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乌鳢繁殖设施一般采用露天土池、池塘中设置网箱、大棚温室、水泥池、家鱼孵化环道等类型,关于专用繁殖设施的研究报道较少。近几年来,山东省微山湖地区于每年的4～6月份,采用专用孵化设施开展乌鳢繁殖,取得了较好的效果。本文对该设施的建设、运行及繁殖效果进行了总结,为今后进一步提高该设施的繁殖效果提供参考。 相似文献
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正采用大鳞副泥鳅规模化繁殖设施开展繁殖,比自然繁殖更好控制,产卵率、受精率、孵化率更高,通过对500组大鳞副泥鳅进行了繁殖试验,结果为产卵率93%,受精率85%,鱼苗培育成活率51%。同时,该设施还有很大的改进、提高空间。 相似文献
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ABSTRACT: The dolphin fish, Corphaena hippurus Linnaeus, is one of the most important migratory fishes on the east coast of Taiwan. Present results are based on an investigation of 1439 specimens caught using long-line and driftnet, and set net collected monthly between September 1996 and September 1997. The sex ratio of female to male and female combined was 65%, demonstrating a female predominance. Oocytes became mature and transparent when they attained 1.0 mm in diameter. The total number of oocytes per ovary was estimated to range from 2.78 × 105 to 23.48 × 10>5 , but batch fecundity was noticeably lower than the total number of ovarian eggs, ranging 5.3–32.7% (average 30.1%), and the relative fecundity ranging 10–344/g bodyweight (mean 111/g bodyweight). Minimum body size at sexual maturity was estimated to be 51 cm for both sexes. Dolphin fish spawned throughout the year with reproductive activity peaking in February to March. It is suggested that the dolphin fish has an extended spawning season, during which it lays eggs almost continuously. 相似文献
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J. K. Sundaray K. Ohta A. Yamaguchi T. Kitano M. Matsuyama 《Fish physiology and biochemistry》2005,31(2-3):137-141
Pseudolabrus sieboldi, wrasse being a diurnal spawner provides a good opportunity to study the endocrine mechanism of estrogen formation in brain
and gonads. Moreover, an extremely large amount of E2 was produced in serum and testis of wrasse. It is assumed that the presence
of E2 may play a major role in diurnal gametogenesis in male fish. In this study brain type aromatase have been isolated,
cloned and sequenced from the brain of wrasse. Further, the expression pattern of brain type aromatase in gonads and adult
tissue of male and female fish have been analyzed. In addition, the diurnal expression pattern of brain type aromatase in
both male and female fish brain during spawning season have been analyzed.
The P450arom (br) was isolated, cloned and sequenced from both male and female bamboleaf wrasse. The P450arom (br) gene (1877
sequenced nucleotide) contains an ORF of 1470 bp, a 5′-UTR of 18 bp and at least 407 bp in 3′-UTR. The amino acid sequence
homology in the coding region of wrasse P450arom (br) is high compared to that of medaka, Oryzias latipes (80%), rainbow trout type 2, Oncorhynchu mykiss (78.2%), fugu, Takifugu ribripes (78%) rainbow trout type 1, (76%), goldfish, Carassius auratus (66.8%) and zebrafish, Danio rerio (66.2%). Expression study reveals that P450arom (br) mRNA were most abundant in brains of both male and female fish throughout
the day during the spawning season. RT-PCR study revealed that P450arom (br) was expressed in skin, anal fin and tail fin
of both male and female wrasse. P450arom (br) was not detected at any time of the spawning day in either ovary or testis of
wrasse. 相似文献
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本文研究了淤泥湖产太湖新银鱼(Neosalanx taihuensis)春夏季繁殖时期生殖群体的体长、性比、生殖力、卵的特性、产卵场、产卵期等繁殖生物学。并记述了太湖新银鱼的繁殖生态条件等资料。 相似文献
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控制水域电压为75 V,电流280 m A,持续电刺激5 500 ms左右,电刺激的作用强度是使鱼既能达到休克昏迷状态又能在几分钟内苏醒。通过对1月龄的稀有鮈鲫(Gobiocypris rarus)进行电刺激,观察电刺激对其性腺发育及性成熟后繁殖的影响,以期为渔政部门评价电捕鱼行为对鱼类资源的影响提供参考。结果表明,电刺激1次组、电刺激3次组和电刺激5次组可以促进雌雄鱼的生长和性腺发育,连续电刺激组对雄鱼的生长和性腺发育影响不大却会抑制雌鱼的生长和性腺发育;电刺激1次组、电刺激3次组和电刺激5次组对性成熟后雌雄鱼的繁殖没有产生显著差异,而连续电刺激组对性成熟后雄鱼的繁殖没有产生显著差异,却会造成雌鱼不产卵、或产出的卵颜色泛白,且可产卵雌鱼的产卵周期平均延长4.5 d,产卵量平均减少36粒,受精率平均降低9.2%。组织切片观察发现,电刺激1次组、电刺激3次组和电刺激5次组对性成熟后雌鱼的卵巢没有造成影响,而连续的周期性电刺激对性成熟后雌鱼卵巢中大的卵细胞的细胞膜造成了损坏,细胞膜界限变得不清晰;电刺激对性成熟后雄鱼精巢没有造成影响。 相似文献
