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尖裸鲤(Oxygymnocypris stewartii)成熟卵呈圆形,黄色,沉性,卵径(2.57±0.07)mm,受精卵吸水充分膨胀后卵径为(3.22±0.07)mm。水温9.5～11.8℃,尖裸鲤胚胎发育历时265h,根据胚胎发育的外部形态及典型特征,将其分为受精卵、胚盘形成、卵裂、囊胚、原肠、神经胚、器官分化和孵化共8个阶段、32个时期。出膜仔鱼全长(10.27±0.15)mm,出膜20d后卵黄耗尽,全长(15.22±0.27)mm。出膜后80d,鱼苗全长(23.65±0.59)mm,臀鳞出现,各鳍均已出现,鱼苗侧线全部形成且清晰,体色和体型接近成鱼。尖裸鲤早期发育的特点反映了其对雅鲁藏布江水域的适应性。报道了尖裸鲤胚胎发育和仔稚鱼发育的生物学特性,为雅鲁藏布江特有鱼类资源保护利用提供科学依据和理论基础。 相似文献
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研究硬刺松潘裸鲤(Gymnocypris potanini firmispinatus)早期生活史阶段的发育规律,为松潘裸鲤的亚种分化研究、规模化人工繁殖和苗种培育提供理论依据。松潘裸鲤亲鱼采自雅砻江支流安宁河流域。雌鱼6~13龄,全长12.1~24.2cm,体重16.1~115.8g;雄鱼3~9龄,全长8.2~14.5cm,体重5.2~23.8g。结果显示,硬刺松潘裸鲤受精卵呈圆形,黄色,卵径(2.82±0.10)mm;水温(16±1)℃下,硬刺松潘裸鲤的胚胎发育历时183h45min,胚胎发育过程分为受精卵、胚盘形成、卵裂、囊胚、原肠、神经胚、器官分化和出膜共8个阶段、31个时期;出膜仔鱼全长(7.82±0.19)mm;出膜10d后,仔鱼的鳃、口、胸鳍、尾鳍、鳔、肠道等功能器官先后形成;出膜13d后卵黄囊消失,全长(14.33±0.51)mm;出膜40d后各鳍基本长成,体型和体色接近成鱼,进入幼鱼阶段。硬刺松潘裸鲤为地区重要的小型经济鱼类,主要分布在雅砻江中游各大干支流中,在形态和生态上形成一系列的适应性,早期发育过程与其栖息的环境同样具有一定的适应性。 相似文献
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2016年4月1日—4月19日,在水温12～14℃下采用催产、人工授精和室内孵化方式获得暂养的野生新疆裸重唇鱼Gymnodiptychus dybowskii受精卵和仔鱼,观察其胚胎发育和早期仔鱼的形态特征。结果显示:新疆裸重唇鱼成熟鱼卵为亮黄色或橙色,卵径(2.2±0.28)mm,受精约35min后卵周隙达到最大,卵径2.90～3.40mm,卵黄约占卵体积的3/5。整个发育过程可分为受精卵、卵裂期、囊胚期、原肠胚期、神经胚期和器官形成期6个阶段。在水温(16±2)℃下,胚胎发育积温为2 359h·℃,187h仔鱼上浮。研究结果表明,新疆裸重唇鱼的胚胎发育特征与新疆地区其他几种裂腹鱼类存在一定差异。 相似文献
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《福建水产》2015,(6)
在(24±1)℃温度条件下观察长丰鲢(Changfeng silver carp)受精卵发育过程及其胚胎发育各个时期的形态特征。结果显示:长丰鲢受精卵为漂流性卵(半浮性卵),无油球,细胞质均匀分布,卵径为(1.55±0.05)mm,吸水后卵膜膨大,卵径达到(5.10±0.40)mm。在水温(24±1)℃的条件下,胚胎发育总历时为(28.5±1.0)h,胚胎发育过程所需总积温为(685.0±62.3)℃獉h。长丰鲢受精卵卵裂方式与其他家鱼一样,属于盘状卵裂,本文依据胚胎发育各阶段的形态特征,将其划分为7个连续发育的关键阶段,18个不同的时期,分别为受精卵期、卵裂期、囊胚期、原肠胚期、神经胚期、器官发生期和出膜期。 相似文献
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采捕野生拟目乌贼进行室内培育,利用显微成像系统观察其胚胎发育过程.结果表明,拟目乌贼受精卵乳白色,半透明,呈椭圆形,乳头状,一端呈圆环状套住附卵基质,如葡萄般成串有规律地聚集一起.刚产出的受精卵长径为(39.7±1.7) mm,短径为(17.1±1.1) mm,体质量为(4.3±0.2)g.胚胎呈椭圆形,长径(8.85±0.41) mm,短径为(7.74±0.54) mm.在水温为27℃,盐度为30条件下,孵化第10天卵粒变得最小,长径为(27.2±0.6) mm,短径为(13.3±0.6)mm,体质量为(2.02±0.02)g.第11天后受精卵开始膨大,孵化前受精卵长径为(32.7±0.8) mm,短径为(19.3±0.6)mm,体质量为(4.68±0.02)g.胚胎发育分为11个阶段:受精卵期、卵裂期、囊胚期、原肠胚期、胚体形成期、器官形成期、红珠期、心跳出现期、色素出现期、内骨骼形成期和孵化期.胚胎发育历时20 d,初孵乌贼胴长(8.1±0.2)mm,胴宽(6.1±0.2) mm,体质量(0.18 ±0.02)g. 相似文献
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黄河裸裂尻鱼胚胎发育和双头鱼形态初步观察 总被引：1，自引：0，他引：1
采用观察法和描述法对黄河裸裂尻鱼胚胎发育进行试验研究。黄河裸裂尻鱼成熟卵卵径(2.3±0.1)mm,卵为淡黄色、微粘性,吸水后失去粘性;受精卵在(16.5±0.7)℃下历时约165 h20 min,经过卵裂阶段、囊胚阶段、原肠胚阶段、器官发生阶段、出膜阶段等一系列过程孵化出膜。初孵仔鱼全长(10.1±0.2)mm。128细胞期开始出现卵黄运动,随后运动加剧,但在器官发生阶段不明显。1尾雌鱼孵化出的1.4万尾仔鱼中有约1.1万尾为双头。双头鱼有3种形态,发育至第21天全部死亡。 相似文献
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通过干法授精获得乌原鲤受精卵,对其胚胎发育全过程进行连续观察。结果显示,乌原鲤成熟卵子呈圆球形、亮黄色、具黏性,卵径1.68~1.98mm,吸水膨胀后卵径2.28~2.57mm。水温(20±1)℃时,受精卵至出膜时长为80.8h,积温1616.0℃·h。乌原鲤胚胎发育与其他鱼类胚胎发育过程相似,历经受精卵、卵裂、囊胚、原肠胚、神经胚、器官形成至出膜6阶段,各发育阶段所需积温分别为44.4、136.0、127.0、130.2、55.0、1123.4℃·h。出膜阶段历时47.45h,初孵仔鱼自尾部破膜孵出,全长约6.10mm,体高1.60mm。温度对乌原鲤胚胎发育及出膜阶段影响明显,水温(20±1)℃比水温(15±1)℃胚胎仔鱼出膜时间更早、出膜更同步、出膜时段更集中。 相似文献
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通过对人工网箱养殖4年的斑鱾(Girella punctata Gray)亲鱼进行LHRH-A3激素催产,获得自然产卵的受精卵,于实验室中进行培育孵化,连续观察斑鱾胚胎发育的全过程。实验结果表明,斑鱾受精卵呈圆形,卵径0.882±0.041 mm、卵黄直径0.807±0.036 mm,具1个圆形油球,油球径为0.266±0.023 mm。在孵化水温23±0.5℃、盐度33.8条件下历时28 h 20 min完成整个胚胎发育过程,初孵仔鱼全长1.574±0.109mm。胚胎发育过程可划分为6个阶段,即受精卵、卵裂期、囊胚期、原肠胚期、神经胚期和器官形成期,包括27个发育时期。实验旨在了解斑鱾的胚胎发育规律,为开展斑鱾的人工繁殖提供基础资料。 相似文献
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Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean 
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下载免费PDF全文 The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna. 相似文献
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Cardiac,ventilatory and metabolic responses of two ecologically dissimilar species of fish to waterborne cyanide 总被引：1，自引：0，他引：1
