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1.
Oocyte maturation and ovulation in the Atlantic halibut, Hippoglossus hippoglossus (L.), examined using ultrasonography 总被引：1，自引：0，他引：1
High resolution ultrasound scanning was tested as a non-invasive technique for monitoring oocyte maturation and ovulalion in the Atlantic halibut Hippoglossus hippoglossus (L.). Female broodstock halibut were examined using a 7.5-Mhz linear ultrasound transducer, prior to and during spawning. Representative images of halibut ovaries are presented and discussed. Individual oocytes of spawning females were discernible during oocyte final maturation, due to the large increase in volume caused by water uptake. The yolky (vitellogenic) cocytes of pre-spawning fish were more reflective to ultrasound than hydrating oocytes. The resulting differences in depth of ultrasound penetration permitted easy distinction of pre-spawning from spawning females. In addition, short-term changes in the depth of ultrasound penetration were observed during repeated scanning of a spawning female, owing to progressive hydration of the oocyte batch destined for ovulation. Although of similar diameter, hydrating oocytes in the ovarian tissue could be discerned from eggs in the ovarian lumen because of the different acoustic properties of the surrounding media. The findings of the present study are considered promising for the future routine use of ultrasonography in halibut broodstock management. 相似文献
2.
克氏原螯虾大颚器对卵巢发育的影响 总被引：23，自引：2，他引：21
采用埋植和离体方法进行克氏原螯虾的大颚器（ＭＯ）对卵巢发育作用的研究,埋植大颚器７次能显著提高成熟系数和促进卵径增大,处于不同卵巢发育时期的克氏原螯虾大颚器提取物（ＭＯＥ）的离体研究发现,卵黄发生期的ＭＯＥ对初级和次级卵黄发生期卵径增大均有极显著的作用,而对卵黄发生前期的卵径增大无作用,处于卵巢发育早期的ＭＯＥ对卵黄发４生期卵巢小块总ＲＮＡ含量升高无显著作用,处于卵黄发生前期,卵黄发生期和恢复期卵 相似文献
3.
组织蛋白酶C是一种溶酶样半胱氨酸蛋白酶,近年我们报道了组织蛋白酶C的表达与日本囊对虾(Marsupenaeus japonicus) 卵母细胞最后成熟阶段密切相关,本研究对卵母细胞发育主要不同时相特别是卵母细胞最后生理成熟过程进行了连续观察,测定了组织蛋白酶C在卵母细胞发育过程中的比活性。结果表明,日本囊对虾卵母细胞发育可划分为9个时相,即卵原细胞时相、核仁时相、周边核仁时相、初级卵黄发生时相、次级卵黄发生时相、皮质棒早期时相、皮质棒中期时相、皮质棒晚期时相、排卵期时相,生发泡的破裂是在排卵之前就已经发生;免疫印迹实验结果显示组织蛋白酶C蛋白只在卵母细胞最后成熟阶段即皮质棒发生时期表达,但酶活性测定结果表明组织蛋白酶C比活力在即皮质棒发生前后没有变化,酶活性较低,以上数据提示组织蛋白酶C可能与受精时皮质棒的释放以及受精卵外胶膜的形成有关。 相似文献
4.
取不同发育阶段文蛤 (MeretrixmeretrixLinnaeus)活体解剖取出生殖腺 ,常规方法制成切片 ,以透射电镜(TEM )观察其卵母细胞的卵黄发生过程。结果表明 ,文蛤的卵母细胞卵黄发生期间 ,线粒体、内质网、高尔基复合体、溶酶体、微吞饮泡等细胞器均参与了卵黄粒的形成。卵黄合成早期的卵母细胞质膜伸出大量的微绒毛 ,并出现卵黄膜 ,胞质中有大量膜性小泡 ,溶酶体、线粒体、高尔基复合体和粗面内质网发达 ,卵黄前体物质逐渐增多。在卵黄合成中期 ,胞质内线粒体和内质网活动活跃 ,卵母细胞大量合成和积累卵黄物质 ,细胞质膜外凸 ,与外界进行物质交换。卵黄合成后期 ,卵质内贮存了大量的卵黄粒 ,细胞器不发达。此外 ,还对卵母细胞发育过程卵黄颗粒的细胞内、外原料来源进行了讨论 相似文献
5.
