福建北部海域海地瓜（Acaudina molpadioides）的性腺发育研究

海地瓜（Acaudina molpadioides）是一种低值海参,本研究运用组织学和形态学方法对福建北部海域海地瓜的性腺发育特征及其周年变化进行了研究,并进一步探究了性别比、生殖周期、精卵排放类型、繁殖季节等繁殖生物学相关内容。结果表明,雌、雄海地瓜的性腺发育均可划分为休止期 (I)、发育早期 (II)、增长期 (III)、成熟期 (IV)、部分排放期 (V) 和排空期 (VI),雌、雄性腺发育程度基本同步。海地瓜性腺发育有明显的周年变化规律:大多数海地瓜在5月性成熟后开始陆续排放配子,配子排放过程中伴随着生殖管的自体破坏然后重生,即性腺开始新一轮发育,新的生殖细胞在11月开始生成并逐步发育直至翌年5月成熟。海地瓜性别比接近1∶1,生殖周期为1年,繁殖期为5?8月（夏季）,属于多次排精卵类型。     

水温对文昌鱼生殖活动的影响及其内分泌机制

采用慢性实验方法,研究在不同水温条件下饲养性腺发生前的文昌鱼(Branchiostoma belcheri)对其性腺分化和发育的影响。另外,在繁殖季节研究在低温16℃、中温22℃和高温28℃下饲养性成熟的文昌鱼对其产卵和排精的影响。同时,采用免疫组织化学方法对几种生殖相关激素在不同发育期文昌鱼的生殖调控轴(脑-哈氏窝-性腺)中的分布进行免疫识别,并用磁酶免定量测定方法检测睾酮和17 β-雌二醇在文昌鱼性腺中的含量,以分析和探讨水温影响文昌鱼生殖活动的内分泌机制。结果表明:低温有利于文昌鱼性腺向雌性分化,雌雄比例为4.2:1,中温和高温组则不受影响,雌雄数量大致相等。高水温则有利于文昌鱼的精巢发育和生精活动。28℃海水适于文昌鱼的产卵和排精。根据免疫组织化学和磁酶免定量测定的结果分析提示,温度影响文昌鱼性别分化和发育以及繁殖活动的内分泌机制是:首先水温经皮肤或哈氏窝化学感受器,刺激神经系统(脑泡)释放GnRH。然后GnRH促进哈氏窝分泌LH,从而可能刺激性腺产生和分泌性类固醇激素,始动文昌鱼性腺的发育至成熟及其生殖活动。此外,脑中芳香化酶可能介导文昌鱼性别分化。     

Reproductive Cycle of the Caribbean Feather Star Nemaster rubiginosa (Echinodermata: Crinoidea)

Abstract. The reproductive cycle of the comatulid crinoid Nemaster rubiginosa from Discovery Bay, Jamaica is described histologically. The cycle is annual and may be divided into (1) a "resting" phase (summer) in which most adults possess immature, unsexable gonads, (2) a recovery phase (early fall) marked by the re-initiation of gametogenesis and rapid gonadal growth, (3) a breeding phase (late fall and winter) during which the gonads are mature and repeated spawning likely takes place, and (4) a post-spawning phase (spring) during which relict gametes are removed from the shrinking gonads. Although unsexable individuals predominate during the "resting" phase, a small proportion of the adult population is unsexable at all times of the year. The reproductive condition of animals in the same month in two successive years was very similar, suggesting that the timing of reproduction is quite predictable from year to year. The re-initiation of gametogenesis in the early fall is correlated with both rising sea temperature and shortening daylength, and the October to March breeding season corresponds to the period of short daylengths at the study site. The well-defined and synchronized annual reproductive cycle of Nemaster rubiginosa contrasts with the more prolonged and variable reproductive cycles reported for other tropical crinoids and points to a diversity of breeding patterns among tropical crinoids.     

