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1.
Cai‐Xia Liu Xiao‐Ying Tan Shi‐Yuan Gong 《Journal of the World Aquaculture Society》2013,44(3):350-362
This study was conducted to determine the ontogenetic development of the digestive tract and its accessory structures (liver, pancreas, and gall bladder) in agastric larval Chinese sucker Myxocyprinus asiaticus with the histological and ultrastructural approaches from hatching to 56 days after hatching (DAH). On the basis of its feeding mode, and analyzing the main histological features of the digestive system, larval development in Chinese sucker was divided into three stages from hatching: stage 1 (endotrophic period): 1–6 DAH; stage 2 (endoexotrophic period): 7–14 DAH; stage 3 (exclusively exotrophic period): from 15 DAH onward. At hatching, the digestive tract of the larvae consisted of an undifferentiated straight tube. At 4 DAH, the mouth opened, and the digestive tract was differentiated into buccopharyngeal cavity, esophagus and intestine. At 7 DAH, fish started to feed exogenously. Yolk sac was completely exhausted at 15 DAH. Until 56 DAH, the digestive tract of the larvae displayed regularly arranged microvilli, abundant vacuoles, and protein inclusion bodies. The pancreas, liver, and gall bladder were functional from 6 DAH, which enabled larvae to ingest, digest, and assimilate the first exogenous food. In comparison with teleosts that have a stomach, the development of the digestive tract of the agastric Chinese sucker seemed relatively slow . 相似文献
2.
The Development of a Functional Digestive System in the African Catfish Clarias gariepinus (Burchell) 总被引：2，自引：0，他引：2
Johan A. J. Verreth Els Torreele Eljallil Spazier Ad Van der Sluiszen Jan H. W. M. Rombout Ronald Booms Helmut Segner 《Journal of the World Aquaculture Society》1992,23(4):286-298
The morphological and physiological development of the intestine, stomach, liver and pancreas of the African catfish, Clarius guriepinus (Burchell 1822), was investigated from hatching until 9 days after the start of exogenous feeding by histological, histochemical and immunohistochemical procedures. During the yolk sac period, lasting 48 hours at 30 C, the digestive system develops from a rather undifferentiated system into a distinct liver and pancreas and a segmented intestine (parts I to III). Insulin and glucagon producing cells were clearly found in the endocrine pancreatic islets from 14 hours after hatching onwards, while at the start of exogenous feeding, the exocrine pancreas showed an intense zymogen colouration. Exogenous feeding started three days after fertilization, i.e., 48 hours after hatching. At that moment, the rearing temperature was lowered to 27.5 C. The first day of feeding was referred to as day zero, changing into day 1 when the first 24 hours of feeding were completed. From the start of exogenous feeding onwards, aminopeptidase, non-specific esterase and ATP-ase were detected in the digestive system. Morphologically, the stomach was completed at day 4 of exogenous feeding. Gastric acid secretion started on day 4 and lead to a pH below 3.3 in the stomach on day 5. During the first four days of exogenous feeding, C-t-gastrin immunopositive cells were found throughout the gut, including the gastric epithelium. After day 4, the C-t-gastrin cells were only detected in the anterior intestine. The completeness of the stomach development was also marked by the appearance of non-specific esterase activity in the stomach epithelial cells on day 5. All data together clearly indicate that in Clarius gariepinus , the ontogeny of a functional digestive system has been completed on day 5 after the start of exogenous feeding, marking thereby the end of the larval period. 相似文献
3.
利用形态学和连续组织切片技术，对出膜后1-60d的斜带石斑鱼各期仔鱼、稚鱼和幼鱼的消化系统进行了光镜观察，描述了其消化器官发育过程和组织学特性。研究表明，实验水温为22.0-27.8℃时，孵化后第4天，上下颌形成，卵黄囊被吸收，消化系统明显分化成食道、胃、肠、直肠以及肝脏、胆囊和胰脏等，鱼体由内源性营养转向外源性摄食营养，表明其消化系统的形态变化与食性的变化相适应。此后随着鱼体的生长，其消化系统从功能和结构上逐步完善成熟。胰脏在出膜后第4天出现，是和肝脏相互分开的一个独立的器官，但是发育到第35-60天，位于肠道后部的胰脏组织内出现许多大空泡。 相似文献
4.