Michiya Matsuyama Shinji Adachi Yoshitaka Nagahama Katsuhiko Maruyama Shuhei Matsura 《Fish physiology and biochemistry》1990,8(4):329-338
Ovarian developmental stages and serum steroid hormone levels were examined at six different times of day (0100, 0600, 1000,
1300, 1600, 2000 h) in a marine teleost, the Japanese whiting Sillago japonica, which has an asynchronous-type ovary containing oocytes at various stages of development and spawns every day during a period
ranging up to three months. The largest oocytes in the ovaries at the active vitellogenic or post-vitellogenic stages were
found between 0100 and 1300 h. Oocyte maturation indicated by germinal vesicle breakdown (GVBD) occurred at 1600 h, and ovulated
oocytes were observed in the ovaries collected at 2000 h. These processes were accompanied by a significant daily change in
serum steroid hormone levels. The serum level of estradiol-17β showed a peak in fish with mature oocytes sampled at 1600 h.
In these fish, the second-largest oocytes in the ovaries were at the initial stage of vigorous vitellogenesis, the secondary
yolk stage. Therefore the highest level of serum estradiol-17β was considered to be due to the second-largest oocytes. Testosterone
levels remained low and constant throughout the experimental period. The serum levels of 17α,20β-dihydroxy-4-pregnen-3-one
(17α,20β-diOHprog) peaked at 1600 h at which time all fish had mature oocytes. These results indicate that the Japanese whiting
possesses a diurnal rhythm of oocyte development including vitellogenesis, oocyte maturation and ovulation, and further suggest
that daily cycles in oocyte growth and maturation which simultaneously take place in an ovary are regulated by diurnal secretions
of estradiol-17β and the maturation-inducing steroid, 17α,20β-diOHprog. 相似文献
6.
Abstract– The female reproductive traits of a small, North American catfish were studied over a two-year period in a population at the southern extreme of the species'range. The reproductive season was long for Noturus , possibly from February to September. Females matured at age 1 and probably reproduced in only a single year. Clutch sizes were 16–68 oocytes in females 33–47 mm SL, and only one lifetime clutch may be produced. Clutch size, dry mass and volume were related to female size, but ripening oocyte size was not. Clutch mass averaged 23% of total body mass just prior to spawning. Compared to a northern population, females had greater SL-adjusted body masses, clutch sizes and clutch volumes but smaller oocytes. Oocyte size accounted for 73% of the difference in clutch sizes and clutch volume 14%. Concerns about the comparability of present data for Noturus are expressed. The need to include many life-history traits, from several populations of each species, using standardized methods in analysis of functional responses is discussed. 相似文献
7.
通过对催产和未催产的长吻鮠脑垂体中腺垂体促性腺激素分泌细胞（ＧＴＨ 细胞） 的分泌活动分析,证实了用促黄体素释放激素类似物（ＬＲＨ－ Ａ） ５０μｇｋｇ 加ＤＯＭ５ｍｇｋｇ 混合注射催产长吻鮠,能有效地促使ＧＴＨ细胞分泌促性腺激素,诱导卵母细胞成熟和排卵,催产效果显著。超微结构的进一步观察,揭示了长吻鮠脑垂体ＧＴＨ 细胞中存在两种分泌颗粒,即分泌小球,直径１２００～２０００ｎｍ ,电子密度低;分泌颗粒直径３００ ～５００ｎｍ ,电子密度高。分泌小球释放与卵母细胞的发育成熟有关,分泌颗粒的释放则与排卵相关。 相似文献
8.
Matthew A. DiMaggio Jason S. Broach Cortney L. Ohs 《Journal of the World Aquaculture Society》2014,45(3):243-257
Pigfish, Orthopristis chrysoptera, readily undergo vitellogenesis in captivity, but final oocyte maturation (FOM), ovulation, and spawning can be unpredictable. The objectives of this investigation were to assess the effects of various doses of Ovaprim® (sGnRHa [salmon gonadotropin‐releasing hormone analog] + domperidone) and human chorionic gonadotropin (HCG) on FOM, ovulation, and spawning in pigfish. Ovaprim dosages investigated were 0.25, 0.50, 1.00, and 2.00 mL/kg, which were injected into the dorsal musculature of female pigfish. Male pigfish received one half the dosage administered to females to ensure spermiation. HCG doses of 500, 1000, 2000, and 4000 IU/kg were administered to female pigfish, with male pigfish once again receiving half the female dosage. Eggs were collected over a 72‐h period postinjection and enumerated and assessed for fertilization, hatching percentage, and survival to first feeding. Eggs and larvae were photographed and a suite of morphological parameters was determined. Hormone dose evaluations with pigfish showed that the low‐dose (0.25 and 0.50 mL/kg) Ovaprim treatments resulted in better spawning performance. However, superior egg and larval characteristics validate the 0.50 mL/kg dose as the preferred choice for use with pigfish. The four doses of HCG administered to pigfish performed unreliably in this study; thus, no dose recommendation could be made. 相似文献
9.
