黄海南部小黄鱼Pseudosciaena plyactis(Bleeker)渔获群体结构与繁殖特征的初步研究   总被引：6，自引：1，他引：6  

任一平  高天翔  刘群  薛莹 《海洋湖沼通报》2001,(1):41-46

本文对黄河南部小黄鱼繁殖群体进行了常规生物学测定。研究分析了体长组成和体重组成、体长和体重关系、性比的变化、怀卵量及性腺的发育情况。总样品中的性比组成为雌：雄＝1：2．7，且雄鱼比例逐月上升；测算其怀卵量在2686－34704粒之间，平均怀卵量为9518粒；性成熟系数3月中旬为116‰，5月下旬只有33‰；绝对繁殖力（F）与体重（W）的关系式为：F＝549．37W－4861．79（R＝0．917）。  相似文献   

Reproductive cycle and minimal length at sexual maturity of Engraulis encrasicolus (L.) in the Zrmanja River estuary (Adriatic Sea, Croatia)     

G. Sinov i&#x;  B. Zorica 《Estuarine, Coastal and Shelf Science》2006,69(3-4):439

The reproductive cycle of anchovy, Engraulis encrasicolus (L.), was studied from monthly random samples of purse seine catches. A total of 1477 anchovy specimens were collected from January to December 2003 in the Zrmanja River estuary (Novigrad Sea). The analysis was based on the temporal evolution of gonadosomatic index, mass and stage of gonads. The total length of anchovy ranged from 4.5 to 14.5 cm and mass from 0.56 to 19.80 g. Sex ratio was slightly different from 1:1; the females were insignificantly predominated (♂/♀ = 0.99). The period of reproductive activity was from April to September coinciding with the most developed stages of gonads as well as with the highest gonad weights, and gonadosomatic indices. To estimate the length at maturity, a sub sample of 454 anchovy was taken from May to July (peak of anchovy spawning period). The length at which 50% of anchovy were mature (L₅₀) was calculated to be 8.2 cm. The length–weight relationship of anchovy was described by the expression: W = 3.51 × 10⁻³ L_T^3.211 (r² = 0.998). The relationships between total length–standard length and total length–fork length are L_T = 1.1405L_S + 0.2420 and L_T = 1.0425 L_F + 0.3944, respectively.  相似文献   

敏捷瘦体虫(Urosomoida agiliformis FOISSNER,1982)无性生殖期间的形态发生研究(原生动物,纤毛虫)     

王梅  宋微波 《中国海洋大学学报(自然科学版)》1996,(2)

敏捷瘦体虫（UrosomoidaagiliformisFOISSNER，1982）为小型腹毛目纤毛虫。利用银染法对该种二分裂期间的形态发生学进行初步研究，指出该虫形态发生的主要过程为：1．伴随大核改组带的出现，口原基发生于老口围带的下方，后演化为后仔虫的口围带。在前仔虫，老口围带及口侧膜完全保留并被继承；2．体棘毛场首先出现后一组棘毛原基，后形成前棘毛场，随后各自独立演化成前后仔虫的8：3／4：2／3模式的额-腹-横棘毛；3．在背触毛中，分别于前、后仔虫的中部产生前、后3列新原基，每列原基向其两端伸展替代老背触毛列，成为前、后仔虫相应的3列新触毛；接着，在右缘棘毛原基右前端发生前、后第4列背触毛。  相似文献   

Reproductive biology of catsharks (Chondrichthyes: Scyliorhinidae) off the west coast of southern Africa   总被引：1，自引：0，他引：1  

Ebert  David A.; Compagno  Leonard J.V.; Cowley  Paul D. 《ICES Journal of Marine Science》2006,63(6):1053-1065

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Age, growth, and reproduction of the roughskin skate, Dipturus trachyderma, from the southeastern Pacific     

Licandeo  Roberto; Cerna  Francisco; Cespedes  Renato 《ICES Journal of Marine Science》2007,64(1):141-148

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Observations on the reproductive cycle of the black scabbardfish (Aphanopus carbo Lowe, 1839) in the NE Atlantic     

Figueiredo  I; Bordalo-Machado  P; Reis  S; Sena-Carvalho  D; Blasdale  T; Newton  A; Gordo  L.S 《ICES Journal of Marine Science》2003,60(4):774-779

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Similar reproductive cycles and life-history traits in congeneric limid bivalves with different modes of nutrition     

Johanna Järnegren  Hans T. Rapp  & Craig M. Young 《Marine Ecology》2007,28(1):183-192

We have studied two congeneric limid bivalves, Acesta species novum and Acesta excavata (Bivalvia: Limidae), that live in similar physical conditions but use different food sources. Acesta sp. nov. live on the giant siboglinid tubeworm Lamellibrachia luymesi at cold seeps and feed on their eggs, a continuous food source that ultimately is derived from chemosynthesis, whereas A. excavata relies on planktonic food of photosynthetic origin, which varies seasonally. We hypothesized that these two species might show differences in the periodicity of reproduction; specifically, we predicted that A. sp. nov. would breed continuously and that A. excavata would demonstrate an annual reproductive cycle. Our hypothesis was refuted, as both species have a semi‐continuous reproductive cycle. Food quality, quantity or seasonality had no clear effect. Reproductive adults are functionally gonochoristic. Females broadcast buoyant eggs with an average size of 179 μm in A. sp. nov. and 160 μm in A. excavata. Both the size of the larval shell and the size of the spawned eggs are suggestive of pelagic lecithotrophic development. Both species also appear to be protandric hermaphrodites, changing from male to female at approximately 77 and 90 mm shell height, respectively, although not all individuals change sex. In the material investigated in this study there was a biased sex ratio favouring males.  相似文献   

Aspects of the Reproductive Activity of Penaeus semisulcatus de Haan along the Southeastern Coast of the Mediterranean     

A. Shlagman    CH. Lewinsohn  M. Tom 《Marine Ecology》1986,7(1):15-22

Abstract. Reproductive parameters of the females of Penaeus semisulcatus regarding the process of ovary maturation, the degree of synchronization of the ova maturation stage within an ovary, the correlation between female length and both maturity and fecundity, as well as the relationship between moulting, copulation and ovarian maturity stage were investigated.
The seasonal and spatial pattern of the reproduction of the female population of P. semisulcatus along the southeastern coast of the Mediterranean was determined.
Average ova diameter, morphological appearance of the ova, presence of sperm, characteristics of the spermatophore, and hardness of the cuticle were used in order to study the above parameters.  相似文献   

养殖比目鱼生殖及其调控机理研究进展     

温海深  宋海霞 《中国海洋大学学报(自然科学版)》2004,34(2):182-188

综述了养殖比目鱼生殖及其调控机理研究的最新进展,包括雌鱼卵巢发育及其外源激素和光温调控,雄鱼精巢发育及其外源激素和光温调控,性别分化的温度决定机制,早期性别鉴定方法等.旨在为我国比目鱼的养殖和研究提供科学依据.  相似文献   

Sexual maturity in the velvet swimming crab Necora puber (Brachyura, Portunidae): morphometric and reproductive analyses     

Gonzalez-Gurriaran  Eduardo; Freire  Juan 《ICES Journal of Marine Science》1994,51(2):133-145

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