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1.
红鳍东方鲀(Takifugu rubripes)生长性状的遗传参数估计   总被引：1，自引：0，他引：1       下载免费PDF全文
通过人工受精的方法获得红鳍东方鲀8个半同胞家系(16个全同胞家系),共测量了790尾红鳍东方鲀8个半同胞家系(16个全同胞家系)135日龄和200日龄的体质量和体长。将135日龄生长性状作为协变量构建3个动物模型,模型(1)包含加性遗传效应、母本遗传效应和全同胞效应;模型(2)包含加性遗传效应和母本遗传效应;模型(3)包含加性遗传效应和全同胞效应。利用DMU软件,采用平均信息约束极大似然法估计各模型中性状的方差组分,用似然比检验法进行不同模型的差异检验。选择最优模型估计红鳍东方鲀200日龄生长性状的遗传参数。结果表明,母本遗传效应对200日龄红鳍东方鲀生长性状无显著影响,确定模型(3)为最优模型。200日龄红鳍东方鲀,体质量和体长的遗传力分别为0.16和0.14,全同胞效应比率分别为0.12和0.13。研究表明,红鳍东方鲀生长性状具备一定的选择潜力,应用家系选育方法能够获得较好的遗传进展。  相似文献   

2.
通过人工受精的方法获得红鳍东方鲀8个半同胞家系(16个全同胞家系),共测量了790尾红鳍东方鲀8个半同胞家系(16个全同胞家系)135日龄和200日龄的体质量和体长。将135日龄生长性状作为协变量构建3个动物模型,模型(1)包含加性遗传效应、母本遗传效应和全同胞效应;模型(2)包含加性遗传效应和母本遗传效应;模型(3)包含加性遗传效应和全同胞效应。利用DMU软件,采用平均信息约束极大似然法估计各模型中性状的方差组分,用似然比检验法进行不同模型的差异检验。选择最优模型估计红鳍东方鲀200日龄生长性状的遗传参数。结果表明,母本遗传效应对200日龄红鳍东方鲀生长性状无显著影响,确定模型(3)为最优模型。200日龄红鳍东方鲀,体质量和体长的遗传力分别为0.16和0.14,全同胞效应比率分别为0.12和0.13。研究表明,红鳍东方鲀生长性状具备一定的选择潜力,应用家系选育方法能够获得较好的遗传进展。  相似文献   

3.
为了丰富海参池塘养殖的混养种类,实验对刺参和红鳍东方鲀的生态混养效果进行了研究。结果显示,经过100 d的混养实验,红鳍东方鲀平均日增重率为1.07 g/d,特定生长率为4.06%/d,混养组与单养组红鳍东方鲀没有显著差异;但混养条件下刺参的生长状况显著优于单养条件下刺参的生长状况。与红鳍东方鲀混养组刺参平均日增重率为(0.11±0.04)g/d,特定生长率为(0.67±0.20)%/d。单养组刺参平均日增重率为(0.04±0.02)g/d,特定生长率为(0.35±0.19)%/d。研究表明,刺参池塘混养红鳍东方鲀模式下,红鳍东方鲀在正常快速生长的同时,可以有效促进刺参的生长,研究结果可以为刺参池塘的生态复合养殖提供参考依据。  相似文献   

4.
研究水温对鱼类生长影响,阐明最适生长温度及其机制,具有重大理论和实践意义。在鱼类的能量收支中,摄食是唯一的能量收入部分,在影响鱼类摄食量的诸多因子中温度和体重是最重要的两个。本试验设T=20℃、24℃、28℃、32℃四个温度梯度组,分两期进行：Ⅰ期研究在这四个不同温度下红鳍东方鲀幼鱼体重增长和全长增长的情况,Ⅱ期研究在这四个不同温度下不同体重红鳍东方鲀幼鱼对最大摄食量的影响。结果发现在Ⅰ期中当水温T=28℃时红鳍东方鲀幼鱼体重增长和全长增长最快,日增重率和日增长率分别为1.684,0.588。在T=20℃和T=24℃时体重和全长的增长率随温度的升高而逐渐增大,超过28℃时开始降低。在Ⅱ期试验中发现红鳍东方鲀幼鱼最大摄食量随体重的增大而增加,最大摄食量随温度的变化情况为：在试验水温为20～28℃范围内,二者呈正相关,超过28℃度时呈负相关。综合两期试验研究得出28～29℃是适合红鳍东方鲀幼鱼生长的最适温度。  相似文献   