Murzina SA Meyer Ottesen CA Falk-Petersen S Hop H Nemova NN Poluektova OG 《Fish physiology and biochemistry》2012,38(5):1393-1407
Oocyte and liver histomorphology of the daubed shanny (Leptoclinus maculatus) from Isfjorden and Kongsfjorden in Svalbard were investigated during three Arctic seasons: summer (July), autumn (October) and winter (April). Three oocyte developmental phases were observed: primary growth phase, secondary growth phase and maturation phase. We observed four different developmental stages: (1) perinucleolus stage with cortical alveolus formation, (2) lipid droplets formation, (3) vitellogenesis stage and (4) maturation. Late maturation stage of oocytes in the ovaries was from the autumn season. Females accumulated lipids in liver (up to 35.2?% dw) and deposited large amounts of lipids into gonads (up to 52.2?% dw) during maturation. Lipid classes in female gonads changed seasonally, with relative increase in cholesterol during summer and depletion of storage lipids (triacylglycerols and wax esters/cholesterol esters) during the winter. Lipid composition in liver changed during oocyte development and spawning, as neutral lipids were transferred to developing oocytes during summer to autumn. During winter, storage lipids were depleted during starvation. Based on the increase in gonadosomatic index (GSI) with length and observed maturation stages, females seem to mature at a length of about 125-130?mm. The GSI and hepatosomatic index of large females sampled in autumn (September-October) were significantly higher than for females in late winter (April) and spring (May). These results indicate that spawning takes place during winter in Isfjorden and that energy reserves stored in the liver are utilized by females during gonadal development and reproduction. 相似文献
10.
11.
Mature northern pike were given various hormonal treatments in March or April in order to stimulate spermiation or to induce ovulation. In males the total amount of sperm collected after treatment increased, in comparison with saline-injected males, by 3–11 times with partially purified salmon gonadotropin (PPSG-activity: half of the highly purified s-GTH; injected at doses of between 5 and 100 μg/kg body weight); 3–6 times with crude carp pituitary extract (0.5–3 mg/kg body weight); and 3–7 times with fresh pike pituitaries (14 and 1.2 mg wet weight/kg body weight). The sperm obtained after hormonal treatment was of good quality. Intracardiac injection of superactive LRH analogue had no effect. In females, PPSG induced 90 and 100% ovulation at the doses of 50 and 25 μg/kg body weight. Dried salmon pituitaries (2.5 mg/kg, equivalent to 50 μg of PPSG) gave 25% ovulation; at 10 mg/kg, 25% complete ovulation was again recorded, but in addition 70% of the females showed oocyte maturation and partial ovulation. Similarly, dried carp pituitary (3 mg/kg) induced only oocyte maturation but no ovulation. The oocytes obtained after hormonal treatment were in general fertile. Intraperitoneal injection of LRH in an emulsified form induced neither oocyte maturation nor ovulation. The lack of effect of LRH analogue is discussed and shows that the use of this compound as a substitute for pituitary preparation is not very promising. 相似文献
12.
《Aquaculture (Amsterdam, Netherlands)》1987,66(1):43-52
Body length, oocyte diameter, germinal vesicle position, in vitro oocyte maturation response to progesterone, and plasma concentrations of progesterone, cortocosteroids, and 17α,20β-dihydroxy-4-pregnen-3-one (17α,20β-diOHP) were examined in white sturgeon females prior to their spawning induction and correlated with their subsequent ovulatory response. The relationship between broodfish size and ovulatory success was insignificant. Responsive females had larger oocytes and elevated plasma concentrations of corticosteroids and 17α,20β-diOHP, but did not differ significantly from nonresponsive females in progesterone concentrations. Germinal vesicle position and in vitro oocyte maturation response exhibited the closest relationships with ovulation, and can be used as practical predictors of ovulation for hormonally induced spawning of white sturgeon. 相似文献
13.