对丁Gui的胚胎发育进行了连续观察，并对其卵黄囊仔鱼在开口摄食之前的发育、生长以及不可逆点作了实验研究。结果表明：（1）丁Gui受精卵在水温21.5℃时，胚胎发育时间约为52h；（2）仔鱼在孵出后第7天开始摄食，初次摄食率第9天达100%，第12天降到50%，进入不可逆点；（3）仔鱼对卵黄囊的日净消耗量的最大值出现在出膜后第1天，体长最大增长率出现的在出膜后的第2天；（4）仔全出膜后第8天，卵黄囊全部吸收，同时，饥饿期仔鱼开始出现负生长。 相似文献
5.
California halibut Paralichthys californicus is an important commercial species with high aquaculture potential in Baja California Sur, México. To optimize the feeding
process using live prey and/or inert diets, we evaluated alkaline proteases, pepsin, trypsin, chymotrypsin, leucine aminopeptidase,
lipase, α-amylase, and acid and alkaline phosphatase activities on starved larvae and larvae fed live prey. Highest activities
were observed for alkaline protease, trypsin, chymotrypsin, leucine aminopeptidase, and alkaline phosphatase in feeding larvae
than starved larvae on day 4 after hatching. At day 5, a sizeable increase in all enzymatic activities was detected in feeding
larvae. Alkaline protease, trypsin, chymotrypsin, and alkaline phosphatase decreases progressively from day 5 until day 18.
At day 18, a slight pepsin activity was observed. This was considered an indicator of the start of digestive system maturation.
We concluded that total enzymatic equipment for this species is complete between day 18 and 30 after hatching. Based on this
evidence, early weaning from live prey to inert feed would be possible at this time. 相似文献
6.
为了解黄条鰤(Seriola aureovittata)早期发育阶段的消化生理特性,测定了黄条鰤胚胎、仔稚幼鱼阶段脂肪酶、淀粉酶、胰蛋白酶和碱性磷酸酶活性变化。结果显示,在黄条鰤仔鱼出膜前胚胎阶段,即能检测到脂肪酶、淀粉酶和碱性磷酸酶活性;初孵仔鱼体内(1 d)初次检测出胰蛋白酶的活性。脂肪酶和碱性磷酸酶比活力在仔鱼孵化后迅速增强(P<0.05),在4 d开口时,2种酶比活力达最高值;淀粉酶比活力在7 d时达最大值;胰蛋白酶比活力在仔鱼阶段缓慢上升,15 d时比活力最大。稚鱼阶段内脏团中脂肪酶、碱性磷酸酶和胰蛋白酶活性基本维持稳定,幼鱼阶段内脏团脂肪酶、碱性磷酸酶和胰蛋白酶活性都呈现上升趋势;稚鱼和幼鱼阶段内脏团中淀粉酶活性下降并基本稳定于较低水平。研究表明,黄条鰤仔稚幼鱼发育过程中,各种消化酶活性变化明显,且与其发育阶段和食性密切相关。在尚未摄食饵料的早期仔鱼体内已存在消化酶,认为其是母源传递而来,不是由外源性饵料所致;幼鱼阶段内脏团脂肪酶、碱性磷酸酶和胰蛋白酶比活力明显提高,这反映出随苗种生长发育,其肠道结构和消化机能逐渐完善,并且对脂肪、蛋白质的需求逐渐增强。 相似文献
7.
