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1.
糙海参胚胎和幼体发育的形态观察   总被引：1，自引：1，他引：0  
为提高糙海参育苗技术,研究描述了糙海参从受精卵发育到稚参的形态变化,在显微镜下测定了受精卵、胚胎和幼体的大小,确定了糙海参胚胎发育的过程。结果表明,通过利用阴干、流水刺激法对成熟亲参进行人工催产,得到大量的受精卵,其受精率为90%以上。糙海参胚胎和幼体发育可分为受精卵、卵裂期、囊胚期、旋转囊胚期、原肠期、初耳状幼体、中耳状幼体、大耳状幼体、樽形幼体和稚参等阶段;在平均水温29℃,平均盐度34条件下,糙海参受精卵经3 h发育形成囊胚,4 h进入旋转囊胚期,5 h进入原肠期,19 h完成胚胎发育变态为耳状幼体;并经过7 d的生长与发育进入樽形幼体;第15天变态为稚参。观察发现,多精入卵现象则会导致胚胎发育不正常,最终使胚胎发育停止并死亡。在糙海参幼体发育过程中,大耳状幼体期幼虫臂的大小及其球状体的形成均可作为判断其幼体发育健康状况的重要指标:幼虫臂越大,球状体出现率越高,其幼虫的变态率和成活率也越高。对比发现,位于糙海参尾部的突出结构——尾突,为仿刺参和新西兰刺参所没有,这一结构差异同时导致了其骨片位置也不同;并且,糙海参胚胎和幼体与其他种类的海参在发育时间上存在一定差异。  相似文献   

2.
王冲  孙同秋  国俭文  张凯  尹琳琳 《水产科技情报》2019,46(4):196-200, 205
为提高刺参育苗技术,通过人工催产,对黄河三角洲地区养殖刺参的胚胎和幼体发育过程进行了研究,观察了刺参从受精卵发育到稚参的形态变化,在显微镜下测定了受精卵、胚胎和幼体的大小。试验结果:利用阴干流水刺激法对成熟亲参进行人工催产,其受精率达95%以上;在水温22℃、盐度30、pH 7.8的条件下,受精卵经7～9 h发育成囊胚,12 h进入旋转囊胚期,22 h进入原肠期,42～48 h完成胚胎发育,变态为耳状幼体,经10 d的生长发育进入樽形幼体期,经16 d变态为稚参。结果表明,刺参幼体的健康状况与其水体腔和胃部的生长发育状况密切相关,水体腔和胃部发育良好,有利于幼体的变态,提高存活率。  相似文献   

3.
为提高花刺参育苗技术,对花刺参自受精卵发育到稚参的形态变化进行了观察研究,详细描述了胚胎发育各个时期的形态特征。通过阴干、流水刺激法对成熟亲参进行人工催产,得到大量的受精卵。在水温27~30℃及盐度33.0~35.0室内水泥池进行花刺参幼体培育。花刺参受精卵经5h发育成囊胚,7h进入旋转囊胚期,9h进入原肠期,31h完成胚胎发育变态为耳状幼体,并经10d的生长发育进入樽形幼体,第20d变态为稚参。由结果可知,花刺参的幼体的健康状况与其水体腔和胃部生长发育状况密切相关,水体腔和胃部发育良好,花刺参的健康状况则佳,有利于幼体的变态与存活。  相似文献   

4.
仇磊  姜国良 《齐鲁渔业》2006,23(6):33-34
刺参(Stichopus japonicus)属于楯手目(Aspido- chirota)、刺参科(Stichopodidae)、刺参属(stichopus)。刺参有明显的变态生活史,由受精卵卵裂经囊胚期→原肠期→小耳状幼虫→中耳状幼虫→大耳状幼虫→樽形幼虫→五触手幼虫→稚参→幼参→成参(廖玉麟, 2001)。其中小耳状幼体、中耳状幼体、大耳状幼体统称为耳状幼体。耳状幼体是刺参整个生命周期中短暂而唯一的一个浮游生活阶段,幼体浮游一般需10天左右,之后变态为樽形幼体改为底栖生活,浮游时期幼体  相似文献   

