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黄鳝流水无土饲养与静水有土饲养比较试验 总被引：1，自引：0，他引：1
对黄鳝流水无土饲养与静水有土饲养的生长速度、成活率等进行比较，在同等条件下，经两个月的饲养，流水无土饲养黄鳝平均体重１６．９４ｇ，静水有土饲养黄鳝平均体重１５．４２ｇ，前者比后者生长速度快７．１８％，成活率高４．３３％。 相似文献
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黄鳝微卫星引物筛选及其在保护遗传学上的应用 总被引：16，自引：1，他引：15
研究了远缘种鲤的微卫星引物对黄鳝的适用性。结果显示,31对鲤微卫星引物中有11对引物能对黄鳝DNA模饭扩增出特异性带谱。每对引物扩增的等位基因数在3～13个,平均每个位点有5．6个等位基因,显示了较高的多态性。其中引物P1最理想,其PCR扩增产物能区分来自湖南、广东和孟加拉3个不同地域的黄鳝种群。应用微卫星技术对3个不同地域的黄鳝基因组DNA多态性分析结果显示,湖南、广东和孟加拉黄鳝群体内平均相似率依次为95．5％,95.8％和93．5％,平均变异度依次为0．045,0．042,0．063。群体间的相似率及变异度分析显示：湖南黄鳝和广东黄鳝群体间平均相似率为91．0％,变异度为0．045;湖南黄鳝和孟加拉黄鳝群体间平均相似率和变异度分别为55．7％和0．443;广东黄鳝和孟加拉黄鳝群体间平均相似率和变异度分别为58．6％和0．414。综合微卫星分析结果、黄鳝的外形特征及地理位置,可以推测,广东黄鳝与湖南黄鳝为同一个生物种的不同地理种群,而孟加拉黄鳝为同属中另一个种。 相似文献
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对黄鳝流水无土饲养与静水有土饲养的生长速度，成活率等进行比较，在同等条件下，经两个月的饲养，流水无土饲养黄鳝平均体重１６．９４ｇ静水有土饲养黄鳝平均体重１５．４２ｇ，前者比后者生长速度快７．１８％，成活率最高４．３３％。 相似文献
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平均放养密度为３ｋｇ／ｍ２（尾重２１ｇ，全长３０ｃｍ），顺水泥池内以泥垅打洞作寄身巢的黄鳝，经９６ｄ的人工强化养殖，其生长比速为０．９６４４，生长指标为２８．９；平均增重率２７４．９％，平均每尾净增重５７．７ｇ，单产８．８ｋｇ／ｍ２。该结果初步表明，水泥池中强化养殖的黄鳝，生长速度远快于规格相近、在自然水域中生长的黄鳝． 相似文献
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７０只网箱共产黄鳝４２２５．６ｋｇ，平均每公斤５０元，产值２１１２８０元，去除黄鳝养殖成本７９３００元，养殖黄鳝获利１３１９８０元，投入产出比为１：２．７。其中，池塘中３８只网箱共产黄鳝２６４４．８ｋｇ，平均每箱７２ｋｇ，每平方米３ｋｇ，增肉倍数为１．４５；河沟３２只网箱共产黄鳝１５８０．８ｋｇ，平均每箱４９．４ｋｇ，１ｋｇ／ｍ＾２，增肉倍数为１．３。每只网箱的黄鳝平均产值为３０１８．２９元，平均 相似文献
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花鲈人工繁殖的研究 总被引：18，自引：0，他引：18
１９９３～１９９５年，作者从浙江沿海三门湾及象山港采捕花鲈亲鱼，经暂养促熟处理（控制水温、盐度、溶氧水平，投喂、填喂活饵，不定期注射适量的ＬＲＨ－Ａ等），雌鱼的性腺可发育到Ⅳ＿３期，对外源激素能引起正常的排卵反应。试验用的催产剂及剂量为：雌鱼每千克体重用１．５～２．５ｍｇＰＧ＋１２００～２２００ＩＵＨＣＧ＋７０～１４０μｇＬＲＨ－Ａ，或用６～１０ｍｇＤＯＭ＋２００～３８０μｇＬＲＨ－Ａ；雄鱼的注射剂量减半。在水温１４．５～１６℃的条件下，注射后的效应时间为３６～９７小时。本试验的平均受精率为８９．２２％，平均孵化率为７５．４３％。 相似文献
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研究了池塘集约化网箱养鳝水质调控和病害防治技术。试验池投放滤食性和刮食性鱼类，移植水草，周期性施用微生物制剂，适时加换水和调节水体ｐＨ值；放养鳝种前对池塘、网箱、鳝种进行消毒灭菌；驯食成功后及时内服药饵驱虫灭菌，定期外泼、内服药物预防，发现病症及时治疗等方法调节水质、防治病害。对照池水质调控和病害防治方法即一般养殖户做法，方法单一、无计划和规律，缺乏科学性。试验过程中定期测定水质和黄鳝生长指标，并做好养殖记录。结果表明，试验池主要水质分析指标均优于对照池，试验池黄鳝平均成活率比对照池高２１．４％，平均规格大３４．５ｇ／尾，平均产量高１．３３ｋｇ／ｍ２，平均效益高６３．８元／ｍ２。规模区试进一步验证了试验结果，说明试验设计的水质调控和病害防治方法科学、有效、可行。 相似文献
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１９９２年及１９９３年的５月，用ＨＣＧ、ＰＧ、Ａ型混合激素、高效催产合剂３号等激素对２８组鳜亲鱼进行了５批次人工催产。当水温为２０．５￣２６．５℃时，效应时间为１８￣３５小时。平均催产率８２．１％，获受精卵２９．７６万粒，孵出仔鱼１９．１５万尾，育成鳜夏花和乌仔１１９８５６尾。 相似文献
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六线鱼人工育苗技术研究 总被引：2，自引：0，他引：2
使用从海区采集和人工催产获得的六线鱼卵块１０９１ｇ，孵化仔鱼１１万尾，平均孵化率为５６％，仔鱼经４５～６０天培育，育成全长２．５～４．０ｃｍ，鱼种１．８３万尾，平均成活率２４．４％，专家验收认为，育苗量，苗种规格及生长速度均处国内领先水平，对卵块收集，人工孵化，苗种生长，饵料系列，育苗病害，饵料生物培育等问题进行了研讨。 相似文献
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Francisco Javier Sánchez Rosa Cal Juan José Otero María Jesús Lago Castora Gómez José Iglesias 《Aquaculture Research》2012,43(11):1729-1733