5.
温度对红鳍东方鲀能量收支和生态转化效率的影响   总被引：2，自引：0，他引：2  
以玉筋鱼为饵料生物和最大摄食水平条件下,采用室内流水式实验,测定了不同温度下(13、16、19和25°C)红鳍东方鲀(平均体重为37.1±7.7g)的生态转化效率和能量收支各组分.结果表明,红鳍东方鲀的最大摄食率、吸收率、排泄能和总代谢能均随温度上升呈增长趋势.以湿重计算的特定生长率(SGRw)和生态转化效率(ECEw)则呈现先随温度增长而后下降的趋势,其与温度之间的关系可用二次方程描述.由回归方程计算出的特定生长率最大值出现在23.52℃,生态转化效率最大值出现在18.95℃.方差分析表明,红鳍东方鲀的能量分配模式随温度变化显著.排泄能分配率和代谢能分配率占摄食能的绝大部分67.8%～81.7%,随温度升高呈"U"形变化趋势,最低出现在16℃;生长能分配率则与之相反,最高分配率出现在19℃.不同温度下红鳍东方鲀的代谢能占了同化能的61.1%～73.5%,生长能占13.2%～23.2%.可见红鳍东方鲀基本上属于中等生长效率、中等代谢消耗型鱼类.  相似文献   

6.
杜佳垠 《齐鲁渔业》2003,20(9):22-22
1 发生 在我国,红鳍东方鲀盾纤虫病最早于2000年初春由笔者确认于大连1家企业水槽越冬养殖的1龄红鳍东方鲀(杜佳垠,2000)。尔后,笔者在大连4家企业先后确认10例红鳍东方鲀盾纤虫病。其中,包括2002年初夏1家企业水槽培育1月龄红鳍东方鲀稚鱼盾纤虫病、链球菌病并发症;2002年晚春1家企业水槽越冬养殖1龄和2龄红鳍东方鲀盾纤虫病、冈本异沟吸虫病、链球菌病并发症;2002年初冬1家企业水槽越冬养殖当年红鳍东方鲀盾纤虫病、链球菌病并发症和2年红鳍东方鲀盾纤虫  相似文献   

7.
养殖密度是影响养殖水体水质和鱼类生长性能的重要因素。通过红鳍东方鲀(Takifugu rubripes)循环水养殖试验和硝酸盐氮急性处理试验,分别研究不同养殖密度(12.5~20.0 kg/m^3)和不同硝酸盐氮质量浓度(1.0、25.0、100.0和150.0 mg/L)对养殖水体水质、红鳍东方鲀生长性能、应激反应和抗氧化状态的影响。结果显示:不同养殖密度对红鳍东方鲀养殖水体的pH、氨氮和亚硝酸盐氮质量浓度无显著性影响,但较高密度会导致硝酸盐氮质量浓度显著升高,最高升至24.5 mg/L。在较高养殖密度条件下,红鳍东方鲀的生长性能(终体质量、特定增长率和饲料转化率)和抗氧化能力(总抗氧化能力、超氧化物歧化酶、谷胱甘肽过氧化物酶)较弱,但其脂质过氧化(丙二醛)和应激反应(葡萄糖、乳酸和皮质醇)较强。此外,在硝酸盐氮急性处理试验中,红鳍东方鲀未出现死亡。当硝酸盐氮质量浓度为100.0和150.0 mg/L时,红鳍东方鲀抗氧化能力较弱,而应激反应较强。综上,当养殖密度为16.5 kg/m^3时,红鳍东方鲀的生长和抗氧化状态较好,且应激压力较小,这表明在较高密度条件下,养殖水体硝酸盐氮质量浓度的升高不是引起鱼类生长抑制的主要原因。  相似文献   