Changes in heart rate, ventilatory activity and oxygen consumption were determined in trout (Salmo gairdneri) and brown bullhead catfish (Ictalurus nebulosus) during exposure to a steadily increasing concentration of waterborne cyanide selected to produce death in 8–9 hours for each species. The lethal cyanide concentration for the bullheads was an order of magnitude higher than for trout. Trout developed an immediate and gradually increasing bradycardia throughout the exposure period. Cyanide produced tachycardia in the bullhead followed by a gradual onset of bradycardia as the concentration of cyanide was raised. Pericardial injection of atropine (a muscarinic cholinergic antagonist) indicated that bradycardia in the trout was due initially to increased vagal tone but later due to the direct effect of cyanide on the heart. Hyperventilation in the trout persisted throughout the exposure period, although the rate and amplitude fluctuated and was variable between individual fish. During the last hour of exposure (highest cyanide concentration), ventilation was characterized by rapid, shallow breaths followed by a sudden respiratory arrest. The bullheads exhibited hyperventilation during the first 3 hours of exposure followed by a gradual, linear drop in ventilation rate and amplitude until death occurred. Cardiac and ventilatory responses in both species were attributed to stimulation of central and peripheral chemoreceptors by cyanide. Evidence is presented which suggests the initial response in the bullheads was due, at least in part, to gustatory stimulation by the cyanide. Oxygen consumption of the trout remained above pre-exposure levels for the majority of the test period. Oxygen consumption in the bullhead paralleled the changes in heart and ventilatory rates. Whole-body lactate levels of fingerlings of both species during cyanide exposure were measured to estimate the extent of anaerobiosis. Whole-body lactate levels were much greater in the bullheads than the trout, indicating a higher capacity for anaerobiosis, possibly due to a greater fuel supply. Overall, the trout responded to cyanide in a manner similar to that produced by environmental hypoxia whereas the bullheads experienced a gustatory stimulus which masked the hypoxia-like response. 相似文献
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Effects of a mix of Bacillus sp. as a potential probiotic for Florida pompano,common snook and red drum larvae performances and digestive enzyme activities 下载免费PDF全文
下载免费PDF全文 M.R. Hauville J.L. Zambonino‐Infante J. Gordon Bell H. Migaud K.L. Main 《Aquaculture Nutrition》2016,22(1):51-60
This study examined the effect of a commercial mix of Bacillus sp. on survival, growth and digestive enzyme activities of Florida pompano, red drum and common snook. Larvae were fed either live feed enriched with Algamac 3050 (Control), Algamac 3050 and probiotics (PB), or the previous diet combined with a daily addition of probiotics to the tank water (PB+). Survival was not affected by the treatments for any of the species. At the end of the pompano and snook trial, standard lengths of larvae from the PB and PB+ treatments were significantly greater than for the control larvae. Microbiological analyses were performed at the end of the pompano trial, and numbers of presumptive Vibrio were not a concern in the system. For both pompano and snook, trypsin‐specific activity was higher in PB and PB+ larvae compared with the control larvae. Similarly, alkaline phosphatase activity was higher for the pompano larvae fed the PB and PB+ treatments and for the snook larvae fed the PB+ treatment compared with the control larvae. This experiment suggests that a mix of Bacillus sp. can promote growth through an early maturation of the digestive system during the early larval stages of pompano and snook. 相似文献