For the first time, a spontaneous spawning of hake was recorded in Spain in April 2009. The spawn was obtained from broodstock kept in captivity for two years at the facilities of the Spanish Institute of Oceanography in Vigo (NW Spain). Eggs were transparent, spherical and had an average diameter of 1.067 ± 0.024 mm; yolk occupied the majority of egg volume. The oil droplet had a diameter of 0.27 ± 0.03 mm. The incubation period of the eggs lasted for 4 days at 14°C and the duration from hatching to the total absorption of the yolk sac was between 5–7 days after hatching, at the same temperature. Newly hatched larvae had an average total length of 3.20 ± 0.13 mm and began feeding 6 days after hatching; a daily growth rate of 0.158 mm day‐1 was observed from hatching to yolk sac consumption. This paper describes the daily evolution of biometric and morphological characteristics of the different stages of embryos and larvae of European hake up to the age of 19 days. 相似文献
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Abstract – The persistent effects of embryonic temperature stress and individual parentage on fry swimming performance were examined in a cross‐fertilisation experiment using sockeye salmon (Oncorhynchus nerka). A fixed‐velocity test of burst swimming was used to assess the endurance capacity and behavioural performance of individual fry from 10 offspring families incubated at 12, 14 or 16 °C to hatch and then reared through yolk absorption and exogenous feeding stages in a common posthatch environment (average 6.9 °C). Fry burst swim time (BST) was influenced by an interaction between incubation temperature and family identity. Average BST was longer for fry from the 12 °C prehatch treatment compared to 14 and 16 °C, although differences were largely attributable to temperature effects on average fry size. Behavioural observations revealed that fish incubated at 16 °C performed more poorly, having a larger proportion of individuals that required stimulation to swim, fatigued more frequently or were classified as ‘nonswimmers’. Within all three incubation temperature treatments, mean BST varied significantly among offspring families, independent of fry mass and length. An interesting relationship was observed within the 16 °C treatment, whereby families with higher survivorship were characterised with lower mean BSTs. Collectively, these findings demonstrate that exposure to high temperatures in early sockeye salmon development can result in persistent, parentally mediated effects on fry performance. As such, these results provide important insight into how elevated temperature events during egg incubation may affect early life history selection processes and survival in stages beyond when the stressor is experienced. 相似文献