8.
伪雌鱼的培育是红鳍东方鲀(Takifugu rubripes)全雄制种技术研发的关键环节之一,然而外源雌激素诱导获得的伪雌鱼表现出卵巢发育迟滞,降低了其育种价值和效率。为探讨红鳍东方鲀伪雌鱼卵巢发育迟滞的调控机制,本研究从孵化后20日龄开始,用10 μg/L 17 β-雌二醇(E2)浸泡红鳍东方鲀稚幼鱼,每天浸泡1次,每次2 h,至90日龄结束。在90、180和330日龄分别采集处理组(10 μg/L E2)遗传雄性幼鱼和对照组(0 μg/L E2)遗传雌性幼鱼,比较两组幼鱼性腺的组织学和形态学变化特征、下丘脑-垂体-性腺轴相关激素(FSH、LH、E2和17α, 20βOH-PROG)和基因(fshr、lhr、erα、erβ1、erβ2)及脂质积累相关基因(lpl和vldlr)的变化规律。结果显示: 10 μg/L E2可将遗传雄性幼鱼全部诱导为伪雌鱼,且伪雌鱼直至330日龄未二次反转为间性或者雄性,但其性腺系数、卵母细胞数量及卵黄生成前期的卵母细胞面积均显著小于对照雌鱼。此外, 90日龄伪雌鱼的lhr和pgr的表达量显著高于同期对照雌鱼,而17α, 20β-PROG的含量及fshr的表达量显著低于对照组;180日龄伪雌鱼的vldl表达量显著低于对照组;330日龄伪雌鱼的激素含量及基因表达量没有显著差异。综合分析伪雌鱼性腺发育的形态学、组织学和性腺轴相关激素及基因变化规律可见,足够浓度的外源E2能够诱导并维持伪雌鱼的卵巢特征,但E2浓度过高,一方面可能抑制fshr和vldlr基因的表达,从而影响脂质在卵黄生成早期卵母细胞中的积累,导致红鳍东方鲀伪雌鱼卵母细胞生长迟缓;另一方便,高浓度E2抑制伪雌鱼卵原细胞减数分裂的启动,是导致红鳍东方鲀伪雌鱼卵母细胞数量较少的原因之一。  相似文献   

9.
利用封闭呼吸室对同一日龄、不同规格的红鳍东方鲀、菊黄东方鲀和菊黄东方鲀(♀)×红鳍东方鲀(♂)杂交F1代幼鱼进行耗氧率和临界窒息点的研究。试验结果表明,水温14.8～15.6℃时,体质量(37.24±3.64)g的红鳍东方鲀幼鱼耗氧率为(0.3385±0.0161)mg/(g.h),体质量(14.45±1.08)g的菊黄东方鲀幼鱼耗氧率为(0.2327±0.0241)mg/(g.h),体质量(27.96±1.38)g的杂交F1代东方鲀幼鱼耗氧率为(0.2282±0.0219)mg/(g.h);同一日龄不同规格红鳍东方鲀、菊黄东方鲀和杂交东方鲀幼鱼的耗氧量分别为(12.5243±0.6720)、(3.3544±0.2975)、(5.8469±0.9537)mg/(h.尾);3种东方鲀的耗氧率呈明显的昼夜节律,白天平均耗氧率显著高于夜晚。水温为14.8～15.6℃时,红鳍东方鲀、菊黄东方鲀及杂交东方鲀幼鱼的临界窒息点分别为0.665、0.882mg/L和0.774mg/L。  相似文献   

10.
为了比较红鳍东方鲀(Takifugu rubripes)雌、雄个体的形态差异,基于主成分分析、逐步判别分析和T检验的方法,以红鳍东方鲀雌、雄群体的17个比例性状为分析对象进行研究。主成分分析构建了3个反映形态特征信息的综合性指标—主成分1、主成分2和主成分3,贡献率分别为46.776%、27.668%和7.122%,3个主成分累积的贡献率为81.566%,两个群体之间存在明显的偏离;判别分析结果显示,根据各变量对判别函数的贡献大小,筛选出两个比例性状,即体宽/体长、体周长2/体长,利用这两个性状建立起红鳍东方鲀的雌、雄判别模型,对雌、雄共72个个体的判别准确率为81.9%;T检验结果显示,体宽/体长在红鳍东方鲀两性群体间差异极显著(P0.01),体周长2/体长在红鳍东方鲀两性群体间差异显著(P0.05)。综合分析实验结果表明,红鳍东方鲀雄性与雌性相比,体形较宽,体周长2较长。红鳍东方鲀雌、雄的形态差异为繁育和选育过程中的性别鉴定提供了新的方法和理论依据。  相似文献   