三倍体牡蛎在繁殖季节的生长研究

研究了在繁殖季节内三倍体太平洋牡蛎的生长情况。结果表明 ,三倍体牡蛎比二倍体对照组具有明显的生长优势。在整个繁殖期间 ,三倍体的体重明显高于二倍体。三倍体的生长速度较均匀 ,而二倍体变化较大。在集中排放前体重增长较快 ,集中排放后体重增长明显减慢。三倍体的平均体重在排放前比二倍体高 17%左右 ,在排放后则高达 30 %以上。集中排放前 ,二倍体的软体重增长很快并超过了三倍体 ,其出肉率比三倍体高 2 6 .4 8%。排放后二倍体的软体重明显降低 (降低 4 8% ) ,出肉率降低 4 0 .0 % ,而三倍体变化不明显 ,出肉率仅降低 5 .79%。繁殖高峰后三倍体的软体重比二倍体高 4 1.2 2 %。三倍体牡蛎较低但稳定的出肉率表明三倍体太平洋牡蛎具有高度的不育性 ,但三倍体的不育性并不是引起三倍体生长优势的主要原因     

Using oocyte size to assess seasonal ovarian development in Solea solea (L.)

Maximum oocyte size was used to assess seasonal ovarian development in sole. Fish age, especially the adolescent period, appeared to affect the start of vitellogenin-dependent oocyte development in the annual reproductive cycle and the subsequent oocyte growth rate. The majority of oocyte growth occurred between September and March. Several other aspects of ovarian development were also age-dependent, including the increase in ovary condition factor (ovary weight/fish length³) and the size of oocytes commencing nuclear migration. Evidence is presented that in the recruiting year class of sole abortive maturation occurs where oocytes develop yolk but spawning does not take place. The implications of this study on the estimation of female spawning stock biomass are discussed.     

Changes of melatonin and its receptors in synchronizing turbot (Scophthalmus maximus) seasonal reproduction and maturation rhythm

In most fish, reproduction is seasonal or periodic under the suitable conditions. In turbot(Scophthalmus maximus) farms, one of the most economically important marine flatfish species, changes in daylength could cause changes in the spawning time. In this study, to characterize the regulation of reproductive physiology following light signals, three melatonin receptors(Mtnr) investigated in turbot were named sm Mtnr1, sm Mtnr2,and sm Mtnr1 c. Distinct expression profiles demonstrated that Mtnr m...     

Influence of age,size and condition factor on lipid concentration in the snapper Chrysophrys auratus

Survival, growth rates and functionality of larvae have been hypothesised to correlate with higher lipid provisioning in older teleosts. To test the lipid provisioning part of this hypothesis, we investigated the total and relative (mg/g) lipid (triglyceride) concentration in both the source (liver) and sink (gonad) lipidation organs of female snapper Chrysophrys auratus across age, size and condition factor throughout its spawning season. Age, size and condition factor had little discernible effect on the total or relative lipid concentration in either liver or gonadal tissue. Therefore, if oocyte quality (based on triglyceride concentration) is comparable across a population, research on the relationship between lipidomics and reproductive success needs to move beyond highlighting correlations to elucidating causation by focusing on the biochemical mechanisms of egg quality and larval survival, identifying maternal parameters associated with consistent lipid provisioning, and partitioning of phenotypic and genotypic maternal influences.     

Linking sardine spawning dynamics to environmental variability

The present paper investigates the effect of environmental variability on the spawning dynamics of sardine, Sardina pilchardus, in the Eastern Mediterranean. To do so, variability in four different reproductive traits, i.e. reproductive activity, incidence of recent spawning, prevalence of early ovarian atresia and relative batch fecundity was tested along a gradient of habitat conditions like water temperature, chlorophyll a (Chl a) concentration and an index of zooplankton production. Apart from atretic prevalence all remaining traits were significantly and positively correlated with Chl a concentration which indicates that sardine in the E. Mediterranean tends to enhance egg production under conditions of increased primary productivity. On the other hand, prevalence of atresia together with spawning incidence were positively affected by water temperature whilst the only factor that correlated significantly with the index of zooplankton production was relative fecundity. These findings were interpreted as an indication of direct energy flow from phytoplankton filter-feeding to gonadal development and egg production, implying that besides capitalized energy sardine also uses current income for supporting reproduction.     