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盐度对棘头梅童鱼胚胎发育和仔鱼存活的影响 总被引：1，自引：0，他引：1
观察比较了11个盐度梯度[0、5、10、15、20、25、30(自然海水)、35、40、45、50]下,棘头梅童鱼(Collichthys lueidus)胚胎的沉浮情况、孵化时间、孵化率和畸形率,并测定了初孵仔鱼的不投饵存活系数(SAI)。结果表明:(1)棘头梅童鱼胚胎在海水盐度为30及以上时100%漂浮;盐度为25时,95%漂浮,5%悬浮;盐度为20时95%悬浮,5%沉底;盐度为15时95%沉底,5%悬浮;盐度为10及以下时100%沉底。在水温18～20℃的条件下,棘头梅童鱼胚胎在盐度5～40范围内经28～32 h能孵化出仔鱼,盐度对孵化时间影响不显著(P>0.05)。但孵化率和畸形率因盐度不同而有显著差异。综合分析表明棘头梅童鱼胚胎孵化的适宜盐度范围为15～35,孵化最适盐度范围在20～30之间。(2)在可孵出鱼苗盐度范围(5～40)内,棘头梅童鱼仔鱼SAI值为(1.80±0.03)～(11.85±0.02),与卵的孵化率呈正相关关系。仔鱼生存的适宜生长盐度为10～30,最适盐度范围为20～25。 相似文献
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本文研究了杂交鳢(Channa maculate♀×C.argus♂)的亲鱼斑鳢(C.maculata)培育、杂交鳢人工繁殖、孵化和鱼苗培育等技术。结果显示:斑鳢在杭州地区池塘条件下经人工培育可达性成熟,但无法在自然条件下过冬,需进行保温越冬。杂交鳢人工催产繁殖的适宜水温在22℃以上,以25～28℃为宜。25～30℃水温条件下,分二次注射LHRH-A2、HCG和DOM混合催产剂,其效应时间在32 h以内;采用自然受精,泡沫箱或网箱孵化,其平均催产率为93.3%,平均受精率为72.9%,孵化率为64.1%,孵化时间18～45 h;通过定时过筛、分级分养、适时驯食等技术培育20 d左右,鱼种全长可达3.3～3.8 cm,平均成活率56.5%。 相似文献
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进行了不同盐度对大银鱼受精卵孵化率的影响试验,结果表明,受精卵能够在２０以下盐度孵出仔鱼,但孵化率随盐度的升高而降低,孵出的仔鱼畸形随盐度的升高而升高,胚胎发育速度也相应减慢 。 相似文献
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2012—2015年,采用室内循环水养殖系统开展了长鳍吻鮈(Rhinogobio ventralis)亲鱼培育、人工催产和孵化技术研究。结果显示:3年间长鳍吻鮈均能在循环水养殖系统中培育成熟,2014年5月—2015年4月间培育存活率和成熟率最高,分别为85.3%~100%和77.3%~100%;对培育成熟的亲鱼进行了4种不同外源激素(PG、HCG、LRH-A2、LRH-A2+DOM)催产实验,结果为LRH-A26μg/kg+DOM 5 mg/kg合剂催产率最高,达88.3%;14、16、18、20和22℃5个温度组的受精卵孵化实验结果显示,孵化时间(H)与温度(T)呈显著负相关关系(H=0.573T2-30.393T+418.178,R2=0.982,P0.01),18℃和20℃组的孵化率分别为54.27%和56.07%,显著高于其他各组,表明长鳍吻受精卵适宜孵化温度范围为18~20℃。 相似文献
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R. Eckmann 《Fisheries Management and Ecology》2003,10(4):233-239
Alizarin red S from 200 to 5000 mg L?1 was used to mark the otoliths of whitefish embryos Coregonus lavaretus (L.) from 5 days after fertilization until shortly before hatching, to develop a method for evaluating the effect of stocking whitefish. Mark quality depended on developmental stage at the time of immersion. The best results were obtained when the otolith primordia had formed and had started aggregating to form the innermost part of the nucleus. This was verified by in vitro staining of otoliths where the primordia were more intensely stained than the remaining part of the nucleus. The volume ratio eggs to ARS solution, which was 1:10 in all but two treatments, must be observed when comparing fluorochrome concentrations, as mark quality decreased at higher ratios of 1:5 and 1:2. An average mortality rate of 35% in the most successful treatments was considered tolerable for a mass‐marking programme being used under commercial hatchery conditions. This method for marking otoliths of whitefish embryos with ARS during egg incubation is recommended for all cases where marking of larvae is not possible. 相似文献