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1.
Induction of ovarian maturation in Penaeus vannamei , by implantation of ganglion prepared from female lobster, Homarus americanus , with developing ovaries was investigated under tank culture conditions. Four of six females with thoracic ganglion implants were maturing while only two of thirteen females of the control groups with abdominal ganglion or no implant matured. Two ripe stage V were found 18 days after implantation of lobster's thoracic ganglion. This indicates that ovarian maturation of P. vannumei in tanks can be induced and accelerated by implantation of thoracic ganglion prepared from maturing females of another species. Ovarian maturation may be induced by a gonad-stimulating hormone, secreted by the thoracic ganglion of maturing females. This gonnd-stimdating hormone is not species specific in activity in the shrimp and lobster.  相似文献   

2.
Chinese catfish ( Clarias fuscus ) were successfully spawned in Hawaii using human chorionic gonadotropin (HCG) at dosage rates of two and four international units (IU) per gram body weight. Fish not injected with HCG did not produce viable eggs. Successful spawns with HCG occurred between May and October. Hatch rates of up to 80% were obtained during June, July, and August for those fish given either a 2 or 4 IU per gram body weight injection of HCG. Fish spawned in either May or October yielded significantly higher hatch rates when injected with 4 rather than 2 IU per gram body weight. Fish held at elevated temperatures (28 to 30 C) prior to the normal spawning season developed significantly larger oocyte diameters, 60 days earlier than fish held under ambient temperature conditions (21.5 to 24 C). Photoperiod manipulation at ambient temperature conditions was associated with earlier oocyte maturation, but photoperiod effects were much less important than temperature.  相似文献   

3.
将蜡样芽孢杆菌Y1和巨大芽孢杆菌BM1259混合培养,结合平板活菌计数、抑菌活性测定及体内拮抗试验,研究其对水产动物气单胞菌的抑菌效果。体外拮抗试验结果表明,这两种芽孢杆菌均能明显抑制嗜水气单胞菌NQ的增殖,抑制率分别为53.74%和56.12%。不同温度下的抑菌活性试验显示,2种芽孢杆菌的抑菌活性温度分别为32℃和29℃。体内拮抗试验结果表明,巨大芽孢杆菌能显著降低异育银鲫肠道气单胞菌的数量。提示巨大芽孢杆菌可作为潜在的水产专用微生态制剂。  相似文献   

4.
在中华绒螯蟹的育苗过程中,采用添加微生物的方法调节育苗水体的水质,结果表明:与对照池相比,试验池中的氨氮明显下降,溶氧量增加,pH值变化不大;河蟹各期幼体的成活率提高,从SouⅠ期幼体至大眼幼体,试验池的成活率为13.9%,对照池仅8.1%。因此,在河蟹的育苗生产上,利用添加有益微生物的水质循环装置,能有效地提高育苗产量,节约成本。  相似文献   

5.
孔雀石绿对日本鳗鲡的背景污染试验   总被引:1,自引:0,他引:1  
用高压液相色谱法检测孔雀石绿和隐性孔雀石绿,研究了水体使用孔雀石绿后,池塘底泥孔雀石绿残留和泥土背景污染导致的鳗鲡肌肉中孔雀石绿的残留和消除.连续使用三次孔雀石绿24 h后,水体中无孔雀石绿残留.池塘使用孔雀石绿溶液浸泡后,导致池底泥沙中孔雀石绿残留,部分采样点检测到隐性孔雀石绿于泥沙中残留.池底孔雀石绿的残留,将导致鳗鲡孔雀石绿在肌肉中的残留,隐性孔雀石绿将长期于肌肉中滞留.孔雀石绿背景污染的池塘,应改造至无背景污染后使用,才能保障鳗鲡无孔雀石绿残留.  相似文献   

6.
以烤鳗下脚料为原料,经蛋白酶水解后,提取水解动物蛋白,使废充物得到充分利用。通过正交实验,确定了木瓜蛋白酶、枯草杆菌蛋白酶、胃蛋白酶的最佳水解条件,选择了木瓜蛋白酶为最佳水解酶。  相似文献   

7.
渔用中药药剂防治黄鳝寄生虫病的研究   总被引:4,自引:0,他引:4  
以使君子、百部、贯众和榧子配制驱虫药。4味药中,使君子的功效最高,4味药以使君子4%、百部10%、贯众20%、榧子15%的比例配成的驱虫药效果最好,寄生虫检出率只有10%,比对照组降低了87.5%。  相似文献   

