人工养成史氏鲟亲本的杂交试验

用人工养成史氏鲟雄鱼的精液给野生史氏鲟及野生中华鲟雌鱼的成熟卵子授精，结果证明，人工养成史氏鲟的精子，其活力不低于野生史氏鲟，前者的受精率为79.3%，孵化率84.2%；后者的受精率为73.8%，孵化率81.7%。与中华鲟原种的后代相比，人工养成史氏鲟（♂）与野生中华鲟（♀）的杂交后代具有生长速度快、存活率高，抗病力强和耐运输等优点；与史氏鲟原种的后代相比，杂交鲟的适温范围明显大于史氏鲟，它具有中华鲟适应高温的能力。中华鲟与史氏鲟的杂交种有可能成为我国鲟鱼养殖中的优良品种。     

中华鲟全人工繁殖历史之最 获受精卵21万粒

长江三峡集团中华鲟研究所,在一组子一代中华鲟亲鱼全人工繁殖条件下,成功产下受精卵21万粒,产卵规模已达到野生中华鲟自然繁殖的水平,标志着中华鲟全人工繁殖技术体系基本成熟。20世纪80年代,科研人员利用野生中华鲟亲鱼人工繁殖培育出子一代。2009年以来,中华鲟研究所连续4次成功实施中华鲟全人工繁殖,前3次繁殖获得受精卵数量分别为4万枚、5万枚和10万枚。产卵规模已经达到野生中华鲟自然繁殖的水平。子一代成功繁育出子二代中华鲟,这也是世界     

中华鲟MHC IIB基因遗传多样性初步研究

为了给中华鲟(Acipenser sinensis)全人工种群优化和繁殖管理提供理论依据,探究中华鲟主要组织相容性复合体(MHC)IIB基因的部分遗传信息和遗传变异规律,利用特异性引物MHC IIf和MHC IIr,分别从30尾野生中华鲟个体、29尾中华鲟子一代个体和30尾中华鲟子二代个体的基因组DNA中扩增MHC IIB基因的多肽结合位点(PBR)片段,扩增产物长度为168 bp。结果表明,中华鲟野生群体30个样品的95个有效克隆中共检测出30条特异序列(单倍型),中华鲟子一代群体29个样品的96个有效克隆中共检测出38条特异序列(单倍型),中华鲟子二代群体30个样品的95个克隆中检测出36条特异序列(单倍型)。单倍型的分布及群体内遗传多样性参数分析表明,中华鲟子一代群体的MHC IIB基因遗传多样性最高,子二代中华鲟群体的MHC IIB基因遗传多样性最低。中华鲟3个群体的非同义替代(dN)与同义替代(dS)比率为1.39、1.48和1.45,非同义替换率均大于同义替换率,表明正向选择可能是中华鲟MHC IIB多态性的主要因素。     

濒危中华鲟人工群体的繁殖生物学

以1998―2008年孵出的子一代(F1)中华鲟(Acipensersinensis)为材料,研究了人工养殖中华鲟的繁殖生物学特征。结果表明:年龄10～20龄的492尾人工养殖子一代中华鲟体重为30～169 kg,体长为140～258 cm,肥满度为0.77～1.26,体长(L)与体重(W)之间的关系式为W=1×10~(–5)L~(2.9658) (R~2=0.9076,n=492)。74尾中华鲟性腺发育成熟,成熟比例为15.04%,成熟个体中雄鱼体重[(60.73±14.53)kg]和体长[(172.27±13.46)cm]均小于雌鱼体重[(88.39±29.14)kg]和体长[(193.37±18.90) cm];雄鱼最小性成熟年龄为10龄,平均为(14.96±1.93)龄,雌鱼最小成熟年龄为12龄,平均为(17.84±1.80)龄。雄鱼催产成功率为76.36%,精子快速运动时间为(49.11±13.38) s,精子寿命为(220.75±56.47)s;雌鱼催产成功率为57.89%,产卵量为(13.43±6.79)万粒,卵径(3.97±0.15)mm,卵重(0.046±0.013)g,受精率为(42.72±27.82)%,孵化率为(51.61±32.41)%,出苗量为(4.44±5.67)万尾。与野生中华鲟相比,人工养殖中华鲟成熟个体体格、繁殖力和繁殖效果均有下降趋势,人工保种面临挑战。     