厦门皱瘤海鞘性腺发育的组织学研究

皱瘤海鞘雌性同体。性腺组织学观察结果表明，在厦门皱瘤海鞘卵巢和精巢发育和成熟可分为５人时期，在同一人体中，卵巢和精巢的发育不同步，因而不发生自体受精，另外，根据性腺发育的季节性观察，皱瘤海鞘常年都可繁殖，但生殖旺季在６月。     

青蛤的繁殖周期

青蛤Cyclina sinensis采自福建漳浦佛昙湾。依据青蛤生殖细胞的发育规律,把生殖腺发育过程分为五期:增殖期、生长期、成熟期、排放期和休止期。青蛤怀卵量与个体体积存在线性关系:F=0.6046 0.1266V。根据青蛤肥满度、生殖腺指数和性成熟率等指标的周年变化规律,并结合性腺组织切片观察结果,认为青蛤繁殖期在9—12月,其中9月下旬至10月中旬为繁殖盛期。文中还就水温与青蛤繁殖期的关系进行了讨论。     

Gonadal cycle of the dwarf oyster Ostreola stentina from the south of the Gulf of Hammamet on the eastern coast of Tunisia

The reproductive cycle of the dwarf oyster Ostreola stentina (Payraudeau 1826) at Monastir in the south of the Gulf of Hammamet on the east coast of Tunisia was studied using condition indices and histological techniques. The species was shown to be a protandric hermaphrodite. Whereas males dominated the small shell length categories (12.45–34.99 mm), females (21.00–47.16 mm) and hermaphroditic individuals (30.00–57.95 mm) become more predominant with increasing size, suggesting that individuals may undergo protandric development. The overall male to female ratio was 1.0:1.7. Gametogenic development begins in February–March for females and in September for males, and spawning occurs during April and July for females and December and July for males. There was a clear relationship between the gonadal condition index and gametogenic stage for both sexes. Values increased from zero in their early stage of development and peaked during ripe and spawning stages, before decreasing in the spent stage. However, the meat condition index did not show any statistical differences between gametogenic stages.     

Reproductive biology of blood cockle <Emphasis Type="Italic">Anadara granosa</Emphasis> (Bivalvia: Arcidae) in the northern region of the Strait of Malacca

A study on the reproductive cycle of the blood cockle Anadara granosa (Bivalvia: Arcidae) was conducted at three different areas in the northern region of the Strait of Malacca. A total of 1,920 samples of adult A. granosa (38–71 mm length) were collected from June 2009 until September 2010. Qualitative techniques (gonadal microscopic fresh smear test and histology analysis) as well as quantitative techniques (analysis of condition index and gonadal index) were used to predict monthly gonadal development stages of A. granosa. The gonadal index of A. granosa from Banda Aceh (Indonesia) (r = 0.469, P > 0.05) and Pulau Pinang (Malaysia) (r = 0.123, P > 0.05) did not show any correlation to their condition index, whereas the gonadal index of A. granosa from Lhokseumawe (Indonesia) (r = 0.609, P < 0.05) showed moderate positive correlation to the condition index. During the 16 month sampling period, four reproductive cycles were observed: each from three to six months. The process of releasing gametes is termed dribble spawning, and is the same in all populations. The principle component analysis (PCA) indicated that A. granosa reproduction was affected by interaction between internal physiological factors and indigenous environmental factors. In all sampling areas, phytoplankton density played a key role in the reproductive cycle in A. granosa. Information on the reproductive biology of this species is essential for species management and to improve the sustainability practices of the fisheries industry. These findings will provide basic information on the biology of the blood cockle A. granosa for stock management in the region.     