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We examined the element pattern in the otoliths of a migratory fish species that inhabit the coastal areas in the brackish of the Baltic Sea. The northern pike (Esox lucius) show migratory behaviour, spawning in streams and rivers and foraging in the sea. We examined spawning migration in four nearby streams in the south‐west part of the Baltic. Otolith analysis by microPIXE revealed unique elemental patterns (Sr, Zn, Br, Co and Mn) for the juveniles in each of the different streams. The strontium signal in the otolith of the juveniles was used as an indicator of freshwater origin and the time spent in the stream. Adult pike in their migrating spawning phase were caught in each of the streams. The elemental composition in otoliths in their freshwater phase (using juvenile pike in the streams as references) was determined. A principal component analysis showed that the elemental fingerprint during the freshwater phase several years back in time was similar for the adult fish and for juveniles inhabiting the stream today. The results indicated natal homing of the adults to a specific stream, a conclusion that was strengthened by the fact that marked fish returned to spawn over consecutive years. Anadromous pike in the Baltic Sea may thus be divided in subpopulations. The results of the study may have implications for fishery management, as pike in the Baltic Sea cannot be seen as homogenous population. 相似文献
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Studies of epidermal papillomatosis in fish populations have only rarely focused on the intensity of the disease, i.e. the number and size of papillomas. Furthermore, the methods used to evaluate the intensity of papillomatosis have not been standardized. We tested the reliability of a method based on counting of scales covered by papilloma tumours in roach, Rutilus rutilus (L). In addition, we studied the frequency distributions of the number of scales covered by papillomas within populations, evaluated the correlation between the prevalence and mean intensity of the disease among populations and examined the intensity of papillomatosis in roach with respect to sex and size of fish. Reliability of the scale coverage method was high. Therefore, the method could offer an effective way to determine the intensity of papillomatosis in fish species with large scales. The frequency distribution of the scale coverage of papillomas was highly aggregated within all populations studied. The mean intensity of papillomatosis increased with the size of the fish and was higher in males than in females. However, there was no correlation between the mean intensity and prevalence of the disease among the 19 roach populations studied. 相似文献
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P.-A. WOLD K. HOEHNE-REITAN C.L. CAHU J.Z. INFANTE J. RAINUZZO & E. KJØRSVIK 《Aquaculture Nutrition》2009,15(1):73-84
The aim of the present study was to compare effects of dietary n-3 highly unsaturated fatty acids (HUFA) being incorporated in the phospholipid (PL) or in the neutral lipid (NL) fraction of the larval feed, on larval growth and histology of digestive organs in Atlantic cod ( Gadus morhua L.) larvae. Three isoproteic and isolipidic diets, labelled according to the percentage of n-3 docosahexaenoic acid and eicosapentaenoic acid contained in NL1 or in PL1 and PL3 of the diets, were fed to cod larvae from 17 days post hatching (dph) to 45 dph.