超低温冷冻保存中华鲟F_1精子授精方法研究

利用超低温冷冻保存中华鲟子一代(F_1)的精液,研究4种不同激活液、2种不同的授精方式及5种不同冻精授精量对授精效果的影响。结果表明,冷冻保存365d的中华鲟F_1冻精,用养殖水激活授精效果优于4种激活液,获得(15.04±0.58)%的受精率和(14.6±0.59)%的孵化率。相同条件下,试验1、试验2和试验3的湿法受精率和孵化率分别为(18.3±1.45)%、(13.57±0.76)%、(18.65±0.42)%和(16.82±2.01)%、(11.03±0.98)%、(15.87±1.25)%,湿法授精效果均优于干法授精。用10mL中华鲟卵与不同冻精授精量进行湿法授精,精子密度3.82×109个/mL,稀释比1∶2,冻精活力(35.45±5.26)%,冻精用量0.1~0.6mL,随着冻精用量的加大,受精率和孵化率呈现上升趋势,0.6mL时,受精率和孵化率达最高,分别为(16.43±1.57)%和(14.58±1.35)%,但随着冻精用量的继续加大,其受精率和孵化率随之下降。     

中华鲟在鄂西北实现人工繁育

<正>2018年11月底,位于湖北省襄阳市谷城县庙滩镇的湖北五合特种水产养殖有限公司中华鲟繁育基地成功实现人工养殖子一代中华鲟的人工繁育,获得一批子二代幼苗。这也是该物种首次在鄂西北实现人工繁育。此前,湖北省荆州、宜昌已实现人工繁育中华鲟。农业农村部调查数据显示,长江中华鲟繁殖群体规模已由20世纪70年代1万余尾,减至目前不足100尾。人工增殖放流可使中华鲟的种群数量有所增长,促进中华鲟的有效保护。湖北五合特种水产养殖有限公司中华鲟繁育基地,由中国水产科学院长江水产研究所规划设计,属于中华鲟的     

几种因素对达氏鳇精子质量的影响

近年来,随着中国鲟鱼人工养殖业的不断发展,达氏鳇人工养殖也是一片欣欣向荣。从1999年达氏鳇人工繁殖在抚远县水产技术推广站取得成功至今,其人工养殖历经十多年。在这期间,达氏鳇人工养殖健康有序发展,并取得一些成绩。如人工养殖达氏鳇在2006年首次生产鱼子酱,并成功出口欧美多国;在2008年对养殖达氏鳇性成熟亲鱼进行人工催产试验,并取得成功。在人工养殖达氏鳇过程中,成果与问题共存。达氏鳇苗种成活率低下是其人工养殖中存在的主要问题之一。当然,苗种成活率低下原因是多方面的,有客观上的原因,也有主观方面的原因。客观原因是遗传因素造成的,包括卵子质量、精子质量及受精卵质量等。卵子和精子质量直接影响苗种成活率,在通常情况下,人们偏重于卵子质量,而忽视精子质量,这种观念是不对的。从遗传及养殖等方面来讲,精子质量和卵子质量同等重要,精子质量的好坏直接决定受精率和孵化率的高低及人工养殖苗种成活率。在进行达氏鳇人工繁殖时使用优质精液能大大提高受精率、孵化率及苗种成活率。     

花羔红点鲑驯养繁育试验与生物学特性

1989年首次将鸭绿江野生花羔红点鲑驯养性成熟,1992年人工采卵1.5万粒;1998年从第一代亲鱼采卵16万粒,受精率90％,孵化率80％,幼鱼饲养成活率50％。     

