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1.
三倍体湘云鲫性腺指数分析   总被引:17,自引:2,他引:15       下载免费PDF全文
刘少军 《水产学报》2002,26(2):111-114
对三倍体湘云鲫和作为对照的二倍体日本白鲫的性指数进行了比较分析。三倍体湘云鲫的卵巢指数、精巢指数、脂肪型“性体”指数都分别低于日本白鲫的卵巢指数、精巢指数及两者的平均值,日本白鲫的卵巢指数是湘云鲫卵巢指数的2.85倍,日本白鲫的精巢指数是湘云鲫精巢指数的1.94倍,日本白鲫卵巢和精巢的平均指数是湘云鲫脂肪型“性体”指数的5.60倍,具脂肪型“性体”的湘云鲫生长速度最快,其次是雌性湘云鲫,最后是雄性湘云鲫,根据性体指数对照,说明三倍体湘云鲫的性腺发育受到不同程度的抑制,其中脂肪型“性体”中生殖细胞的发育完全被抑制;卵巢发育的抑制程度大于精巢,其主要抑制效应表现在具有卵黄的卵母细胞的大幅度减少,无论从生殖角度还是生长角度来考虑,具有脂肪型“性体”的湘云鲫是最理想的不育三倍体鱼。  相似文献
2.
虾夷扇贝海区采苗技术初步研究   总被引:8,自引:4,他引:4  
2005—2006年,在大连旅顺沿海进行了虾夷扇贝海区采苗试验。试验结果为:2005年月亮湾海区采苗密度,第1批为231枚/袋,第2批为423枚/袋;2006年月亮湾海区采苗密度为242枚/袋,董砣子海区为456枚/袋。生殖腺指数等调查结果表明,长海县各海区虾夷扇贝开始产卵时间在3月末4月初。虾夷扇贝浮游幼虫附着高峰期出现在5月底。  相似文献
3.
珠江水系大眼鳜的繁殖生物学   总被引:7,自引:0,他引:7       下载免费PDF全文
王广军 《水产学报》2006,30(1):50-55
为了研究大眼鳜(Siniperca kneri)的繁殖生物学,对珠江水系的322尾大眼鳜性成熟样本进行了生物学指标测量。根据性腺成熟系数周年变化情况和成熟度周年分布,可以推断大眼鳜的生殖季节为4-8月份,产卵旺季为5-6月份。绝对怀卵量随体长、体重、年龄的增加而增加,在11036~106022粒之间,相对怀卵量则不随体长、体重、年龄的变化而变化,而是保持在每克100粒左右。在水温24~25℃时,受精卵经过69h23min孵化出膜。  相似文献
4.
中国对虾卵巢发育过程中脂肪酸组成的分析及比较研究   总被引:5,自引:0,他引:5  
通过分析中国对虾亲虾在卵巢发育的不同阶段的卵巢、肝胰脏和肌肉的脂肪酸组成来评估中国对虾在性腺成熟过程中对脂质的需要。从中国对虾亲虾不同组织的脂肪酸组成可见,棕榈酸(16:0)、棕榈油酸(16:1ω7)、油酸(18:1ω9)、二十碳五烯酸(20:5ω3,EPA)及二十二碳六烯酸(22:6ω3,DHA)占主要比例,这与其它海洋甲壳类的脂肪酸组成相类似。中国对虾亲虾的主要脂肪酸组成比例与日本对虾亲虾的主妥脂肪酸组成比例相近似。中国对虾亲虾在不同的卵巢成熟期同一器官中的主要脂肪酸组成比例没有明显的差别,而不同组织的主要脂肪酸组成中都含有大量的ω-3系列的高度不饱和脂肪酸。从成熟卵巢的脂肪酸组成中含有高比例的EPA、DHA含量可见,EPA、DHA在亲虾性腺发育过程中的必需性。  相似文献
5.
6.
Abstract The spawning periodicity of silver pomfret, Pampus argenteus (Euphrasen), was investigated against a background of conflicting evidence on the onset of spawning in this species. Contrary to the existing view that silver pomfret in Kuwait waters begin to spawn in March–April, evidence is presented that indicates a delay in spawning until May. Only an insignificant level of spawning takes place in April which, from the management point of view, may be ignored. The species has a prolonged spawning period extending from May to August in females, although the males mature in April and ripe specimens are encountered in monthly samples until September. There are two spawning peaks, the first one in May and the second in August.  相似文献
7.
使用鲤脑垂体和HCG对雌性日本鳗鲡人工催熟,用临床医学检验方法,测定分析了雌性日本鳗鲡卵巢发育过程中,血清总蛋白(TP)、血清甘油三脂(TG)、血清胆固醇(TC)、血糖(Glu)、血钙(Ca)和血清无机磷(P)6项生化指标的水平及变化趋势,并与对应的不同卵巢发育阶段的性腺成熟系数(GSI)进行比较分析。结果表明,84d的注射过程中,实验组的性腺逐渐成熟,GSI显著升高,第12针时达到46.32%±1.75%;而对照组性腺GSI一直在2.42%±0.18%。实验组和对照组血清TP水平相对平稳,各组变化无显著差异(P>0.05)。实验组和对照组血脂在56d前差异显著(P<0.05):实验组血清TG,TC一直维持较高水平,平均分别为(12.67±2.83)mmol/L和(15.54±3.01)mmol/L;对照组TG和TC一直下降且水平较低,平均分别为(6.33±4.14)mmol/L和(8.53±3.30)mmol/L。实验组和对照组血清Glu均在实验初的较低水平基础上持续上升。相关分析表明,实验组血清TG与GSI水平极显著负相关(r=0.732,n=6,P<0.01)。实验组血清Ca与GSI(r=0.961,n=6,P<0.01),血清P与GSI(r=0.775,n=6,P<0.01)都呈现出极显著的相关性:血清Ca和P在28d后持续上升,GSI逐渐增大。对照组中的血清Ca和P水平则一直维持在一个较低的水平。研究结果表明:雌性日本鳗鲡卵巢发育与其脂类代谢密切相关,无机离子(Ca,P)在此过程中起到重要作用。利用繁殖鱼体营养代谢特点,检测日本鳗鲡血脂或血清Ca和P水平,可成为初步判断雌性日本鳗鲡发育情况的新方法。  相似文献
8.
