23℃~29℃.  相似文献   

8.
在室内流水条件下测定不同温度(15℃、20℃、25℃和30℃)对长吻幼鱼摄食,生长及饲料转化效率的影响。结果表明:长吻摄食与生长的起始温度为15℃;适宜温度区为20—30℃;最适温度为25℃左右。水温为10℃时,长吻 基本不摄食,水温为15—25℃时,长吻摄食率、生长率随永温升高而显著增加,25℃和30℃组间差异不大。饲料转化效率随水温上升明显提高,但水温升至30℃时,饲料转化效率有下降的趋势。长吻幼鱼日投饵量可根据经验公式:C=0.148T ̄(1.626)W ̄(-0.521)计算。  相似文献   

9.
为了解工厂化养殖条件下圆斑星鲽(Verasper variegates)幼鱼的生长特性,在水温9.0~22.5℃时,对圆斑星鲽幼鱼的体长和体质量进行了近1年的测定分析。结果显示:平均体长为(9.29±0.16)cm、平均体质量为(22.11±1.03)g的5月龄左右的圆斑星鲽幼鱼,经1年的人工饲养后平均体长为(36.15±0.36)cm、平均体质量为(647.97±12.54)g,体长与日龄之间呈线性关系L=1.492x+2.350,R2=0.966,其体长平均瞬时增长率为0.12,体长平均月增长量为2.44 cm;体质量与日龄之间呈指数关系Wgc=9.380 e0.264x,R2=0.960,其体质量平均瞬时增长率为0.31,体质量平均月增长量为56.92 g;体长与体质量的回归曲线Wwl=0.030x2.971,R2=0967,幂指数约等于3,表明体质量与体长的立方呈正相关系,为等比生长类型。在工厂化养殖条件下,圆斑星鲽幼鱼的体质量增长量、体质量相对生长率、体质量瞬时生长率与水温变化大体一致,16~18℃时增重较快;反映幼鱼生长阶段的生长指标、生长系数波动较大,没有显示出规律性;体质量与体长呈显著相关,处于负异速生长阶段。  相似文献   

10.
圆斑星鲽的人工繁殖及育苗技术   总被引:6,自引:0,他引:6  
本文报道了圆斑星鲽的人工繁殖、育苗过程及结果,并比较了培育温度对仔、稚鱼生长和成活率的影响等。使用自然海区捕获的亲鱼,注射HCG,在水温14℃条件下,效应时间为24-28hrs。受精卵在水温14℃条件下,经94-96hrs孵出。仔鱼经55天培育,共培育出平均全长23.3mm的幼鱼5.5万尾,其成活率为18.3%。  相似文献   

11.
该研究通过肉眼观察、镜检,进行干露、饥饿、盐度突降、福尔马林等抗性试验,并采用病毒检测等方法,以期建立评估斑节对虾(Penaeus monodon)虾苗活力和质量标准。结果表明,斑节对虾健康虾苗具有趋光性、集群性,体表光洁,肌肉透亮,肠胃食物充盈等特性。测试虾苗干露时间以15min为宜,健康虾苗干露后能立即恢复活力,而病弱虾苗多出现死亡、昏迷现象;虾苗的成活率随饥饿时间的延长而降低,随福尔马林浓度升高和时间延长而降低,随盐度突降幅度增加而降低。健康虾苗能忍受100~200μL·L^-1福尔马林溶液30min,成活率近100%;在盐度20~30下虾苗的成活情况较好,而其在淡水中仅能存活1h。对虾苗进行病毒检测,可以避免养殖中因虾苗携带病毒而可能导致的病毒性疾病的暴发。  相似文献   

12.
鳟鱼发眼卵和旨种运输是养鳟生产的重要环节。发眼卵多在冬季和早春运输,苗种多在晚春和夏季运输。苗种运输大多以鱼篓充氧进行短距离汽车运输,长途运输冷水性鱼苗种的实例很少。本文总结了金鳟和虹鳟苗种长途运输方法,以期与养鳟业界共同交流提高。一、包装材料和方法内包装材料是苗种运输专用塑料袋,规格54×104cm,外包装是泡沫塑料箱,规格63.5×45.5×30.5cm,纸箱规格64×46×32.5cm。塑料袋采取双层式,内装苗种和水共12.5kg,其中苗种0.5-1.3kg,100-2000尾。起运前苗种停食1-2天。运鱼用水水温调至6℃,鱼、水入袋后袋内…  相似文献   