美洲红点鲑和白斑红点鲑杂交子代及其亲本早期生产性能比较

采用完全双列杂交、群体间杂交及群体内自繁等方法对美洲红点鲑（Salvelinus fominalis）和白斑红点鲑（Salvelinus leucomaenis）进行了配组繁殖,成功地获得了4类组合的子一代群体。比较了各交配组合的受精率、孵化率、成活率等生存力,结果表明：正交子一代（白斑红点鲑♀×美洲红点鲑♂）组合的受精率明显高于父本和反交子一代组合,与母本子一代组合差异不显著（p〉0．05）,孵化率和成活率与双亲自繁对照组差异不显著（P〉O．05）,高于反交子一代（美洲红点鲑♀×白斑红点鲑♂）组合。杂交子一代和亲本后代140d室内生长试验表明：不同发育阶段的正交子一代表现出杂种优势,体质量的杂种优势率为27．09％～35．66％,体长的杂种优势率为8．47％～11．25％,在体质量、体长增长量均高于双亲子一代。反交子一代群体生长发育始终没有表现杂种优势（H〈0）。     

安徽省长江水系3个水域青虾群体形态参数及生产性能比较

分别从安徽省长江水系的姑溪河、南漪湖及虾蟹混养池塘中选择表型性状优良的个体作为亲本,开展3个主要青虾群体的形态差异分析和生产性能差异试验。3个群体的形态比例参数分析表明,青虾野生群体的体长、体质量、卵重、肥满度皆显著高于池塘养殖群体;与野生群体(抱卵虾)相比,虾蟹混养池塘群体(抱卵虾)可食部分的腹部趋于小型化,表现为退化现象,姑溪河群体(抱卵虾)的腹部较南漪湖群体(抱卵虾)的宽、长,姑溪河群体雌性具有一定的抱卵空间优势;姑溪河群体(雄性)的头胸甲占整个身体的比例明显较其它2个群体的宽、长(P0.05),其经济性状较南漪湖群体(雄性)差。3个群体繁育和子一代生长比较试验结果表明,南漪湖群体的平均育苗量分别较姑溪河群体、虾蟹混养池塘群体高13.2%、45%;姑溪河群体子一代的绝对增重率、瞬时增重率分别比虾蟹混养群体高24.7%、5.3%,60 d体质量变异系数比虾蟹混养群体低21.2%。本试验为青虾的选育和种内杂交提供了理论依据。     

吉富罗非鱼与奥利亚罗非鱼自繁与杂交 F1遗传特性与抗病力分析

以吉富罗非鱼与奥利亚罗非鱼为繁育亲本,采用完全双列杂交繁育4组F1,将初始规格基本一致的4组罗非鱼饲养100 d后,运用“加性-显性”遗传分析模型,分析了4组F1罗非鱼8个生长相关性状杂种优势、遗传效应以及与性状间的相关性.结果表明:(1)F1群体平均优势为0.129 4～0.368 4.除尾柄长超亲优势较大外,其他性状的群体超亲优势较小或表现出负向超亲优势.(2)8个性状的广义遗传率(HB)为0.714 2～0.995 3,表明加性效应和显性效应对性状的遗传变异影响极显著(P＜0.01).除尾柄长外,其他性状的狭义遗传率(HN)介于0.469 4～0.737 9,表明加性遗传方差在表型方差中所占比率较高.(3)体质量、全长、体长、体高、体宽、头长、尾柄长、尾柄高性状之间表型相关在0.776 6～0.999 7范围内,而遗传相关在0.994 1～1.000 0之间,表明这些性状间都存在极显著的正相关.取样结束后,采用3.95×106 CFU/mL的海豚链球菌菌液进行腹腔感染,吉富罗非鱼自繁组F1代12 h后出现死亡,而奥利亚罗非鱼自繁组F1192 h后才出现死亡.384 h后,吉富罗非鱼自繁组F1死亡率为40％,正反交组F1分别为20％和23.3％,奥利亚罗非鱼自繁组F1死亡率最低,为6.67％.研究结果表明,除尾柄长外,杂交F1的其他性状不具备超亲优势,然而杂交可以提高选育后代的抗病力.     