A series of sixteen environmental experiments, conducted under controlled laboratory conditions during the refractory period in the reproductive cycle of the grey mullet, determined the effect of photoperiod and temperature on the vitellogenesis of intraovarian oocytes. Fish subjected to the natural light cycle and ambient water temperatures (24–26°C) served as controls. A classification of stages of vitellogenesis (I–V) is used to determine the percentage composition of oocytes for each fish at intervals throughout the experiment following sampling in vivo.Onset of vitellogenesis is timed by the environmental conditions. A retarded photoperiod, irrespective of preconditioning photoperiod, plays a dominant role in stimulating oocyte growth. Temperature regulates vitellogenesis towards functional maturity. The combination of retarded photoperiod (6L/18D) and constant temperature of 21°C is the most effective for the completion of vitellogenesis of oocytes to functional maturity.Regular injections of pregnant mare's serum gonadotropin (PMSG) at 1 IU/g body weight are effective in initiating vitellogenesis. 相似文献
14.
ABSTRACT: The annual reproductive cycle, including the first maturity of ovarian development and plasma levels of testosterone (T) and estradiol-17β (E2), was examined in female Japanese catfish Silurus asotus reared under natural conditions. In addition, the possible period that final oocyte maturation and ovulation can be induced by human chorionic gonadotropin (hCG) injection were investigated. Results showed that female Japanese catfish matured 1 year after hatching under reared conditions. The beginning of vitellogenesis was in March and ovarian development and plasma T and E2 levels peaked in June. Thereafter, the gonadosomatic index gradually decreased to October and regression of oocytes at the tertiary yolk globule stage was observed. Female Japanese catfish could be induced to final oocyte maturation and ovulation by hCG treatment during the period from June to September. In addition, the fertilization rates were relatively high and stable during this period. These results suggest that yearling female Japanese catfish can be used as brood stock for seed production. This is the first study to investigate the annual reproductive cycle in Japanese catfish. These data will provide useful information regarding brood stock management and seed production. 相似文献
15.
太平洋牡蛎二倍体和三倍体卵母细胞发育的超微结构 总被引：1，自引：0，他引：1
本文利用电子显微镜比较研究了太平洋牡蛎二倍体和三倍体卵母细胞发育过程中细胞和各细胞器的超微结构变化。结果表明,在卵黄形成期,二倍体卵母细胞呈椭圆形,细胞器发达,细胞外布满微绒毛,卵黄粒多并均匀分布于细胞质中,卵母细胞生物合成旺盛,代谢活动强;而三倍体卵母细胞呈长条形或不规则形,细胞器少,不发达,细胞外未观察到微绒毛,卵黄粒少,有些细胞的卵黄粒畸形,卵母细胞生物合成及代谢弱。 相似文献
16.
We conducted a study to evaluate the effects of holding water temperature on the fecundity and egg quality of photo‐manipulated Atlantic cod broodstock. Adult cod Gadus morhua were distributed among several 25‐m3 tanks. Three separate photoperiods were used for each group to obtain three spawning per year (in May, July and December). While photoperiod was controlled, the temperature was not controlled and followed the ambient seasonal pattern. Due to the uncontrolled seasonal temperature used, each spawning group experienced different temperatures at a particular gonadal developmental stage. Otherwise, all groups were treated the same. Results showed that the May and July spawning groups released significantly more eggs per kg of fish (four and three times more respectively) than the December spawning group. The egg fertilization success and proportion of normal eggs were also higher in the May and July groups. Possible reason for the difference may be that the May and July groups experienced lower temperatures (4–7°C) during oocyte maturation and ovulation than the December group (7–9°C). Our results show the importance of using lower/natural temperatures during oocyte maturation and ovulation to obtain good quality eggs in photo‐manipulated cod broodstock. 相似文献
17.