5.
该试验研究了蚂蚁岛海域周围水质环境因子和刺参(Apostichopus japonicus)浮游幼体的发育过程、丰度以及分布情况,结果表明:刺参浮游幼体的生长发育周期大约为15 d,大致变态过程可分为:受精卵—囊胚期—原肠期—小耳状幼体—中耳状幼体—大耳状幼体—樽形幼体—五触手幼体—稚参;刺参浮游幼体总丰度的最大值为每立方米8 756.50个;刺参浮游幼体的平均丰度为每立方米139.86～327.35个;东、西蚂蚁岛南部海域刺参浮游幼体明显高于北部。  相似文献   

6.
为摸清黄河三角洲地区刺参繁育特性,提高刺参育苗技术,在显微镜下观察、测量了胚胎和幼体的大小及胚胎发育过程。结果表明,在水温22±0.5℃,盐度(30±0.5)‰、pH 7.8条件下,利用阴干、流水刺激法可成功进行人工催产。受精卵经42h完成胚胎发育变态为初耳状幼体,7d左右发育为大耳状幼体,体长为760.0~970.0μm;10d左右生长发育为樽形幼体,16d变态为稚参。  相似文献   

7.
为探讨温度胁迫对刺参基因表达的影响,从已构建的刺参耐寒基因筛选cDNA文库中选取差异基因主要卵黄蛋白(major yolk protein,MYP):MYP1和MYP2,利用实时荧光定量PCR研究了其在刺参胚胎发生和个体发育9个阶段(受精卵、囊胚期、原肠期、小耳状幼体、中耳幼体、大耳幼体、樽形幼体、五触手幼体和稚参)、成体7种组织(呼吸树、体腔液、肠、纵肌、体壁、雄性性腺和雌性性腺)、长时温度胁迫(20℃、4℃,30 d)和低温短时胁迫(7℃、4℃、1℃、-2℃,12 h)成体肠组织中的表达量。结果发现,MYP1和MYP2表达模式基本相同:(1)在胚胎发育阶段樽形幼体时期开始表达,随后的阶段持续表达,到稚参阶段表达量最高;(2)在7种组织中,肠中的表达量最高,在体腔液中基本不表达,其余组织中均有表达;(3)在长时(30 d)温度胁迫下,肠组织中MYP表达量由高到低依次为4℃、12℃、20℃,且在4℃的表达量为20℃的6倍左右;(4)在低温短时胁迫(1℃、-2℃,12 h)条件下,肠组织中MYP表达量受到显著抑制,约为常温条件下的一半。研究表明,MYP在刺参胚胎发育的樽形幼体阶段开始合成,成体合成部位主要为肠,水温过低会抑制其表达。  相似文献   

8.
唐黎  王吉桥  许重  程骏驰 《水产科学》2007,26(5):275-277
测定了刺参耳状幼体、樽形幼体、五触手幼体、稚参、3种规格幼参和成参[体质量分别为(82.349±1.532)g、(147.639±2.031)g和(179.866±1.609)g]消化道中蛋白酶、淀粉酶、褐藻酸酶和纤维素酶的活性。试验结果表明,耳状幼体至樽形幼体蛋白酶活力下降,之后,快速上升。稚参蛋白酶活性显著高于幼体。相反,从耳状幼体至稚参,淀粉酶的活力逐渐升高,至稚参达最大值。幼体期褐藻酸酶逐渐上升,至五触手幼体达峰值,然后下降,稚参降至最小值。幼体纤维素酶活性一直很低,变化不大,但稚参的纤维素酶活性增强。幼参和成参的蛋白酶和淀粉酶活力随着个体发育而逐渐上升,而褐藻酸酶的活性却随着个体的生长而缓慢下降,稚参达最小值。成体的纤维素酶活性低而稳。4种消化酶中,蛋白酶活力最高,纤维素酶最低。  相似文献   