Successful Hybridization of Acipenser Species Using Cryopreserved Sperm

Successful hybridization of sterlet (Acipenser ruthenus) × Siberian sturgeon (Acipenser baeri), sterlet × Russian sturgeon (Acipenser gueldenstaedti) and sterlet × European sturgeon (Acipenser sturio) was carried out for the first time using cryopreserved semen of sturgeon males and sterlet × sterlet crosses as controls. Sperm of all three species was diluted with a cryodiluent composed of 23.4 mM sucrose, 0.25 mM KCl, 30 mM Tris (pH 8.0) and 10% methanol. The samples were frozen in plastic straws in the vapor of liquid nitrogen at the height of 3 cm above the level of nitrogen for 3 min. Following thawing approximately 3000 sterlet eggs were fertilized with six straws of frozen-thawed sperm. The hatching rate with sterlet sperm was 30.6% while the hatching rate of A. ruthenus × A. baeri, A. ruthenus × A. gueldenstaedti and A. ruthenus × A. sturio hybrids was 50, 17.4 and 34%, respectively. Morphometric markers as well as random amplified polymorphic DNA (RAPD) assay was used to verify interspecific hybridization.     

A comparison of fatty acid composition and quality aspects of eggs and larvae from cultured and wild broodstock of common sole (Solea solea L.)

Eggs from a F₁ cultured broodstock of sole were compared with eggs from wild‐caught breeders throughout one spawning season, to evaluate if egg quality may be affected by culture‐related conditions. Fourteen batches of eggs from cultured broodstock and 17 batches from wild‐caught sole were compared with respect to fatty acid (FA) composition, egg size, fertilization rate and hatching rate. Based on a multivariate analysis of the FA profiles, it was possible to discriminate between culture and wild inheritance. Eggs from cultured broodstock had high levels of C20:1(n‐9), C18:2(n‐6) and C18:3(n‐3), whereas eggs from wild fish had high levels of C16:1(n‐7), C20:4(n‐6) and C20:5(n‐3). Differences in FA profiles were most likely related to dietary differences. Fertilization and hatching rates were generally low and lowest in eggs from cultured broodstock, but not related to FA composition. Larval growth of one batch from each group was compared. Larval growth was not correlated to broodstock origin, FA composition or egg or larval size. However, larval survival was significantly lower for larvae from cultured broodstock.     

Minimally invasive surgical technique for egg collection from the Persian sturgeon, Acipenser persicus

A minimally invasive surgical technique (MIST) for the removal of ovulated eggs from Persian sturgeon Acipenser persicus was tested on broodstocks caught from the wild to determine whether it affected fecundity or hatching rates compared with the traditional stripping method of killing and removing the eggs (commonly used in hatchery). Morphological parameters of females, germinal vesicle (GV) position, weight of obtained egg, number of eggs/gram, fertilization rate, and percentage of hatching during incubation were not significantly different between the MIST and traditional stripping methods. Obtained ova were 4.8 ± 0.4 kg female⁻¹ in the MIST and 4.6 ± 0.5 kg female⁻¹ in traditional stripped groups, respectively; the fertilization rate was 83.4 ± 11.2% and 80.0 ± 7.2% in groups, respectively. The results of this study showed that the minimally invasive surgical technique approach is efficient, practical, and less stressful to Persian sturgeon broodstocks during artificial propagation than other reported egg collection procedures.     