11.
水温对半滑舌鳎性腺组织发育的影响   总被引：1，自引：0，他引：1  
汪娣  田永胜  陈松林 《水产学报》2012,36(2):262-271
探讨了不同温度(19,21,23,25和27 ℃)对半滑舌鳎的性腺组织发育的影响。在受精后39～106 d对半滑舌鳎进行温度控制处理,通过石蜡组织切片,对半滑舌鳎早期性腺分化发育进行组织学观察。发现在19 ℃饲养条件下,受精后46 d(pfd46)半滑舌鳎性腺原始生殖细胞数量增加,有分化成卵巢的倾向;在该条件下,pfd82半滑舌鳎性腺开始分化为精巢。pfd82时,27 ℃条件下的幼鱼卵巢中卵原细胞数目大量增殖;精巢中精小叶多而密,结缔组织间隔清晰。pfd129时,27 ℃处理的幼鱼卵巢发育到Ⅱ期,其他温度处理组仍处于Ⅰ期卵巢,但随着温度的提高,卵巢中卵母细胞数目增多,且由散乱分布变为有序的排列在卵巢小叶中;精巢中贮精囊数量增多,囊腔中精子增多。pfd142时,高温处理组幼鱼性腺发育最快,其Ⅱ期卵巢中卵母细胞数目最多,精巢中后期生精细胞偏多,精子几乎分布到各个精小叶中,且贮精囊结构发达,内纳高密度精子,在周围输精管中也分布着精子。结果表明,温度影响了半滑舌鳎性腺发育程度,二者呈现线性关系,在适当温度范围内,性腺发育速度随着温度升高而加快。  相似文献   

12.
Female summer flounder grow considerably faster than males, and rearing temperature has been shown to influence sex differentiation in related species. The present studies were conducted to examine sex differentiation of post‐metamorphic juveniles reared at temperatures conducive for commercial production. In experiments 1 and 2, offspring produced from crosses with meiogynogenetic, sex‐reversed males and normal females were raised at 14, 16 or 18°C for ≥300 days or 12°C for 30, 60 or 120 days and then transferred to a male‐determining temperature (21°C). In all cases, the fish developed predominantly as phenotypic males (≥74%). In a third experiment, offspring produced from crosses with normal males and females were reared at 15, 17 and 19°C for 111, 227 and 278 days and then transferred to 21°C. Most fish (≥92.1%) developed as phenotypic males irrespective of rearing temperature or length of exposure. Several hypotheses are proposed for these findings and further research is necessary to understand the sex‐determining mechanisms in this species before the economic advantages associated with sexually dimorphic growth can be realized.  相似文献   

13.
2008年4月16-28日在浙江湖州地区进行了花于水温15℃条件下的人工催产生产性试验。用常规催产剂和方法,催产花亲鱼540尾,其中雌亲鱼355尾、雄亲鱼185尾。试验结果表明:排卵率为91.5%,催产效应时间为29.5 h,群体排卵时间为2.5 h;受精率为98.7%;孵化鱼苗(下塘鱼苗)380万尾。与常规生产水温17～18℃以上催产情况比较,在水温15℃条件下,花也完全可以进行人工催产;除效应时间和孵化时间延长及卵膜难以溶解外,其排卵率、受精率、群体排卵时间和孵化率等均无明显差异。  相似文献   

