首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 437 毫秒
1.
从白洋淀水产种质资源保护区捕获的抱卵虾中挑选出200 kg作为孵化用亲虾,经1020 d培育,受精卵破膜孵化出幼体。自然水温(2020 d培育,受精卵破膜孵化出幼体。自然水温(2030℃)条件下,青虾初孵幼体经2530℃)条件下,青虾初孵幼体经2530 d的培育,生长发育成体长1.030 d的培育,生长发育成体长1.01.5 cm的仔虾。2013年,利用450 m3水体共培育仔虾4 800万尾,培育密度最高达15.6万尾/m3,最低6.8万尾/m3,平均11.1万尾/m3。  相似文献   

2.
镨对青虾卵子孵化的影响   总被引:1,自引:0,他引:1  
研究了镨(Pr)对青虾(Macrobrachiumnipponense)卵子孵化出Sou状幼体的影响,结果表明:Pr^3 的最佳质量浓度为0.4-1.6mg/L,可孵化离12.4%-20.3%。青虾卵子对Pr^3的饱和吸收量为9.2μg/粒,饱和吸收率为36.8%。  相似文献   

3.
温度对青虾幼体变态发育及培育率的影响   总被引:4,自引:0,他引:4  
青虾的幼体培育正值我国高温(6~7月)时期,有关温度对青虾幼体的影响的研究尚未见报道。本文根据1997~1998年多种方式繁育青虾试验的数据,报道温度对青虾幼体变态发育及培育率影响的初步结果,旨在为青虾幼体培育提供有关参考资料。1材料与方法试验在湖北省监利县棋盘乡渔业管理区和洪湖市红旗湖渔场孵化队进行。在1997年5~7月及1998年5~7月里,试验青虾为自行繁殖培育的健康幼体。试验用水为螺山干渠与内荆河水,水质清新无污染,溶氧保持4mg/L以上。繁殖亲虾个体选择4±0.3cm,孵出■状幼体大小较…  相似文献   

4.
镧对青虾卵子孵化的影响研究初报   总被引:1,自引:0,他引:1  
本文研究了La^3+对青虾(Macrobrachium nipponense)卵子孵化出蚤状幼体的影响,结果表明:La^3+的最佳浓度范围为1.2~4.8mg/1,扣提高孵化率22.8%~27.7%,镧对青虾卵子孵化的促进作用是通过卵子对镧的吸收实现的。  相似文献   

5.
青虾是一种十分饕餐的生物,天性贪食而凶残,孵化出刚4、5天,即一进入溞状三期,就有共唼之恶癖,此期间,肉眼可观察到育苗池中有这样现象:部份幼体活泼好动,不断地出击其它幼体,进而一对对相抱,取一对  相似文献   

6.
目前,青虾养殖过程中多采用直接向养殖池塘中投放抱卵虾养成的方法,虽然操作简单、易于实施,但幼体成活率低、孵化不同步、密度无法控制,造成青虾规格参差不齐、总体偏小、商品率低。专池繁育青虾仔虾再按计划放养,越来越多地被养殖户接受。然而,由于青虾苗种培育产量低、放养量多、运输难度大等因素的制约,造成市场上大规格苗种供不应求。  相似文献   

7.
在青虾育苗中,饵料是影响幼体变态和成活的关键因素之一。2000年,我们在进行青虾育苗试验的同时,进行了青虾幼体饵料研究试验,现将试验情况报告如下。1 材料与方法  相似文献   

8.
本研究采用自制离体孵化装置,对日本米虾(Caridina japonica)不同发育期胚胎进行离体孵化研究,结果显示,水温为25.5℃时,日本米虾受精卵孵化大约需要25 d,发育积温为637.5℃。胚胎发育历经受精卵、卵裂期、囊胚期、原肠胚期、前无节幼体期、后无幼体期、前溞状幼体期和膜内溞状幼体期8个时期。各期离体胚胎均能孵化出幼体,膜内溞状幼体期离体胚胎孵化率最高,为(80.7±2.4)%,非离体孵化的对照组为(79.1±4.9)%,二者差异不显著;卵裂期离体胚胎孵化率最低,为(28.2±2.6)%,与对照组差异显著。各组离体胚胎所孵化出的Ⅰ期(ZⅠ)和Ⅱ期溞状幼体(ZⅡ)的变态率无显著差异。温度对日本米虾前溞状幼体期胚胎离体孵化影响显著,在15.0℃~32.5℃范围内,随水温升高孵化时间逐渐缩短,15.0℃时,前溞状幼体离体孵化时间为(436.8±124.8) h,32.5℃时缩短至(228.0±88.8) h,但温度高于29.0℃时,孵化出的幼体变态率开始下降。本研究可为日本米虾繁殖生物学及甲壳动物胚胎离体孵化技术研究提供参考。  相似文献   