9.
通过构建仿刺参cDNA文库,获得铁蛋白全长cDNA序列。该基因序列全长792 bp,5′非翻译区长133 bp,开放阅读框长522 bp,编码173个氨基酸,3′UTR长137 bp;预测蛋白分子量为20 ku。5′UTR具有一个高度保守的铁离子应答元件。仿刺参ferritin氨基酸序列具备脊椎动物ferritin的亚铁氧化酶活性中心所特有的保守结构。该序列与海参的同源性最高,达84%,与其它无脊椎动物如:海星、鲍、牡蛎、海葵、线虫、小龙虾和果蝇的同源性为74%~34%;与脊椎动物ferritin重链亚基同源性高于轻链亚基。系统进化分析表明,仿刺参的ferritin与大部分无脊椎动物聚为一支。利用半定量RT-PCR检测,ferritin mRNA在仿刺参未受精卵、受精卵、多细胞期、囊胚期、原肠期、小耳状幼体、中耳状幼体、大耳状幼体、樽型幼体、五触手幼体、稚参11个发育阶段和幼参的体壁、体腔细胞、肠道和呼吸树中均表达。Quantitative real-time PCR结果显示, ferritin mRNA在未受精卵至原肠期表达量低,从小耳状幼体至稚参表达量显著增高;在幼参的不同组织中,ferritin mRNA在呼吸树中的表达量显著低于其他3种组织;幼参注射LPS后,4种组织中ferritin mRNA表达量与注射前无显著差异。  相似文献   

10.
刺参樽形幼虫是刺参发育过程中继耳状幼虫以后的一个变态期。刺参在进入樽形幼虫期后,原来的纤毛运动逐渐减弱。个体的活动能力也因此而逐渐减弱。个体由原来的浮游生活逐渐过渡到底栖生活,这一时期由于幼体  相似文献   

11.
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   

12.
Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China.  相似文献   

13.
In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg.  相似文献   

14.
Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL?1 (1.25 ng well?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation.  相似文献   

15.
Tetrahymena is a protozoan parasite, which infects guppy, Poecilia reticulata Peters, and causes substantial economical losses in commercial farms worldwide. Studies of guppy infected by Tetrahymena require standardized infection protocols. The LD50 for Tetrahymena infection of guppies by intraperitoneal (IP) injection was calibrated, and the level obtained was 946 parasites per fish. Guppy infection with Tetrahymena by immersion, imitating the natural route of infection via the integument, was studied under normal or stress conditions. Exposure to cold and netting (CNI) and to cold only (CI) followed by immersion exposure to 10 000 Tetrahymena per mL resulted in 22.5% and 19.2% mortality, respectively, as compared to 14.2% and 10% in groups that were netted only (NI) or non‐stressed (I). Histopathology revealed that immersion infection resulted in a systemic infection. Lysozyme levels, measured 3 weeks after infection, were significantly higher in the CNI group (288 μg per mg protein) compared with CI‐, NI‐ and I‐treated groups (94.5, 64 and 62.3 μg mg?1, respectively). There was no evident parasite immobilization activity in body homogenates, suggesting no development of acquired immunity. Re‐infection by IP injection revealed no increase in protection in any of the treatment groups, mortality range of 56.3–75%, higher than in the non‐exposed control (40.6% mortality).  相似文献   

16.
Plasma estradiol-17 (E2), testosterone (T), 17,20-dihydroxy-4-pregnen-3-one (DHP) and 17,20,21-tri-hydroxy-4-pregnen-3-one (20-S) levels were measured by radioimmunoassay (RIA) in white perch (Morone americana) and white bass (M. chrysops) that were induced to undergo final oocyte maturation (FOM) with human chorionic gonadotropin (hCG). Plasma DHP levels increased in females of both species in association with oocyte germinal vesicle migration (GVM) and germinal vesicle breakdown (GVBD) and decreased thereafter. Plasma 20-S levels also increased with oocyte GVM in white bass, but were several-fold lower than DHP levels. Circulating E2 and T levels were greatest during GVM and GVBD in both species and decreased to low levels during oocyte hydration and ovulation. Follicles from white perch and white bass which received a priming injection of hCG in vivo, produced both DHP and 20-S in vitro after exposure to hCG and their oocytes underwent GVBD. Ovarian incubates from unprimed fish of either species produced only E2 and T and their oocytes did not complete GVBD. Oocytes from unprimed bass, but not perch, matured when follicles were exposed to hCG in vitro. Both trilostane and cycloheximide blocked in vitro production of DHP and 20-S and oocyte GVBD by white perch follices. DHP and 20-S were equipotent inducers of FOM in the GVBD bioassay. None of several other structurally-related steroids tested were effective within a physiological range of concentrations. These results indicate a role for DHP and 20-S in the control of FOM in white perch and white bass.  相似文献   