为了解黄条(Seriola aureovittata)早期发育阶段的消化生理特性,测定了黄条胚胎、仔稚幼鱼阶段脂肪酶、淀粉酶、胰蛋白酶和碱性磷酸酶活性变化。结果显示,在黄条仔鱼出膜前胚胎阶段,即能检测到脂肪酶、淀粉酶和碱性磷酸酶活性;初孵仔鱼体内(1 d)初次检测出胰蛋白酶的活性。脂肪酶和碱性磷酸酶比活力在仔鱼孵化后迅速增强(P<0.05),在4 d开口时,2种酶比活力达最高值;淀粉酶比活力在7 d时达最大值;胰蛋白酶比活力在仔鱼阶段缓慢上升,15 d时比活力最大。稚鱼阶段内脏团中脂肪酶、碱性磷酸酶和胰蛋白酶活性基本维持稳定,幼鱼阶段内脏团脂肪酶、碱性磷酸酶和胰蛋白酶活性都呈现上升趋势;稚鱼和幼鱼阶段内脏团中淀粉酶活性下降并基本稳定于较低水平。研究表明,黄条仔稚幼鱼发育过程中,各种消化酶活性变化明显,且与其发育阶段和食性密切相关。在尚未摄食饵料的早期仔鱼体内已存在消化酶,认为其是母源传递而来,不是由外源性饵料所致;幼鱼阶段内脏团脂肪酶、碱性磷酸酶和胰蛋白酶比活力明显提高,这反映出随苗种生长发育,其肠道结构和消化机能逐渐完善,并且对脂肪、蛋白质的需求逐渐增强。 相似文献
8.
Ontogenetic development of digestive tract and digestive enzymatic activities in Squaliobarbus curriculus larvae 
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下载免费PDF全文 Fanfan Shen Caijuan Li Teng Teng Yining Chen Jinqiang Guo Chuankun Zhu Qufei Ling 《Aquaculture Research》2018,49(9):3158-3166
Squaliobarbus curriculus is an economically important freshwater fish. The ontogenetic development of the digestive system of S. curriculus larvae was studied histologically and enzymatically from hatching to 30 days posthatching (DPH). Amylase, lipase, alkaline phosphatase and pepsin activities were detected from the hatching stage, indicating that these enzymes were genetically preprogrammed. Marked increases in intestinal amylase, trypsin and alkaline phosphatase activities between 10 and 20 DPH corresponded to feed acquisition and transformation. Larval development in S. curriculus could be divided into three phases: phase I (endotrophic period): 1–3 DPH; phase II (endo‐exotrophic period): 4–5 DPH; and phase III (exclusively exotrophic period): from 6 DPH onward. At hatching, the digestive tract of the larvae was an undifferentiated straight tube. On 3 DPH, the digestive tract differentiated into the mouth cavity, oesophagus and intestine. On 6 DPH, feeding was totally exotrophic and the yolk sac was completely exhausted. During the growth of S. curriculus larvae, the intestinal mucosa formed and the number of goblet cells and microvilli increased, demonstrating maturation of the digestive system. The study about the digestive development of S. curriculus larvae will contribute to better larval‐rearing strategies. 相似文献
9.
An understanding of the development of the digestive system of marine fish larvae is of critical importance in determining optimal feeding regimes for their culture. The present study provides information on the histomorphological development of the digestive system of clown fish, Amphiprion percula , larvae during the first month of life. Before hatching, clownfish larvae possess an alimentary tract, liver and pancreas with absorptive and digestive capabilities. The yolk sac is completely consumed within 5–7 days at 25 °C. Clownfish larvae readily accept rotifers after hatching and a complete dietary shift from rotifer to Artemia can be accomplished at 10 days after hatch (DAH). Gastric glands in the stomach first develop 11 DAH and proliferate by 15 DAH. Both non-staining vacuoles (NSV) and supranuclear inclusion vesicles (SIV) appear at 11 DAH in the midgut and hindgut respectively. Pinocytosis and extracellular digestion coexist for about 2 weeks after hatching. While SIV disappeared completely at 25 DAH, NSV continued to be a prominent feature of the midgut during the first month. 相似文献
10.