9.
淡水青虾人工育苗及其工艺   总被引:8,自引:0,他引:8  
虞冰如 《水产科技情报》1992,19(1):17-20,22
本文报道了采用桶式和流水槽两种方式进行淡水青虾室内人工育苗试验的方法。试验共投放抱卵亲虾940尾,孵出幼体33万尾,培育出一日龄仔虾28万尾。幼体的成活率达85%,高于池塘内青虾自繁自淡育的成活率。试验表明:采用自然海水稀释和盐卤配制成的咸淡水培育青虾幼体均获得好的效果。此外,根据青虾育苗实践,提出淡水青虾育苗工艺条件和流程。  相似文献   

10.
为提高凡纳滨对虾受精卵孵化效率,改进优化了1种受精卵流水孵化装置,可有效地进行凡纳滨对虾无节幼体集约化高密度生产。流水孵化受精卵的孵化密度在1 000万~6 000万粒/m3,平均孵化率在85.0%~92.7%。流水孵化的孵化率与常规的产卵池孵化无显著差异,但孵化出的无节幼体的携菌量和损伤率、黏脏率明显低于产卵池孵化(P<0.05);同时,为筛选优质的无节幼体,采用光诱、流水清洗等方法处理无节幼体,结果表明,流水清洗可显著降低无节幼体的损伤率、黏脏率和细菌携带量(P<0.05),有效提高无节幼体的生物安全及育苗成活率。  相似文献   

11.
通过催产试验,在高活性促性腺激素类似物相互之间、在类似物与HCG之间、在类似物同HCG或HWHO复配而成的复配制剂相互之间、在类似物与其复配制剂之间,进行了催产效果的对比。结果表明,各种类似物对不同鱼类的催产效果各不相同;类似物的催产效果明显优于HCG;使用类似物复配制剂,其催产效果优于单独使用HCG或类似物。  相似文献   

12.
Reproductive performance of albino and pigmented channel catfish ( Ictalurus punctarus ) females was compared when spawning was induced with HCG (human chorionic gonadotropin) or Ovaprim 3 (domperidone and [d-Ala6, Pro9 NEt]-luteinizing hormone-releasing hormone). In 1985, only HCG was used to induce spawning. Albino females required more injections, had a longer latency period from time of first injection to spawning, and had lower spawning success (30%) than pigmented females (77%). No differences were observed between albino and pigmented females for time-of-day of spawning, number of eggs obtained by manual stripping, and number of eggs/kg body weight. In 1988, HCG, Ovaprim, and saline (control) were used to induce spawning. HCG induced spawning in 80% of albino and 71% of pigmented females. Ovaprim induced 67% of pigmented females to spawn, but only 2 of 5 albino females spawned. One of four pigmented females injected with saline spawned. Albino females yielded 40–50% fewer eggs/kg body weight than pigmented females. Other performance characteristics for albino and pigmented females were similar whether injected with HCG or Ovaprim. High temperatures encountered during the 1985 spawning season my have had a differential effect on albino and pigmented fish and may account for some differences in spawning success.  相似文献   

13.
尤颖哲 《福建水产》2016,(6):481-485
在人工育苗的过程中,对亲贝进行促熟培育获得高质量受精卵是开展规模化育苗的关键。波纹巴非蛤(Paphia undulata)亲贝存在性成熟同步率低、产卵不集中的问题,研究对波纹巴非蛤亲贝分别进行室内水泥池和室外土池人工暂养促熟培育,经5、10、15、20 d的暂养促熟培育后,采用阴干、流水刺激的方法诱导产卵,比较不同的暂养促熟方法和促熟培育时间对亲贝的性腺发育及催产效果的影响。结果表明:用室外土池人工促熟法,波纹巴非蛤亲贝性腺发育的成熟情况比室内水泥池促熟法好、死亡率低;且经室外土池人工促熟培育10 d,亲贝的性腺发育情况及催产效果最佳。  相似文献   