14.
The timing of primordial germ‐cell (PGC) migration with regard to the gonadal anlagen, gonad formation and sex differentiation was examined histologically in the chub mackerel (Scomber japonicus) at 5–190 days post hatching (dph). At 5 dph, PGCs appeared on the peritoneal epithelium surface or in the mesentery, on the dorsal side of the abdominal cavity. By 10 dph, stromal cells around the PGCs proliferated. The gonadal primordium was formed by 15 dph. The gonadosomatic index was 0.01% at 30 dph and increased thereafter (0.32% in females and 0.04% in males at 160 dph). Ovarian differentiation occurred at 30–40 dph, indicated by ovarian cavity formation (elongation and fusion of the upper and lower ovarian edges). Meiosis was subsequently initiated. A few meiotic oocytes surrounded the cavity at 50 dph; most were in the perinucleolus stage at 60 dph and attained a diameter of 60–70 μm at 190 dph. Testicular differentiation occurred at 30 dph, indicated by the formation of the sperm duct primordium. Spermatogonia gradually proliferated, developing into spermatocytes at the chromatin–nucleolus stage (after 90 dph) and subsequently into spermatids and spermatozoa (160 dph). These data could aid the development of seeding and cell‐engineering technologies for scombrid fish.  相似文献   

15.
To produce a monosex female population of European sea bass Dicentrarchus labrax, fry were fed dry diets containing dosages of 12.5, 25, and 50 mg/kg food of either the natural estrogen estradiol-170β(E2) or the synthetic estrogen 17α-ethynylestradiol (EE2) for 60 d starting at 88 d post-hatch (dph). A complete feminization (100%) was achieved in all E2-treated groups at the age of 11 mo (330 dph). All affected fish had ovaries similar in size and histological structure to those of control females. In the E2-treated groups, feminized fish were heavier and longer than untreated controls (males and females combined). In control groups females exhibited significantly higher body weight and total length than males. Untreated females from control groups and females from the group treated with E2 at 12.5 mg/kg food had similar body weight, suggesting that in sea bass growth is related to phenotypic sex. In the Entreated groups, survival rates were similar to those of the control fish. A relatively high percentage of females was obtained in the EE2-treated groups (from 38.6 to 96.5%). However, the gonadal development in these fish was significantly suppressed and a dose-dependent reduction of gonadal sizes was evident. Treatments with the EE2 (12-5, 25, and 50 mg/kg food) resulted in many fish having abnormal (2.9-5.4-39.8%, respectively) and sterile (0.6-6.0-21.6%, respectively) gonads. Effects also included significantly lower weight and shorter length when compared with controls. Furthermore, fish fed with EE2 at the dosage of 50 mg/kg food had high mortality rate. A simple protocol was developed for the complete feminization in sea bass in which the fry (80-100 dph) were fed to satiation two times daily with a diet containing 12.5 me of E2/ks food for a period of 60 d.  相似文献   

16.
Gene transfer has offered a new tool for the development of improved fish strains for aquaculture. Monosex fish populations could minimize the impact of genetically modified organisms in the environment. In Oreochromis aureus, the use of pseudofemale spawners (sex-reversed male with a female phenotype) is an alternative technique for producing genetically male tilapia offspring. O. aureus fry were treated with 17β-estradiol at 100 mg/kg of food for 45 days. We obtained 77.1% females and 45.9% in the control group. Females randomly taken from the treated group were crossed with normal males. Fry from pseudofemales producing more than 90% male progenies were submitted to 17 β-estradiol treatment to obtain F2 pseudofemales. The results of the sex-reversal were low and variable ranging between 66.0 and 84.3% females. F2 pseudofemales were crossed with transgenic males from the F70 line (O. aureus × O. urolepis hornorum) and non-transgenic (O. aureus) males. The sex ratio of progeny of F2 pseudofemale deviated significantly (P < 0.01) in favor of males in the crosses with transgenic (90.2%) and non-transgenic (89.3%) males compared to the results observed with normal females (51.0 and 52.3%, respectively). The mean fry production with pseudofemales (per m2/day) was similar to the normal females in the crosses with transgenic and non-transgenic males. To our knowledge this is the first report on the production of a near monosex population in genetically modified fish.  相似文献   