人工养殖西伯利亚鲟精子超低温冷冻保存研究

研究了人工养殖西伯利亚鲟精子的生物学特征及超低温冷冻保存方法。西伯利亚鲟的产精量为113.67±39.86 ml,精子密度为(6.49±3.10)×108/ml,精子活力为(85.4±9.5)%,精子寿命为353±23 s。精子密度与精子快速运动时间、精子寿命之间均存在线性相关,用方程分别表示为:y=1.0384x+1.5089(R2=0.7325);y=2.9069x+74.289(R2=0.6967)。结果表明精子密度可作为一项精子质量评价的标准。通过比较西伯利亚鲟精子在不同稀释液、不同抗冻剂和抗冻剂浓度、降温速率、解冻温度下的保存效果,结果表明:配方2作为稀释液,18%甲醇作为抗冻剂,二步法超低温(-196℃)冷冻保存精子,40℃水浴解冻取得最好的冻后活力,解冻后活力为(51.8±5.8)%。西伯利亚鲟授精的最佳精卵比为106∶1。在此精卵比下用冻精授精分别得到了(72.3±3)%的受精率和(52.9±4.1)%的孵化率,其中受精率与鲜精没有显著性差异,孵化率与鲜精有显著差异(P<0.05)。     

近交对长牡蛎幼虫和稚贝生长与存活的影响

分别以2010年通过2个野生个体进行交配获得的A01全同胞家系和2011年通过A01家系子代进行交配获得A02全同胞家系为亲本,在2013年6月采用同时建立全同胞交配子一代F1(F=0.250)、全同胞交配子二代F2(F=0.375)及设置对照组(F=0)的方法,研究在相同环境条件下,不同实验组的受精率与孵化率以及近交对长牡蛎幼虫期、稚贝期生长和存活的影响,并初步探讨近交代数与近交衰退的关系。结果发现,各组的受精率均在90%以上,除F2组外其余2组的孵化率也在90%以上;幼虫阶段,F1组和F2组的壳高与壳长均从12日龄出现衰退(近交衰退系数,inbreeding depression coefficient,IDC0),且F2组壳高的近交衰退系数均小于同日龄F1组壳高的近交衰退系数;F1组和F2组的存活率在整个幼虫期间均出现衰退,且F1组和F2组存活率的近交衰退系数均随着幼虫日龄的增加而逐渐减小。稚贝阶段,F1组和F2组的平均壳高在各日龄均表现出近交衰退(IDC0),且F2组壳高的近交衰退系数均小于相同日龄F1组壳高的近交衰退系数;3个实验组的平均壳长在整个稚贝阶段无显著性差异;F1组和F2组存活率的衰退在不同日龄始终存在(IDC0),且随着稚贝日龄的增加其衰退程度逐渐加大。研究结果为长牡蛎选择育种和遗传改良提供了基础资料。     

Genetic structure and genetic relatedness of a hatchery stock of Senegal sole (Solea senegalensis) inferred by microsatellites

Solea senegalensis is a fish species in an early stage of domestication. A commercial hatchery in southern Spain experienced a dramatic failure in spawning and embryo survival, after incorporation into the broodstock of fish reared in their hatchery. To assess the impact of management on the stock quality, a population genetics study was made of adult broodstock present at this hatchery in 2000. The broodstock was composed of a group of fish of wild origin and two more groups from F₁ progeny. A set of eight microsatellite loci was used to compare genetic variability among the three groups and to establish the relationships between pairs of individuals within each group.Individuals from F₁ origin showed a substantial reduction in genetic variability when compared to those from the wild. There was a greater than 50% decrease in the number of alleles per locus corrected by sample size and 16% and 26% reductions in H_e values in the two F₁ groups, respectively. The degree of genetic relationship between individuals, evaluated by the relatedness estimator, rxy, and by graphical approaches, revealed a high proportion, almost 75%, of full-sibs and half-sibs in both F₁ groups, which might account for the reduction in overall variability. The high proportion of siblings also suggests a reproductive pattern in this stock in which few individuals breed successfully. This mating behaviour, along with factors inherent to selection and management systems, might be responsible for the negative effects on the reproductive capacity of the stock.     