14.
Abstract Singhi, the Indian catfish Heteropneustes fossilis , attained gonadal maturity repeatedly in a single spawning cycle by photothermal treatment. After the first spawning, maintenance at 30 C and 14 h light/10 h dark for 3 wk induced recruitment of the next batch of mature oocytes for subsequent spawnings. The number of eggs released declined with each spawning. However, fertilizability of the eggs was maintained until the fifth spawning. Mature fish were induced to spawn by D-Lys6 salmon gonadotropin-releasing hormone agonist administration. The dose of salmon gonadotropin-releasing hormone agonist for the second and subsequent spawnings was determined to be 25-fold less compared to the dose administered for the first spawning. Fish released the maximum number of eggs upon induction when they were maintained continuously at 30 C and 14 h light/10 h dark for 6 wk. The result obtained in the present study points to a possibility of obtaining multiple spawnings from those species of farmed fish which spawn once a year.  相似文献   

15.
Forty-six white sturgeon females captured prior to their spawning migration in the San Francisco Bay and during their spawning run in the Sacramento River were induced to ovulate with three different hormonal substances: white sturgeon and common carp crude pituitary extracts, and [D-Ala6] GnRH analogue. All three inducing agents were potent at the respective doses of 2.5 mg, 4.0 mg and 0.1 mg dry matter per kilogram of female body weight. The best ovulatory responses and egg fertilities were observed in fish administered hormonal treatment during the months of March and April. Fish captured prior to and during their spawning migration exhibited similar spawning success.  相似文献   

16.
Serotonin induced spawning in six bivalve species using individual spawning techniques without any additional stimuli. Intragonadal injection of serotonin induced spawning in the bay scallop Argopecten irradians, the American oyster Crassostrea virginica, and the surf clam Spisula solidissima. Injection of serotonin into the anterior adductor muscle of the ocean quahog Arctica islandica, the ribbed mussel Geukensia demissa, and the hard clam Mercenaria mercenaria induced spawning. The dosage of 0.4 ml of 2 mM serotonin solution used in this study stimulated bivalves to spawn within 15 min.  相似文献   

17.
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   

18.
Hormone‐induced spawning of southern flounder Paralichthys lethostigma has produced substantial numbers of viable eggs, but wide variations in fertilization and hatch rates have been reported. Recently, sustained natural spawning of southern flounder broodstock, without hormone induction, has been achieved in our laboratory. Adults (average weight = 1.12 kg; N= 25), including 6 captured as juveniles in 1993 and 19 captured as adults during September 1998, were stocked in two 4.8‐m3 controlled‐environment tanks in October 1998 and held under natural photothermal conditions until January 1999, when an artificial winter photo‐period of 10 L:14 D was initiated and then maintained through April 1999. Sex ratio was approximately 13 females:8 males:7 unknown. Natural spawning was observed in early December 1998 and increased in frequency to a peak in March 1999, before declining in late April. Water temperature ranged from 13.9 to 24.5 C during the spawning period. Natural spawnings over 142 d produced a total of 18.3 × 106 eggs, with a mean fertilization rate of 28.0% (range = 0–100%), yielding 4.94 × 106 fertilized eggs. The mean percentage of eggs that remained buoyant in full‐strength seawater (34 ppt) was 41.3% (0–98%), while hatching rate of buoyant eggs was 37.3% (0–99%) and survival of yolksac larvae to the first‐feeding stage was 30.2% (0–100%). Gonadal biopsies in late April identified six females from both tanks as probable spawners. A preliminary comparison suggests that natural spawning produced much larger numbers of viable eggs per female, with higher egg quality (i.e., fertilization and hatching success) than hormone‐induced spawning. In contrast to natural spawning, hormone‐induced strip‐spawning enabled timing of spawnings to be more precisely controlled. These results suggest that a combination of both natural and hormone‐induced spawning of photothermally conditioned fish will help produce the large numbers of eggs required to support commercial production.  相似文献   