8.
A high percentage (98.3%, N = 60) of the marbled grouper Epinephelus microdon individuals captured from spawning aggregations during July and August 1993 in the waters surrounding the island of Koror, Republic of Palau, Micronesia, were in the stage of maturity at which final maturation and spawning could be hormonally induced. The sex ratio of the captured fish was highly skewed towards males (4 male:1 female). Sexually immature females comprised the smallest size class, (<0.6 kg body weight (BW) or 33.0 cm total length (TL)), while sexually mature females were restricted to the 0.6–1.5 kg BW (33.0–46.4 cm TL) groups. Males predominated in size classes >0.6 kg BW, and individuals >1.5 kg BW (46.4 cm TL) were exclusively male. All females with oocytes that averaged ( N = 50) >400 μm in diameter were successfully induced to spawn by a two-injection protocol using human chorionic gonadotropin (HCG) at total dosages of 2,100–3,200 IU/kg fish. All males used in the spawning trials were administered a single injection of HCG at dosages of 500 or 1,000 IU/kg fish. Fecundity ranged between 7.96 × 105−1.24 × 106kg BW, average spawned egg diameters ranged between 769–832 μm, percent fertilization ranged between 32.6%–99.9%, and hatching percentages were >90.0%. Total fat content of eggs obtained from a pooled spawning event was 14.1 mg/100 mg dry weight. The data indicate that HCG is a suitable treatment for the induction of spawning in marbled grouper females that possess a mean oocyte diameter of 400 μm or greater.  相似文献   

9.
二株鳗鲡益生菌对欧洲鳗鲡免疫应答的初步研究   总被引:1,自引:0,他引:1  
林煜 《福建水产》2006,(4):44-47
由养殖鳗鲡肠道分离、筛选出的益生菌A40209CDC4和A31009NA,添加鳗鲡饲料,细菌浓度达107cfu·g-1,连续投喂30d,测定试验鳗鲡白细胞吞噬活性、溶菌酶活力和血清抗体滴度.结果显示:与未添加细菌的对照组相比,添加益生菌试验组的白细胞吞噬百分比、吞噬指数、溶菌酶活力和血清抗体滴度无显著变化,说明筛选菌株作为饲料添加剂应用于欧洲鳗鲡未产生特异性刺激.  相似文献   

10.
美洲鳗白仔对三种饵料的选择性及消化率研究   总被引:3,自引:0,他引:3       下载免费PDF全文
报道了美洲鳗( Anguilla rostrata )白仔对水蚯蚓( Tubifex sp )、卤虫( Artem ia sp )和鱼卵三种饵料的选择性、消化率及摄食后的生长情况。试验结果表明,美洲鳗白仔对上述3 种饵料的选择性明显不同:水蚯蚓> 卤虫> 鱼卵。从其对3 种饵料的消化率及生长情况来看,水蚯蚓和卤虫对美洲鳗白仔的饲养效果较好,而鱼卵的饲养效果则较差。  相似文献   

11.
Growth, plasma steroids, and the appearance of gonads (histology and gonadosomatic index) were followed in South American catfish (surubim, Pseudoplatystoma sp.) raised in captivity in the aquaculture facility at The Ohio State University, Columbus, Ohio, USA, from 2003 until 2006. Broodstock growth showed a great individual variation and it did not seem sex dependent. The levels of 11‐ketotestosterone were high in males during the reproductive season. Three out of six females spawned after receiving two doses of carp pituitary extract (0.5 and 5 mg/kg) at 11‐h intervals. Fertilization was performed in only one female in February 2006. Egg size was 0.73 ± 0.06 mm in diameter at stripping. Two males released sperm, and it was used for fertilization. Sperm concentrations were 24 × 109 and 15.5 × 109 spermatozoa/mL in Male 1 and Male 2, respectively, and viability was confirmed after activation in 0.3% NaCl. Embryo survival at 9 h after fertilization was 44 and 23% for Male 1 and Male 2, respectively. Embryos hatched 15 h after fertilization. Larvae were 3.53 ± 0.09 mm in length at hatching and were successfully raised (72% survival after 2 wks) using live brine shrimp nauplii.  相似文献   

12.
13.
慢性氟中毒鸡精子质量测定研究   总被引:1,自引:0,他引:1  
蔡宗保 《畜禽业》2006,(12):28-29
为探明慢性氟中毒对鸡精子质量的影响,本研究采用饮水染氟方法,人工复制公鸡慢性氟中毒模型,在染氟第三十、五十和七十天分别进行人工采精,测定精子密度、精子活力和精子畸形率。结果表明,慢性氟中毒可导致鸡精子密度和精子活力降低明显,精子畸形率明显升高。对照组精子密度、精子活力和精子畸形率在不同试验时间没有明显差异。而试验组精子密度第五十天和第七十天明显低于第三十天,但第五十天与第七十天无统计学差异;精子活力第七十天也明显低于第三十天,但第三十天与第五十天、第五十天与第七十天之间无统计学差异;试验组精子畸形率不同测定时间都无统计学差异。说明鸡慢性氟中毒呈现一种特定的时间-效应关系,而且精子畸形率可以相对独立的表现鸡对氟的慢性毒性。  相似文献   