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Jose M. Ridelman Ronald W. Hardy Ernest L. Brannon 《Aquaculture (Amsterdam, Netherlands)》1984,37(2):133-140
Adult female rainbow trout (Salmo gairdneri) were fed a commercial trout production diet until approximately 40 days prior to spawning at which time the fish were divided in two groups. One group continued to be fed while the other group was starved until spawning. Egg size, egg number, ovary weight, and egg proximate composition were examined periodically starting 5 months before spawning. Muscle tissues of the fish were sampled at spawning to measure somatic depletion of proximate consituents in the two groups. Egg hatchability was determined by incubating test lots from each spawning female. No significant differences (P > 0.05) were found in egg hatchability between the fed and starved groups. Changes in proximate composition were observed in the eggs during the months prior to spawning, but no differences were detected between the eggs of the starved and the fed groups. Short-term starvation did not significantly alter the proximate composition of muscle tissue of the spawned female trout. 相似文献
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本文研究了福建省东山岛西埔湾港养斑鰶性腺周期发育、成熟系数周年变化、个体生殖力以及雌雄同体。港养斑鰶能在半封闭式湾内发育成熟而且自然产卵。其卵细胞发育分为6个时相,精巢发育分为6期。卵膜由透明带、外放射带和内放射带组成,内有孔道结构。第4时相中期卵母细胞的内放射带有7～8层纤维状片层。产卵后鞘膜细胞和颗粒细胞分裂增殖变成游走的吞噬细胞。西埔湾港养斑鰶Ⅰ龄鱼初次性成熟,生殖季节从12月下旬至翌年3月下旬,生殖盛期为2月,雌鱼成熟系数高达17.88％。个体绝对生殖力为7575～72621粒,平均 35310粒,系属于分批产卵类型,第1批生殖力大于第2批。 相似文献
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This study documents early out-of-season induced spawning of channel catfish Ictalurus punctatus. During the early spring (February–April) of 1999, 2000 and 2001, ponds containing (1) male and female channel catfish (mixed-sex ponds) or (2) male channel and blue catfish I. furcatus only, or female channel catfish only (single-sex ponds) were heated to 24–30°C to encourage gonadal maturation and spawning. Unheated ponds were stocked with males and females and were monitored during the duration of heating. When natural spawning occurred in the heated ponds, the fish were captured by seining and unspawned females were injected with 100 μg kg−1 of synthetic leutenizing hormone-releasing hormone. Injected females were either paired with males or held in communal all-female groups, and monitored for ovulation. Eggs were collected and fertilized with sperm of channel catfish or blue catfish. Females paired with males were induced to spawn 44 days (mixed-sex ponds) and 50 days (single-sex ponds) before natural spawning occurred in unheated ponds. Spawning latency (the time between injection and ovulation) and the percentage of neurulated embryos from eggs fertilized using channel catfish sperm was not different between spawning before the natural season (P=0.68) and during the natural season in fish from mixed-sex ponds (P=0.57). Females held in all-female groups produced eggs 34 days before the onset of spawning in unheated ponds. Spawning latency was not different between spawns before and during the natural season (P=0.16), and the percentages of neurulated embryos from eggs fertilized with channel catfish sperm (P=0.76) or blue catfish sperm (P=0.77) before or during the natural season were not different. This study demonstrates the feasibility of conditioning of channel catfish females for early out-of-season induced spawning in the laboratory. 相似文献