17.
Oral administration of 17β-oestradiol at 20 mg/kg diet for a period from 0 to 60 days following “swim-up” resulted in the sex reversal of male brook trout and the production of essentially all-female populations. The gonads of these animals were indistinguishable from the ovaries of untreated fish.Oral administration of this hormone at the same concentration but for the period from 0 to 40 days resulted in a population which comprised 67% females, 21% males and 12% bisexual animals.Within the control group, the growth rate of males was significantly greater than that of females. Growth in the all-female stocks produced by dietary oestradiol administration (0–60 days) was significantly lower than that of the untreated population taken as a whole but was identical to that of the control females.The growth of brook trout during the first year was closely comparable to that of rainbow trout reared under identical conditions. During the second year, the growth of the rainbow trout exceeded that of the brook trout. At 19 months of age, all the animals in the control and oestradiol treated brook trout populations were fully mature; maturity in the rainbow trout was substantially confined to males.  相似文献   

18.
Immersion of 1‐day‐old Silurus asotus (Linnaeus) larvae in 50, 100 or 200 μg L?1 oestradiol‐17β for 15 days altered gonad differentiation and gonadal morphology. The survival of the group immersed at the highest dose (200 μg L?1) was reduced significantly (86%), whereas survival of the groups immersed at the lower doses was as high as that of untreated controls (94%). The sex ratio of the untreated group was close to 1:1 (female–male); however, the incidence of females was significantly higher in groups immersed in doses of 50, 100 and 200 μg L?1, i.e. 86%, 92% and 99.4%, respectively. Ovarian morphology of feminized individuals was different to that of the controls; the ovary was morphologically rather similar to testis although it contained fully matured oocytes. Morphological changes in genital organs were also noted in fish exposed to oestradiol‐17β the shape and size of genital papilla were intermediate between those of normal male and female. During a 4‐month growth trial after the exposure, the feminized fish showed significantly improved growth performance over normal genetic males (P < 0.05), although the growth was not equal to that of normal genetic females (P < 0.05).  相似文献   

19.
Witch flounder Glyptocephalus cynoglossus has recently been identified as a candidate species for aquaculture in the northeastern United States and the Canadian Atlantic Provinces. This study investigated the optimal temperatures for witch flounder larval first feeding and for long term larval culture from hatching through metamorphosis. Maximum first feeding occurred between 15.0 and 16.2 C. Larvae did not survive beyond first feeding when reared at mean temperatures of 5.1, 10.4, or 19.5 C and were unable to initiate feeding at mean rearing temperatures below 6.0 C. At a rearing temperature of 15.0 C in 16-L tanks, mean larval survival to 60 days post hatch (dph) was 14.1%. Mean overall length-specific growth rate for larvae reared to 60 dph at 15.0 C was 3.5%/d and mean absolute growth was 0.62 mm/d. Subsequent larval growth at 15.6 C began to taper off towards 70 dph at the onset of weaning which overlapped with larval metamorphosis. Growth plateaued at 85 dph, followed by a rebound between 90 and 95 dph. Survival was 100% when weaning onto a dry, pelleted diet was initiated at 70 dph with a 10-d live diet co-feeding period. These results are favorable and encourage the further pursuit of commercial witch flounder culture.  相似文献   

20.
The effect of water temperature on growth and food intake of juvenile peled Coregonus peled was tested with specimens of initial age 75 days and 230 days posthatching (dph). The 75‐day group (initial body weight 0.6 ± 0.04 g) were reared for 63 days and 230‐day group (initial body weight 13.75 ± 2.93 g) for 42 days at temperatures of 13, 16, 19, 22 and 25°C under 12:12 L:D photoperiod. The optimal temperature range for the 75 dph fish was found to be 19–22°C. The fish reached final mean weight of 9.7 ± 2.5 g at 19°C and 9.0 ± 2.7 g at 22°C. Final mean weight of 230 dph fish did not differ significantly among temperature groups. Mortality increased at higher temperatures, with the critical temperature of 25°C for both age groups. Maximum food intake (19.0 ± 4.7, 18.8 ± 5.2, 18.6 ± 4.6 g kg?1biomass) was observed in groups reared at temperatures of 19, 22 and 25°C with no significant differences among groups.  相似文献   

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