13.
猪的胎盘属于弥散型胎盘,这种胎盘的结构特点和饲养管理的不当,常常导致母猪胎衣不下发生,给生猪的生产繁殖带来极大损失。本文针对母猪胎衣不下发生病因、综合防治进行详细阐述,旨在对预防和治疗胎衣不下能有所帮助。  相似文献   

14.
The variation of virulence of Renibacterium salmoninarum , the causative agent of bacterial kidney disease (BKD) in salmonid fish, was studied by infecting rainbow trout, Oncorhynchus mykiss (Walbaum), with two isolates (strains 325 and 932) from diseased Atlantic salmon, Salmo salar L., and one isolate (strain 4366) from an apparently healthy Atlantic salmon. Coho salmon, Oncorhynchus kisutch (Walbaum), were injected with the strain 932 to estimate difference in fish species resistance. Fish were removed by random sampling for other study purposes, a study design possible with analysis of lifetime distributions incorporating both sampling-, death- and survival-times. At the end of the experiment, the rainbow trout infected with strains 325, 932 and 4366 had a survival probability of 33%, 51% and 72%, respectively. The coho salmon infected with strain 932 had a 26% survival probability. The strain differences were significant according to the log-rank test, and the risk ratio between the strains ranged from 1·8 to 5·4. The strain from the apparently healthy fish was least virulent. The survival of the fish species was different over time. Rainbow trout were more likely to die early in the time course, but high numbers of coho died later, resulting in an overall risk of mortality of 1·4 in favour of rainbow trout. Differences in virulence may reflect changed selective pressure on R. salmoninarum when introduced from feral stocks into the environment of fish farms.  相似文献   

15.
《水生生物资源》2003,16(5):461-465
Anti-proteinase activity was demonstrated in the seminal plasma of cyprinid fish species (bream, chub, ide, dace, asp, goldfish, roach, common carp) using electrophoretic techniques combined with a detection method based on inhibition of bovine trypsin. We found species-specific protease inhibitors in the seminal plasma of cyprinids. At least three bands of protease inhibitors with different migration rates could be identified by native PAGE. Higher variability was characterized for bands with slower migration rates. Visualization of inhibitors after SDS-PAGE under non-reducing conditions allowed estimation of their molecular weights. Apparent molecular weights were within the range of 51–59 and 47–54 kDa for the bands with slower and moderate migration rates, respectively. The molecular weight of fast migration bands for roach and common carp were estimated to 23 and 30 kDa, respectively. Inhibitors of common carp seminal plasma differed in their affinity toward serine proteases. Three inhibitors in common carp seminal plasma could be visualized using cod and bovine trypsin, but only two inhibitors (of high molecular weight) were recognized with chymotrypsin. There were differences in anti-proteinase activity and seminal plasma protein concentration in relation to the origin of common carp seminal plasma (breeding lines) and time of milt collection (spawning vs. post-spawning season).  相似文献   

16.
水硬度对七彩神仙鱼幼鱼发育的影响   总被引:4,自引:0,他引:4  
采用不同硬度的水对七彩神仙鱼幼鱼进行饲养。6周龄幼鱼在硬度为7.94°dH±0.30°dH时饲养84d后,比在硬度为14.71°dH±0.23°dH水中的幼鱼个体大,生长速度快。表明较高硬度的水有利于七彩神仙鱼幼鱼的生长发育。  相似文献   

17.
研究了不同年龄组(3~8龄)细鳞鱼(Bachymystax lenok Pallas)亲鱼的繁育效果,分析其繁育主要技术,包括亲鱼培育、繁育技术、受精卵孵化、鱼苗培育等,结果发现,5~6龄和7~8龄细鳞鱼产卵量没有明显差异,产卵量、孵化率、出苗率均较高,繁殖效果明显好于3~4龄亲鱼。  相似文献   