东海中部日本鲭(Scomber japonicus)产卵群体繁殖力特征   总被引:1,自引:0,他引:1       下载免费PDF全文
利用2010–2012年春季在东海中部获得的日本鲭产卵群体样品的生物学及繁殖力测定数据,对其群体结构、性腺指数GSI和繁殖力特征进行了研究。结果显示,目前东海中部日本鲭产卵群体年龄结构由1–5龄组成,以2–4龄占优势。日本鲭的个体绝对繁殖力为24770–734684粒,平均为(145575±10067)粒;纯体重相对繁殖力为175–1404 grain/g,平均为(524±24)grain/g;叉长相对繁殖力为102–2070 grain/mm,平均为(483±29)grain/mm。ANOVA分析结果显示,不同叉长组间的性腺指数GSI(F=2.34,P0.05)、绝对繁殖力(F=8.57,P0.01)和叉长相对繁殖力(F=5.59,P0.05)均有显著性差异,但体重相对繁殖力差异不明显(F=2.03,P0.05)。多元逐步线性回归和非线性回归分析显示,绝对繁殖力与体高、肝重关系密切。为了应对高强度的捕捞压力,日本鲭主要采用降低性成熟年龄,减小最小性成熟叉长和卵径、增加繁殖力等策略来维持种群的延续。  相似文献
9.
Oogenesis in the common Japanese conger Conger myriaster   总被引:1,自引:0,他引:1  
TOMOKO  UTOH  NORIYUKI  HORIE  AKIHIRO  OKAMURA  YOSHIAKI  YAMADA  SATORU  TANAKA  NAOMI  MIKAWA  ATSUSHI  AKAZAWA  HIDEO P  OKA 《Fisheries Science》2003,69(1):181-188
ABSTRACT:    We investigated the process and characteristics of oogenesis in the common Japanese conger Conger myriaster . Young fish caught in November 1996 were reared for use in this experiment. Fish were sampled monthly from December 1997 to August 1998. Some were injected with human chorionic gonadotropin to stimulate ovarian maturation from May to August 1998. Oocytes from the chromatin nucleolus stage to the secondary yolk globule stage were obtained from non-hormone-treated fish; those of more advanced stages were obtained from hormone-treated ones. We divided oocyte development into eight stages from the chromatin nucleolus stage to the maturation stage. The yolk vesicle stage was not separated because yolk vesicles began to appear just after appearance of yolk globules. Oocyte, oil droplet, yolk globule and nucleus diameters all increased concomitant with oocyte development. Oil droplet and yolk globule diameters increased remarkably at the maturation stage. However, zona radiata thickness peaked at the secondary yolk globule stage, decreasing gradually thereafter. Increased gonadosomatic index was related to oocyte development as found in European and Japanese eels receiving hormone treatment to mature. The present study is the first report describing oogenesis characteristics in congrid eels. It indicates that oogenesis is almost identical to that of other anguillid eels.  相似文献
10.
To evaluate the effect of anthropogenic pollution on fish reproduction in Bizerta lagoon, one of the largest Tunisian lagoons subjected to various anthropogenic and industrial pressures, the gonadosomatic index (GSI) and gonad histology of mature black goby (Gobius niger) were studied. Fish were collected during the breeding seasons from six stations differently impacted and in one reference station located at the seaward entrance of Ghar el Melh (GH) lagoon. In both sexes, we detected the presence of an overall weaker GSI in Bizerta lagoon than in control fish. These GSI alterations were accompanied by histopathological changes. In females, no significant differences in oocyte size were found across all the sample sites. However, a higher incidence of oocyte lesions (atretic oocytes, cytoplasmic retraction and karyoplasmic cluping) was found in stations located near agricultural activity zones. Histological observation of the testes revealed, as well, abnormalities in Bizerta lagoon fish: germ cells syncytium, vacuolated germ cells, melano-macrophage center and increase of gaps in the interstitium between lobules were detected with a high prevalence in stations influenced by industrial and/or urban activities. In addition, association between gonad fish histopathology and the presence of organic pollutants (DTT, PAHs and organotins) in sediment was noted. These results suggest that the chemical pollution in this lagoon may have adversely affected the gonad development of fish. In conclusion, this study is the first histological evidence of reproduction disturbance related to pollution pressure in a fish species inhabiting Bizerta lagoon. The high levels of gonad histopathology recorded raise concerns about the long-term health of fish populations in this lagoon.  相似文献
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