17.
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   

18.
Protein and amino acid composition of the mantle of juvenile O ctopus vulgaris (Cuvier, 1797) during fasting for 27 days were determined. Average protein content of octopus mantle was of 711.19 ± 46.80 g kg?1 DW, and it decreased with increasing fasting days. The non‐essential amino acids content was higher (486.18 ± 11.08 g kg?1 protein) than essential amino acids (425.82 ± 9.15 g kg?1 protein) at the start of the experiment (unstarved animals). The results suggest that the amino acid profile of the mantle where the most abundant amino acids are Arg, His, Lys, Gly, Leu and Pro could indicate a prolonged fasting condition (>20 days) or poor nutrition of O . vulgaris. This study supports the idea of using mantle for metabolic needs of starved O . vulgaris suggesting that the degradation pathway of amino acids to pyruvate and tricarboxylic acid cycle intermediates was favoured contrary to the degradation pathway of ketogenic amino acids. Special considerations should be taken concerning Thr, Ile, Ser, Ala, Asx (Asp, Asn), Glx (Glu, Gln) (because of their fast intake) and Lys and His (due to their stable contents) during a prolonged period of fasting.  相似文献   

19.
This study brings an integrated analysis about the relationship between water deterioration and its physiological consequences in live fish transport. The analysis was focused on the transport water and its deterioration, and physiological challenges imposed on the fish. Usual commercial handling procedures employed to mitigate fish stress during transport were discussed. Future topics of research for the establishment of safer fish transport protocols were proposed. Transport was classified into short (≤8 h) or long transport (>8 h). The main issue in short transports should be the prevention of water pH reduction, while in long transports it is the increase in ammonia. Plasma cortisol is the most employed marker for stress and is acutely elevated upon short episodes of transport, but remains elevated even in long‐transport events. Plasma glucose is perhaps a better marker for handling stress. Plasma lactate, pH, osmolality CO2 and ions should be more often evaluated. Plasma Na+ and Cl‐ are very useful markers of acidosis, due to their respective exchange for H+ and , for acid–base regulation. The establishment of species‐specific transport protocols should be preceded by such combined analyses of water and physiological parameters.  相似文献   

20.
Abalone populations have declined worldwide, generating interest in enhancement using hatchery‐reared individuals. In many cases, such restoration efforts have met with limited success due to high predator‐induced mortality rates. Furthermore, the mortality rates of outplanted hatchery abalone are often considerably higher than for wild individuals. This study uses northern abalone (Haliotis kamtschatkana) as a case study to determine whether hatchery‐reared abalone behave differently than their wild counterparts. In the field, outplanted hatchery‐reared abalone were significantly less responsive than wild abalone, in terms of number of abalone responding and intensity of response, to nearby movement and to physical contact with an inert probe. Also, when encountering a cue to which all abalone responded (a seastar predator), hatchery‐reared individuals remained subdued. Anti‐predator behavioural deficits in hatchery‐reared abalone were more pronounced in 4‐year‐old individuals than in 1‐year‐old individuals, suggesting an influence of either age or amount of time spent in the hatchery environment. These behavioural differences are expected to increase the vulnerability of hatchery‐reared abalone to predators, and are likely a major cause of their elevated predator‐induced mortality when outplanted.  相似文献   

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