B. Jalabert B. Breton E. Brzuska A. Fostier J. Wieniawski 《Aquaculture (Amsterdam, Netherlands)》1977,10(4):353-364
The efficiency of different hormonal treatments to induce ovulation of carp at low temperatures (13–15°C) was tested. “Priming” with a low dose (0.6 mg/kg) of carp pituitary extract was found necessary for a subsequent successful treatment with 17α-hydroxy-20β-dihydroprogesterone (17α-20β P) (2 mg/kg) 1 day later. The eggs produced by this method showed satisfactory fertilization (75–96%) and hatching success (70%).On the other hand, normal hypophysation (5.4 mg/kg) following priming resulted only in partial ovulation and oocyte resorption at this temperature.Priming was shown to increase the gonadotropin level in plasma from about 2 to 35 ng/ml and to induce germinal vesicle migration toward the periphery of oocytes. Neither 17α-20β P nor desoxycorticosterone alone or in association gave any positive result in the absence of a preliminary priming. 相似文献
18.
Anita M. Kelly 《Journal of the World Aquaculture Society》2013,44(1):115-123
This study monitors the progression of oocyte size and plasma hormone profiles of female channel catfish, Ictalurus punctatus, at monthly intervals to stage expectant ovulating, females for strip spawning. The “critical minimum” diameter of an oocyte to reach threshold maturity for channel catfish was 2.5 ± 0.21 mm. Monthly increases of oocyte diameters and plasma vitellogenin concentrations were linear until spawning. The reproductive performance of cannulated and noncannulated catfish did not differ, negating adverse effects of routine cannulation. This study suggests oocyte diameter in channel catfish can be used as a predictive factor to determine and stage potential broodfish suitable for hormone‐induced spawning. 相似文献
19.
M. Piccinno R. Zupa A. Corriero G. Centoducati L. Passantino A. Rizzo R. L. Sciorsci 《Fish physiology and biochemistry》2014,40(4):1191-1199
Contractions of ovarian tunica albuginea, the teleostean cystovary wall layer containing smooth muscle fibres, facilitate oocytes and fluids movements within the ovary, oocytes ovulation and spawning. Fish isotocin, the homologue hormone of mammalian oxytocin, plays a significant role in ovulation, oviduct contraction and spawning. In the present study, ovarian wall spontaneous contraction, as well as isotocin in vitro effect on tunica albuginea contractility, was analysed in female seabream in different reproductive conditions: vitellogenesis, regressing (post-spawning) and extensive atresia. Tunica albuginea spontaneous contractility was recorded using ovary wall strips mounted in an organ bath containing modified Ringer’s solution. The strips were then exposed to cumulative doses of isotocin (6, 30, 60 μg/ml). Female seabream in regressing condition exhibited the highest level of tunica albuginea spontaneous contraction amplitude compared with the other two groups. Only fish in vitellogenesis state showed a significant increase in contraction amplitude after isotocin administration at the dose of 30 μg/ml. The same group exhibited also a significant isotocin dose-dependent decrease in the contractile frequency. These results confirm the involvement of isotocin in stimulating tunica albuginea contractile activity during the oestrogen-regulated phase of vitellogenesis, whereas the absence of significant effects of isotocin on ovarian contractility in fish at the regressing state might be ascribed to the occurrence of a contractile activity autonomously regulated by the internal pacemaker system. The absence of exposed isotocin receptors could explain the lack of effects of the isotocin administration in seabream showed extensive atresia of the follicular cells. 相似文献
20.
The aim of this study was to induce and synchronize spawning of pejerrey Odontesthes bonariensis (Valenciennes, 1835), using gonadotropin releasing hormone agonist (GnRHa) implants. In the first experiment, the ovarian condition was assessed by ovarian biopsies and the measurement of the genital pore width (GPW). Females having the leading clutch of oocytes with a diameter of around 800–900 μm and a GPW between 4.5 and 5.5 mm were treated with GnRHa implants. Eighty per cent of females spawned between 2 and 9 days after treatment, 12 days earlier than 20% of the fish in the control group that presented signs of spawning activity. In order to avoid any possible ovarian injury and/or stress by the catheterization procedure, in a second experiment, females were selected only by visual inspection of the abdomen and GPW measurement. As in experiment 1, 80% of females spawned between 2 and 8 days after treatment, 8 days earlier than 30% of the fish that spawned in the control group. In both experiments, fertilization and hatching success were similar between control and GnRHa‐treated groups. These results clearly demonstrated that GnRHa implantation can advance and synchronize ovulation and spawning in pejerrey without affecting egg quality. 相似文献