14.
上海黄浦江倪家浜口浮游生物调查与水质评价   总被引:3,自引:0,他引:3  
上海市黄浦江倪家浜口是中国2010年上海世博园后滩水系和东方体育中心人工湖的重要取水口,其水体状况直接影响世博园后滩湿地、世博园生活与日常杂用水,以及体育中心人工湖水体景观。为评估该地区水体健康状况,为后滩水系和人工湖取水工程建设与维护管理提供依据,我们根据2007年2月至12月倪家浜口不同潮位调查,分析了该区域浮游生物的种类组成、优势种类、物种多样性等特征参数的变化。调查期间共鉴定出浮游藻类8门45属,主要优势种为小席藻(Phormidium tenue)、四尾栅藻(Scenedesmus quadricauda)、极大螺旋藻(Spirulina maxima)等;浮游动物3门32种,主要优势种为萼花臂尾轮虫(Brachionus calyciflorus)、前节晶囊轮虫(Asplanchna priodonta)、发头裸腹溞(Moina irrasa)等。叶绿素a含量表现出明显的季节变化。多样性分析显示,浮游藻类香农威尔指数为0.88~2.96,浮游动物香农威尔指数为0.92~2.98。数据分析表明,种类数及多样性指数与温度呈正比,倪家浜口处于中度富营养化状态,水质处于中-重污带级,且夏秋季水质优于冬春季,当天高潮时水质优于低潮。  相似文献   

15.
In this short note information is presented about some preliminary laboratory experiments which indicate that full maturation of the ovaries in the prawn Penaeus orientalis can be induced by the removal of only one eyestalk.  相似文献   

16.
不同饲料对黄颡鱼消化酶活性的影响   总被引:5,自引:1,他引:5  
乔慧  黄成  王喆  潘建林 《淡水渔业》2007,37(1):58-61
将40尾成熟黄颡鱼(Pseudobagrus fulvidraco)分成两组,分别饲喂高蛋白的幼鳗人工配合饲料和低蛋白的鲤鱼人工配合饲料50 d,每10 d分别从各组中随机取3尾做消化酶测定。结果显示:幼鳗人工配合饲料组的黄颡鱼胃中淀粉酶比活力呈下降趋势,蛋白酶比活力呈上升趋势,肠中淀粉酶比活力变化不明显,而蛋白酶比活力呈上升趋势;鲤鱼人工配合饲料组的黄颡鱼胃内和肠内淀粉酶比活力均呈上升趋势,而蛋白酶比活力均呈下降趋势。淀粉酶比活力与蛋白酶比活力的比值(A/P值)比较显示:高淀粉成分的食物长期诱导下可以使黄颡鱼体内淀粉酶相对含量上升,并且出现食性转化的现象;高蛋白成分的食物长期诱导不能使淀粉酶相对含量一直下降。  相似文献   

17.
过氧化氢诱导紫彩血蛤排放精卵及其胚胎发育的研究   总被引:4,自引:0,他引:4  
采用浓度为0.1~10‰的H_2O_2海水处理紫彩血蛤,能诱导其排放精卵,排放率为60%~80%,其中H_2O_2浓度在0.5%~1‰之间时效果较好,排放率高达80%,并且诱导排放时间较短。文章还叙述了紫彩血蛤胚胎发育过程中性腺、精子、卵子以及胚胎发育各期的形态。  相似文献   

18.
Ovaries and testes from the Russian sturgeon at different stages of sexual maturity were incubated with ;sup3;H-androstenedione or 3H-pregnenolone. The major metabolites of androstenedione in both sexes were testosterone and 5- and 5ß-androstanediols, but no evidence was found for the gonadal production of 11-oxygenated androgens. Pregnenolone was converted to 17-hydroxyprogesterone, androstenedione and testosterone together with reduced metabolites. 11-Oxygenated androgens were found in female serum by gas chromatography-mass spectrometry (GC-MS), in serum of both sexes by radioimmunoassay (RIA), and was detectable by RIA in interrenal but not gonadal tissue. The results suggest that sturgeon may differ from teleosts in that 11-oxygenation may take place in extragonadal tissues.  相似文献   

19.
青蛤人工繁殖中常用的催产方法是阴干处理。若亲贝从异地购进,长途运输的过程也相当于阴干处理,具有催产刺激作用,入池后精.卵排放数量很大,但绝大部分是畸形卵,不能正常受精;即使是正常受精卵,到第3d就停止发育,本试验结果表明,异地采购的亲贝,经长途运输后暂养1d再催产.可以提高受精率。  相似文献   

20.
Ovulation and spermiation of pacu, Colossoma mitrei (Berg 1895), were induced with crude carp pituitary extract. Each female was injected with two doses containing, respectively, 0.5 and 5.0 mg of dried pituitaries per kg of body weight, with an 18-h interval between doses. Each male received a single dose of the same extract containing 0.5 mg of dried pituitary per kg of body weight. The ‘dry’ method of fertilization was used. Water temperature during the experiments ranged from 22 to 24.5°C. Ovulation occurred at 305 ± 13 degree-hours. The ratio, in percentage, of ova: body weight was 8.2 ± 3.5. The number of oocytes per gram of ova varied from 1249 to 1695 with an average of 1531 ± 136. Oocyte diameter increased significantly from 1097 ± 14 μm prior to the first dose, to 1252 ± 14 μm at stripping. The degree-hours to hatching varied between 559 and 575, with an average of 565 ± 7. Hatching percentage varied from 77 to 92.  相似文献   

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