In the liver, hepatocytes and their nuclei were smaller in NL1 larvae compared with the PL larvae; the mitochondrial membrane structures were less dense and the amount of lipids observed in the liver was significantly higher in NL1 larvae compared with the PL3 larvae. The liver and gut size was related to larval size, with no differences between the larval groups. The results demonstrated that the essential fatty acids were more beneficial for cod larvae when they were incorporated in the dietary polar PL rather than in the NL, and that the n-3 HUFA requirements in cod larvae is possibly higher than that in the PL1 diet. 相似文献
In the liver, hepatocytes and their nuclei were smaller in NL1 larvae compared with the PL larvae; the mitochondrial membrane structures were less dense and the amount of lipids observed in the liver was significantly higher in NL1 larvae compared with the PL3 larvae. The liver and gut size was related to larval size, with no differences between the larval groups. The results demonstrated that the essential fatty acids were more beneficial for cod larvae when they were incorporated in the dietary polar PL rather than in the NL, and that the n-3 HUFA requirements in cod larvae is possibly higher than that in the PL1 diet. 相似文献
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D.R. Tocher M. Agaba N. Hastings J.G. Bell J.R. Dick A.J. Teale 《Fish physiology and biochemistry》2001,24(4):309-320
The desaturation and elongation of [1-14C]18:3n-3 was investigated in hepatocytes of the tropical warm freshwater species, zebrafish (Danio rerio) and Nile tilapia (Oreochromis niloticus). The hepatocyte fatty acid desaturation/elongation pathway was assayed before and after the fish were fed two experimental
diets, a control diet containing fish oil (FO) and a diet containing vegetable oil (VO; a blend of olive, linseed and high
oleic acid sunflower oils) for 10 weeks. The VO diet was formulated to provide 1% each of 18:2n-6 and 18:3n-3, and so satisfy
the possible EFA requirements of zebrafish and tilapia. At the end of the dietary trial, the lipid and fatty acid composition
was determined in whole zebrafish, and liver, white muscle and brain of tilapia. Both zebrafish and tilapia expressed a hepatocyte
fatty acid desaturation/elongation pattern consistent with them being freshwater and planktonivorous fish. The data also showed
that hepatic fatty acid desaturation/elongation was nutritionally regulated with the activities being higher in fish fed the
VO diet compared to fish fed the FO diet. In zebrafish, the main effect of the VO diet was increased fatty acid Δ6 desaturase
activity resulting in the production of significantly more 18:4n-3 compared to fish fed the FO diet. In tilapia, all activities
in the pathway were greater in fish fed the VO diet resulting in increased amounts of all fatty acids in the pathway, but
primarily eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3). However, the fatty acid compositional
data indicated that despite increased activity, desaturation of 18:3n-3 was insufficient to maintain tissue proportions of
EPA and DHA in fish fed the VO diet at the same level as in fish fed the FO diet. Practically, these results indicate that
manipulation of tilapia diets in commercial culture in response to the declining global fish oil market would have important
consequences for fish fatty acid composition and the health of consumers. Scientifically, zebrafish and tilapia, both the
subject of active genome mapping projects, could be useful models for studies of lipid and fatty acid metabolism at a molecular
biological and genetic level.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Somayeh Torabi Delshad Siyavash Soltanian Hassan Sharifiyazdi Peter Bossier 《Journal of fish diseases》2019,42(4):477-487
In this study, we evaluated the impact of the catecholamines on growth, swimming motility, biofilm formation and some virulence factors activities of pathogenic Yersinia ruckeri. Norepinephrine and dopamine (at 100 µM) significantly increased the growth of Y. ruckeri in culture media containing serum. An increase in swimming motility of the pathogen was found following the exposure to the hormones; however, no effect was seen on caseinase, phospholipase and haemolysin productions. Further, antagonists for the catecholamine receptors were observed to block some of the influences of the catecholamines. Indeed, the effects of catecholamines were inhibited by chlorpromazine (the dopaminergic receptor antagonist) for dopamine, labetalol (α‐and β‐adrenergic receptor antagonist) and phenoxybenzamine (the α‐adrenergic receptor antagonist) for norepinephrine, but propranolol (the β‐adrenergic receptor antagonist) showed no effect. Pretreatment of Y. ruckeri with the catecholamines resulted in a significant enhancement of its virulence towards rainbow trout and the antagonists could neutralize the effect of the stress hormones in vivo. In summary, our results show that the catecholamines increase the virulence of Y. ruckeri which is pathogenic to trout through increasing the motility, biofilm formation and growth. 相似文献