Growth and ontogeny of digestive function were studied in pikeperch (Sander lucioperca) larvae weaned on artificial food at different ages. Three weaning treatments initiated respectively on day 9 (W9), day 15
(W15) or day 21 (W21) post-hatching (p.h.) were compared with a control group, fed Artemia nauplii from first feeding until the end of the rearing trial on day 36 p.h. The digestive enzyme activities and the ontogeny
of digestive structures were investigated using enzymatic assays and histological methods. Growth of pikeperch larvae was
significantly affected by precocious weaning. Pancreatic (trypsin and amylase) and intestinal (leucine-alanine peptidase,
leucine aminopeptidase N and alkaline phosphatase) enzyme activities were detected from hatching onwards, increased at the
moment of first feeding and then decreased. Pepsin secretion occurred at day 29 p. h. only, concurrently with the stomach
development and differentiation of gastric glands. In the early weaning group (W9) the maturation process of intestinal enterocytes
seems to be impaired and/or delayed and several signs of malnutrition were recorded. Except for alkaline phosphatase activity,
no differences in enzyme activities and development of digestive structures were observed among the control, W21, and W15
groups. Moreover, at the end of the experiment, no differences in proteolytic activities were observed among larvae from the
different treatments, indicating that, in surviving individuals, the digestive structures were properly developed and the
larvae had acquired an adult mode of digestion. Based on the artificial diet used, our results suggested that pikeperch larvae
can be weaned from day 15 p.h. without significant adverse effect on digestive capacities (except for alkaline phosphatase)
or development of digestive tract, while earlier weaning impaired the onset of the maturation processes of the digestive system,
both in terms of morphological structures and enzymatic activities. 相似文献
11.
12.
R. Martínez-Lagos D. Tovar-Ramírez V. Gracia-López J. P. Lazo 《Fish physiology and biochemistry》2014,40(3):773-785
The leopard grouper is an endemic species of the Mexican Pacific with an important commercial fishery and good aquaculture potential. In order to assess the digestive capacity of this species during the larval period and aid in the formulation of adequate weaning diets, this study aimed to characterize the ontogeny of digestive enzymes during development of the digestive system. Digestive enzymes trypsin, chymotrypsin, acid protease, leucine–alanine peptidase, alkaline phosphatase, aminopeptidase N, lipase, amylase and maltase were quantified in larvae fed live prey and weaned onto a formulated microdiet at 31 days after hatching (DAH) and compared with fasting larvae. Enzyme activity for trypsin, lipase and amylase were detected before the opening of the mouth and the onset of exogenous feeding, indicating a precocious development of the digestive system that has been described in many fish species. The intracellular enzyme activity of leucine–alanine peptidase was high during the first days of development, with a tendency to decrease as larvae developed, reaching undetectable levels at the end of the experimental period. In contrast, activities of enzymes located in the intestinal brush border (i.e., aminopeptidase and alkaline phosphatase) were low at the start of exogenous feeding but progressively increased with larval development, indicating the gradual maturation of the digestive system. Based on our results, we conclude that leopard grouper larvae possess a functional digestive system at hatching and before the onset of exogenous feeding. The significant increase in the activity of trypsin, lipase, amylase and acid protease between 30 and 40 DAH suggests that larvae of this species can be successfully weaned onto microdiets during this period. 相似文献
13.
通过形态学与连续组织切片的方法,对美洲黑石斑鱼(Centropristis striata) 1-34 d仔鱼消化系统的胚后发育进行系统观察,分析描述鱼体消化道(食道、胃与肠道)以及消化腺(肝脏与胰腺)的发育过程.对1-15 d仔鱼连续取样,每次取样30尾,15 d后隔天取样,每次取样15尾.结果显示,在水温为(24±1)℃、盐度为30-32的条件下,初孵仔鱼卵黄囊体积很大,消化管为封闭的管状结构.美洲黑石斑鱼孵出3d后,口裂形成、开始摄食,肛门与外界连通,消化道逐渐分化形成食道、胃及肠道,肝脏、胆囊和胰腺也逐渐形成.7d后,卵黄囊与油球基本消失,食道、胃部以及肠道黏膜褶皱开始形成,消化道黏膜上皮细胞逐渐分化,肝脏出现脂肪颗粒,仔鱼具备了基本的摄食能力.11d时,仔鱼食道可见黏液细胞,随日龄的增加上皮组织中黏液细胞数量迅速增多,褶皱日益丰富;胃部分化形成贲门部、胃本体与幽门部,胃壁褶皱不断增多、伸长;肝脏血窦与中央静脉明显.20d时,鱼体胃腺形成,说明胃部消化、吸收蛋白质的能力增强;肠道次级黏膜褶皱出现,肠圈与褶皱更加复杂化;胰脏分布有大量酶原颗粒.32 d时,仔鱼消化道组织结构分明,自腔面向内依次为黏膜层、黏膜下层、肌层与浆膜层,消化道与消化腺结构和功能逐步完善.仔鱼3-7 d为内源性营养向外源性营养过渡期,应及时提供充足适口的生物饵料,仔鱼20 d后可以逐渐驯化投喂微型配合饲料. 相似文献
14.