18.
黄志 《现代渔业信息》2006,21(9):18-20,30
在分析海口市海洋渔业资源和海洋捕捞现状的基础上,提出了近海渔业资源衰退的6项原因和加快保护和修复资源的10项措施和建议。  相似文献   

19.
虎斑乌贼受精卵卵黄营养成分分析   总被引:3,自引:3,他引:0  
本实验对虎斑乌贼受精卵卵黄的营养成分进行分析,旨在探讨其幼体的营养需求量,为其幼体配合饲料研制提供参考数据。随机选取大约800个虎斑乌贼受精卵的卵黄,采用国家标准方法测定其水分、灰分、粗蛋白质、粗脂肪、氨基酸、脂肪酸和矿物元素含量。结果表明:1)虎斑乌贼受精卵卵黄中粗蛋白质含量为76.33%(干重基础);总氨基酸(TAA)和必需氨基酸(EAA)含量分别为71.22%和32.38%(干重基础),EAA/TAA为45.46%,氨基酸中以谷氨酸(Glu)含量最高(9.97%),必需氨基酸中亮氨酸(Leu)含量最高(7.58%)。2)其粗脂肪含量12.71%(干重基础);共检出17种脂肪酸,包括8种饱和脂肪酸(SFA)、5种单不饱和脂肪酸(MUFA)和4种多不饱和脂肪酸(PUFA),SFA、MUFA和PUFA分别占脂肪酸总量的43.47%、7.54%和49.25%,其中以DHA含量最高,达32.80%,EPA含量为7.70%,DHA/EPA为4.26。3)检测出Na、K、Ca、Mg、Sr、Mn、Fe、Cu、Zn、Al和As 矿物元素,微量元素中富含Zn、Al和Fe,含量分别为 0.77、0.71和0.43 mg/kg(鲜重基础)。由此可见,卵黄具有高蛋白、低脂肪,富含n-3PUFA的特点;虎斑乌贼幼体饲料中蛋白质需求量参考值为76.33%;氨基酸需求量参考值,如赖氨酸(Lys)为5.49%,蛋氨酸(Met)为2.63%;脂肪的需求量参考值为12.71%,DHA为4.17%,EPA为0.98%;微量元素需求量参考值,如Zn为2.77 mg/kg,Cu为0.19 mg/kg(干重基础)。  相似文献   

20.
Air-breathing fishes have evolved bimodal respiratory mechanisms for exploitation of water (through gills and highly vascularized skin) as well as atmospheric air (through aerial respiratory organs, ABO). Mucous cells in these respiratory organs of variously stressed fishes exhibit periodic fluctuations in their density and staining properties. The main types of damage in the gills include congestion of blood capillaries (BLCs), periodic lifting and sloughing of respiratory epithelia of the secondary lamellae causing haemorrhage, extensive fusion of secondary lamellae and hyperplasia of the respiratory epithelia due to uncontrolled regeneration leading to asphyxiation, altered excretion, and death of the fish. Haemolysis has also been observed following lead exposure. The damage in the ABO of Heteropneustes fossilis includes sloughing of the epithelial cells, leading to haemorrhage causing decreased red blood corpuscles density and degeneration of the secondary gill lamellae with reduced respiratory area. Subsequent hyperplasia of the respiratory epithelia and fusion of gill lamellae increase the respiratory barrier distance. The BLCs often bulge out and protrude into the lumen, bringing blood nearer to air. The ladder-like pillar cell (PLC)-BLC components of the gill lamellae frequently collapse. Damage to the ABO of Channa striata is less severe. Often haemorrhaging due to bursting of extensively stretched BLCs causes aerial respiratory failure. Chloride cells of the ABOs also show hyperplasia. While the highly mucogenic epidermis of C. striata shows less damage, the epidermis of Clarias batrachus and H. fossilis shows severe wear and tear, sloughing, and haemorrhage. Side-by-side regeneration continues, causing altered histomorphology of the epidermis. The different gland cells also show periodic fluctuations in their density and staining. The dermis also shows severe damage with loosening of their connective tissue fibres. These fibres give stronger reactions for sulfated mucin that not only retain additional water molecules for continuance of skin breathing, but also bind the toxic ambient pollutants.  相似文献   

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