19.
Abstract. Oocyte maturation, ovulation and spawning were successfully achieved in the African catfish, Heterobranchus longifilis Valenciennes, using frog pituitary extract. During artificial spawning, oocyte maturation and ovulation were induced at a dosage of 7mg per kg of individual fish weight. Latency period varied from 7 h at 29°C to 11 h at 25°C. Dead eggs became opaque between 8 and 10h after fertilization while embryogenesis was found to be temperature dependent. Mean hatching and larval deformity rates were 63·08%± 7·56 and 8·08%± 1·93 respectively. During induced natural spawning, the extract was applied at a dosage of 35 mg per kg of female fish weight. Spawning occurred between 10 and 11 h after hypophysation. Mean hatching and larval deformity rates were 41·38%± 8·48 and 10·00%± 2·00 respectively.  相似文献   

20.
Reliable methods have been developed for controlled spawning of captive southern flounder, Paralichthys lethostigma, broodstock during their natural winter (December–February) spawning season. From 1999 to 2004, we evaluated the effects of manipulation of photoperiod and temperature on both advance and delay spawning to produce viable embryos throughout the year. Wild‐caught adult broodstock were held in 4.8‐ to 7.0‐m3 controlled‐environment tanks at a sex ratio of approximately 12 females to 4 males. Broodstock were subjected to different artificial photothermal conditioning regimes: extended winter (EW), accelerated (A‐10‐, A‐6‐, A‐4.5‐, and A‐3.8‐mo regimes), and delayed (D‐16‐ and D‐14‐mo regimes), with gradual and abrupt transitions, respectively, from long to short daylengths. Under an EW cycle, fish were exposed to constant short daylengths (10 L: 14 D) after the winter solstice in January. Eighty‐seven natural spawnings from December to April produced 18.3 × 106 eggs, with 20.9% hatching successfully (i.e., overall egg viability). Under an A‐10‐mo cycle, rate of decrease in daylength was accelerated after the summer solstice in July, to reach winter conditions in October. Seven induced spawning trials from October to November produced 897 × 103 eggs, with 40.4% viability. Under an A‐6‐mo cycle, rate of change of photoperiod was accelerated after the winter solstice in January, to reach winter conditions in July. Three induced spawning trials in July produced 550 × 103 eggs, with 14.7% viability. Under an A‐4.5‐mo cycle, broodstock exposed to EW from January through April were exposed to an accelerated cycle to reach winter conditions by October. Four induced spawning trials from September to November produced 729 × 103 eggs, with 28.7% viability. Under an A‐3.8‐mo cycle, broodstock exposed to EW conditions from January through April were exposed to an accelerated cycle to reach winter conditions by September. Five induced spawning trials from September to November produced 510 × 103 eggs, with 45.9% viability. Under a D‐16‐mo cycle, fish were exposed to a decelerated decline in photoperiod after the summer solstice in July, to reach winter conditions in May, when atretic females were observed. Under a D‐14‐mo cycle, fish were exposed to constant summer conditions from December through mid‐June and then to an abrupt decline in photoperiod to winter conditions in late June. Six induced spawning trials from September to November produced 763 × 103 eggs, with 13.0% viability. Production of viable embryos was greatest during the extended winter because of abundant natural spawnings. While successful natural spawnings were rare during the fall or summer, viable embryos were produced through induced spawnings during all seasons of the year, with no significant (P > 0.05) differences in egg viability. Extended winter conditions prolonged spawning from 3 to 5 mo. Accelerated (3.8–10 mo) regimes were effective in producing viable embryos from summer through fall, but a minimum of 5 mo was required to complete gonadal recrudescence. While constant long daylengths after the summer solstice delayed gonadal recrudescence, with spawning obtained 2.5 mo after an abrupt reduction to short daylengths, a decelerated decline in photoperiod did not. Artificial control of daylength enabled precise control of gonadal recrudescence and year‐round spawning in southern flounder without adverse effects on the quality of eggs and larvae and will improve availability of seedstock for commercial aquaculturists.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号