Zhenhua Ma Huayang Guo Panlong Zheng Long Wang Shigui Jiang Jian G. Qin Dianchang Zhang 《Fish physiology and biochemistry》2014,40(4):1157-1167
Ontogenetic development of the digestive system in golden pompano (Trachinotus ovatus, Linnaeus 1758) larvae was histologically and enzymatically studied from hatch to 32 day post-hatch (DPH). The development of digestive system in golden pompano can be divided into three phases: phase I starting from hatching and ending at the onset of exogenous feeding; phase II starting from first feeding (3 DPH) and finishing at the formation of gastric glands; and phase III starting from the appearance of gastric glands on 15 DPH and continuing onward. The specific activities of trypsin, amylase, and lipase increased sharply from the onset of first feeding to 5–7 DPH, followed by irregular fluctuations. Toward the end of this study, the specific activities of trypsin and amylase showed a declining trend, while the lipase activity remained at similar levels as it was at 5 DPH. The specific activity of pepsin was first detected on 15 DPH and increased with fish age. The dynamics of digestive enzymes corresponded to the structural development of the digestive system. The enzyme activities tend to be stable after the formation of the gastric glands in fish stomach on 15 DPH. The composition of digestive enzymes in larval pompano indicates that fish are able to digest protein, lipid and carbohydrate at early developmental stages. Weaning of larval pompano is recommended from 15 DPH onward. Results of the present study lead to a better understanding of the ontogeny of golden pompano during the larval stage and provide a guide to feeding and weaning of this economically important fish in hatcheries. 相似文献
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16.
本文利用连续石蜡切片方法对军曹鱼消化系统胚后发育（1～29日龄）进行了光镜观察。结果表明食道前部内侧纵行肌纤维发达,后部球形粘液细胞更丰富;胃腺的分化较晚,在仔鱼后期(即出膜后8天)才见胃腺细胞团。胃幽门部无胃腺,但具发达的肌层。肠上皮的纹状缘出现较早,1日龄时就可见,而且发育较快,3日龄时很发达。 肠后段黏液细胞明显多于前段和中段。肝脏发育较早,但16日龄仔鱼才开始贮存脂质。胰腺为弥散型,2日龄出现。军曹鱼这些结构特点的变化是与其摄食、消化、吸收的功能相适应的,而且,军曹鱼的摄食方式以及食性也随着消化系统的发育而变化。 相似文献
17.
饥饿对白甲鱼(Onychostoma sima)仔鱼摄食、生长的影响 总被引：2，自引：0，他引：2
在实验室条件下,采用观察、测量记录外部形态特征等方法研究了饥饿胁迫下白甲鱼(Onychostoma sima)仔鱼的摄食、生长、形态和存活的变化。结果显示:在水温(20±1.5)℃时,饥饿组和投喂组白甲鱼仔鱼在孵化后第4天开始摄食,初次摄食率为48%,第6天初次摄食比率达到100%。饥饿组仔鱼抵达饥饿不可逆点(PNR)的时间为13.5 d,50%累计死亡率出现时间基本上与PNR出现时间相同(13.5 d),表明第13.5天为白甲鱼早期发育中较为敏感的阶段。试验期间,饥饿仔鱼体重、体长、眼间距和体高分别在第6、7、11和12天后均显著低于对照组(P<0.05)。试验结束(16 d)时饥饿组仔鱼体重、体长和眼径的瞬时增长率均显著低于摄食组(P<0.05),而头长、体高和眼间距差异不显著(P>0.05)。结果表明饥饿对仔鱼生长发育起延迟作用,混合营养期延迟投喂,仔鱼生长发育水平明显低于正常投喂仔鱼。 相似文献
18.