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Reproductive ecology of two cyprinid fishes in an oligotrophic lake near the southern limits of their distribution range 总被引：3，自引：0，他引：3
A. S. Tarkan 《Ecology of Freshwater Fish》2006,15(2):131-138
Abstract – The reproductive activities of two dominant fish species, roach Rutilus rutilus and rudd Scardinius erythrophthalmus were investigated from August 2000 to July 2002 in an oligotrophic lake, Lake Sapanca, in the northwest of Turkey. A total of 907 roach and 593 rudd individuals were examined. Macroscopic appearance of ovary, gonadosomatic index and oocyte diameter frequency distribution suggested that the spawning season of roach and rudd were from early April (13 °C) to late May (18 °C) and from early May (17.5 °C) to late June (23.5 °C), respectively. The spawning cycles of both species showed the same tendency in two successive years. The estimated mean total lengths at first maturity ( L T50 ) were 12.26 and 14.98 cm for male and female roach, respectively, and 7.12 and 8.10 cm for male and female rudd, respectively. The sizes at 50% maturity corresponded to 3 years for roach and 1 year for rudd, for both sexes. The ratio of males to females was 1.3:1 and 1.2:1 for roach and rudd, respectively. The average condition factor K was 1.21 for rudd and 1.14 for roach, and it was not affected by sex or reproductive effort. Absolute fecundity varied from 7829 to 95,387 eggs between ages 3 and 9 for roach and from 1807 to 35,629 eggs between ages 1 and 7 for rudd. Comparisons of these results with earlier studies from more northern regions revealed that spawning of both species in this area started earlier, but spawning temperature and the duration of spawning was approximately the same. 相似文献
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Skipped spawning in female iteroparous fishes 总被引：10，自引：0，他引：10
It is often assumed that iteroparous fishes spawn annually once reaching sexual maturity, but this is not always the case. This paper reviews available information on skipped spawning in female teleost fishes. All instances of non‐annual spawning are described as one of three types (retaining, reabsorbing, resting), depending on where in the normal spawning cycle development has been interrupted. Retaining ripe eggs is caused by conditions experienced during the spawning season (fish density, mate availability, pollution), whereas failure to start vitellogenesis (resting) or the breakdown of all oocytes that enter into vitellogenesis (reabsorbing) is caused by factors experienced prior to the spawning season (primarily temperature and poor nutrition). It is speculated that the relative shortage of data on non‐annual spawning may be because of difficulties in identifying non‐reproductive individuals. In an attempt to rectify this situation, the criteria needed to identify females undergoing the three forms of spawning omission are presented in terms of external appearance of gonads, gonad indices, and histological analysis. The energy saved by not spawning in a poor year may lead to increased survival and the probability of spawning in subsequent years. As the cumulative number of progeny gained by surviving to spawn in multiple subsequent years outweighs the number of progeny lost by not spawning in a given single year, occasional omission of spawning may constitute an adaptive trait in long‐lived iteroparous fishes. 相似文献
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珠江水系唇鲮的生物学研究 总被引：2，自引：0，他引：2
唇鲮(SemilabeonotabilisPeters)是珠江水系重要的经济鱼类之一。本文从唇鲮的形态特征、年轮特征、体长与体重的关系、繁殖习性以及食性等方面进行了研究。结果表明:唇鲮的年轮分为疏密型和切割型2种,新年轮形成期主要是在2~4月份;体长(L)与鳞长(R)之间的关系可用R=0.1998L-0.7624表示,体长(L)与体重(W)之间的关系可用W=0.0236L2.9538表示;自然界中以3龄鱼为主;产卵季节为2~5月份,属一次性产卵类型,相对怀卵量2350粒/g,绝对怀卵量为17575粒/ind;雌雄比例为1.91∶1。唇鲮以摄食硅藻为主,对硅藻有较高的消化率,可达86.3%。 相似文献