Use of minimally invasive surgical technique for egg removal from the beluga,Huso huso

Reuse of sturgeon broodfish for propagation could provide an opportunity to ease fishing pressure on the wild stocks of these valued species. A minimally invasive surgical technique (MIST) for the removal of ovulated eggs from the beluga, Huso huso, was tested on broodfish caught from the wild to determine whether it affected fecundity or hatching rates when compared with the traditional stripping method that involves killing the fish and removing the eggs. In comparison with the traditional procedures, MIST is rapid: it can be performed in between 8 and 15 min per fish. Morphological parameters of female beluga, germinal vesicle position, weight of obtained eggs, fertilization rate, and percentage hatching during incubation were not significantly different between the MIST and the traditional procedure. The fish remained healthy 4 weeks after surgery. The final results of this study showed that the MIST approach is efficient, practical, and less stressful to beluga broodfish during artificial propagation than other reported egg collection procedures.     

Kurokura Solution as Immobilizing Medium for Spermatozoa of Tench (Tinca tinca L.)

This study tested KUROKURA solution (Kurokura et al., 1984, Aquaculture 37, 267–274) and its modifications (by increasing NaCl content to 160, 180 and 200 mM) on immobilizing properties for sampling and short-term preservation of potential motility of tench spermatozoa. The immobilizing solution is used because, when collected, the sperm of most samples is contaminated by urine, causing spermatozoa to be of poor quality, with low motilities and velocities (almost 0), thus resulting in a worsened fertilization and hatching rate. Sperm was sampled with a syringe containing an immobilizing solution (IS), allowing an IS:sperm ratio of 2:1, under aerobic conditions at 0–4°C. This sperm solution was stored for 10 h and untreated sperm was collected prior to fertilization as a control. Spermatozoa quality was evaluated for the cell motility and velocity parameters and also for fertilization ability and hatching rate. Results obtained for tench sperm motility, velocity, fertilization and hatching rate showed that only sperm collected in the various immobilizing solutions can be successfully used for artificial insemination and preservation after 10 h at 0–4°C. The best immobilizing solution was found to be KUROKURA 180 (180 mM NaCl, 2.68 mM KCl, 1.36 mM CaCl₂· 2H₂O and 2.38 mM NaHCO₃), giving a fertility and hatching rate of 41%, with no change in rates after 10 h storage of sperm. Control sperm without immobilizing solution showed a fertilization and hatching rate of only 6–7%.     

草鱼野生与选育群体遗传变异微卫星分析

为探究经过2个选育世代后选育群体遗传多样性和遗传结构的变化,实验采用多重PCR技术对4个野生草鱼群体(邗江、九江、石首、吴江)和2个选育群体(F1和F2)进行了微卫星序列遗传变异分析。结果显示,6个草鱼群体遗传多样性水平较高,2个选育群体除了平均等位基因数外,其他遗传多样性参数均小于4个野生群体。哈迪—温伯格平衡(Hardy-Weinberg equilibrium)检测显示,在120个群体—位点组合中有62个位点显著偏离哈迪—温伯格平衡,62个群体—位点组合中只有11个组合其近交系数值为负值,其余的51个组合的Fis均为正值。6个草鱼群体AMOVA分析结果显示,3.75%的变异来自于群体间,96.25%的变异来自于群体内,整体的遗传分化指数值为0.038。进一步分析各个群体间Fst,只有石首群体与F1、F2群体之间的Fst大于0.05,处于中等分化,其余群体间分化程度较低,且F2群体与4个野生群体之间Fst比F1群体与4个野生群体之间的Fst大。奈氏标准遗传距离分析结果显示,2个选育群体与野生群体之间的遗传距离大于野生群体之间的遗传距离。基于Dn建立的UPGMA系统发育树得出了相同的结果,即2个选育群体与野生群体之间的亲缘关系比4个野生群体之间的亲缘关系要远。研究表明,经过2个世代选育后,相比4个野生群体,2个选育群体遗传多样性虽有部分下降,但仍处于较高的水平,2个选育群体的遗传结构已发生变化,但其遗传分化程度尚不明显。本研究结果为制定出更加完善有效的选育方案提供了重要参考。