The present study provides information on the histomorphological development of digestive system of discus, Symphyosodon spp., larvae during the first month of life. Discus larvae are altricial at hatching, with an undifferentiated digestive
tract and a large yolksac, which is completely consumed within 7 days. The mouth opens 3 days after hatching (DAH) and the
larvae starts feeding on AF Artemia at 4 DAH when offered. At 3 DAH the digestive tract is differentiated with distinct esophagus, stomach anlage, and mid- and
hindguts. At 5 DAH, discus larvae is an active feeder, equipped with partly developed jaws and ossified gill arches and an
inflated swim bladder. The liver and pancreas are present and supranuclear inclusion vacuoles (SIV) appear in the hindgut
for the first time. Gastric glands in stomach were first observed 7 DAH and proliferated by 11–13 DAH. SIV were a common feature
in the midgut and hindgut epithelium until 15–23 DAH. Therefore, exclusive use of artificial diets should be postponed until
2–3 weeks after hatching. 相似文献
19.
运用组织学切片技术研究四指马鲅(Eleutheronema tetradactylum)出膜后1-30 d(Day after hatching,DAH)仔鱼的消化系统形态和结构的变化.结果显示,在温度29-32℃、盐度25-28、溶氧4.80-5.5 mg/L、pH 8.0-8.3条件下,1 DAH仔鱼消化管尚未分化,由紧贴腹壁和卵黄囊的肠管组成.卵黄囊在3 DAH时完全吸收完毕,仔鱼开口摄食,消化管也与外界相通,此后逐渐分化出食道、胃部和肠道,一定程度上能自主消化吸收食物维持自身生长,逐渐从内源性营养期过渡为外源性营养期.15 DAH时出现幽门盲囊和胃腺,消化道结构和功能成分进一步发育完善,消化能力显著提高,30 DAH仔鱼消化道具备与成体相似的结构和功能.肝脏和胰腺分别在2 DAH和5 DAH时分化,随着仔鱼的生长而快速发育,至30 DAH时具备与成体相似的结构和功能.四指马鲅消化系统的发育表现为结构与功能密切联系且逐渐发育成熟的特点.本研究根据四指马鲅消化系统的发育特点讨论了育苗过程中的三大危险期并提出应对措施. 相似文献
20.
Structural development of Pacific red snapper Lutjanus peru from hatching to the onset of first feeding 下载免费PDF全文
下载免费PDF全文 Iram Zavala‐Leal Silvie Dumas Edgar O. López‐Villegas Renato Peña Mauricio Contreras‐Olguín Laura Flores‐Montijo José De La Cruz‐Agüero 《Aquaculture Research》2015,46(5):1162-1174
Successful rearing of larval fish requires culture conditions and feeding strategies matching the ontogenetic status of larvae. This study describes the external morphology and development of organs and structures involved in the feeding process (i.e. sensorial organs, mouthparts and digestive system) from hatching until first feeding in Pacific red snapper. Hatching occurred 26 h after fertilization at 26°C and total length (TL) was 2.45 ± 0.08 mm. The larvae showed an undifferentiated eye and digestive tract. At 48 hah, TL was 3.31 ± 0.12 mm. Yolk and oil globule were still present. The mouth was still closed, but the Meckel's, quadrate, hyoid and hyomandibular cartilages were present. The retina was formed by 5 layers, and a thin layer of pigment epithelium was observed in the outer nuclear layer (ONL). At 70 hah, TL was 3.44 ± 0.22 mm. A remnant of oil globule was still present. The mouth and anus were open. At 93 hah, the number of cones in the ONL of the retina have increased and there was more pigment in the pigment epithelial layer. A joint between Meckel's and the quadrate cartilage and also a joint between the hyomandibular cartilage and the skull were present. The presence of live feed was detected in the digestive tract of these larvae. Based on these observations, the Pacific red snapper larvae is functional to start ingesting live feed between the 3rd and 4th day after hatching. 相似文献