Aspects of reproduction of the brown mussel Perna perna at the Iture rocky beach near Cape Coast,Ghana

Aspects of the reproductive biology of the brown mussel Perna perna at the Iture rocky beach near Cape Coast, Ghana, were studied from September 2014 to August 2015. The current study was aimed at providing information useful for managing the mussel fishery in this locality and also that would form the basis for designing appropriate culture methods for the species. Microscopic examination of fresh smears of gonadal material, as well as histological preparations of the gonad, were used to study the sexuality and breeding pattern of the species. Monthly gonadal and condition indices were also determined. Perna perna exhibited gonochoristic sexuality with a sex ratio of approximately 1:1 throughout the study period. Sexes were identifiable at shell lengths of 15.0–19.9 mm. Five stages of gonadal development were identified in both sexes. Gametogenic activity was continuous throughout the year, with two major spawning activities, from April to June and from August to December. These periods coincided with the major and minor rainy seasons, respectively, as well as the major upwelling period in August. Condition indices suggest that the mussels were in better condition for harvesting in March and August prior to the major spawning events.     

Geographical implications of seasonal reproduction in the bat star Asterina stellifera

The reproductive cycle and environmental cues that regulate gonad production in Asterina stellifera were studied from April 2009 to April 2011 in a rocky subtidal habitat at the southernmost limit of its distribution (Mar del Plata, Argentina). The geographic variation in reproductive traits between latitudinal range limits was analyzed. The gonadal and pyloric caeca weight varied with sea star size and time in both sexes. Despite a previous study which suggested the absence of recruitment in a 4 year period, our data of the same period demonstrated that spawning happens from early spring to early summer. The gonad and pyloric caeca weight did not show an inverse relationship, this suggested that there is no dependence on energy transfer between the organs and that the bat star presented a good nutritional state. Seawater temperature appears to be the variable explaining gonad proliferation at the range limits of A. stellifera distribution. Furthermore, differences in sex ratio, oocyte production, oogenesis duration and capability of energy transformation into ova were found between range limits.     

南海鸢乌贼中型群雄性个体肌肉和性腺组织能量积累及其分配

利用组织能量密度测定技术和残差指标分析方法, 分析了南海鸢乌贼中型群雄性个体肌肉组织和性腺组织的能量积累及其分配变化过程。结果显示, 胴体、尾鳍、足腕、精荚复合体、精巢等组织的能量密度值分别为21.16±1.44、21.98±1.51、21.44±1.50、20.83±1.70和21.41±1.70kJ?g ^-1。胴体和精荚复合体两组织的能量密度在不同性腺成熟度之间均存在显著性差异, 而尾鳍、足腕、精巢等3种组织的能量密度则在不同性腺成熟度之间均没有统计学差异。个体总能量积累为299.31±90.81kJ; 随着个体生长, 总能量积累呈现增加的趋势。胴体、足腕和尾鳍等肌肉组织的能量占比为95.31%~98.04%, 随着性腺发育呈现降低的趋势; 精巢和精荚复合体等性腺组织的能量总投入占比为2.63%~5.33%, 随着性腺发育呈增加的趋势, 并在Ⅴ期达到最大值。同时, 残差指标分析显示, 胴体、尾鳍、足腕等肌肉组织能量积累-胴长残差与性腺组织能量积累-胴长残差呈显著的正相关关系, 表明个体性腺发育过程中肌肉组织能量没有转化用于性腺组织的生长发育, 其生殖能量投入倾向于外源性投入。初步掌握了南海鸢乌贼中型群雄性个体肌肉和性腺组织能量的积累变化过程, 为深入了解它们的繁殖策略和为可持续开发利用该种类资源提供了科学基础。     

大竹蛏的繁殖生物学

2005年1月至2007年12月,采用组织学和实验生态学方法对大竹蛏(Solen grandis Dunker)的性腺发育、生殖周期、肥满度、胚胎发育、幼虫发育及变态等进行了研究.结果表明,大竹蛏性腺发育过程分为增殖期、生长期、成熟期、排放期、休止期5个阶段;在浙南沿海大竹蛏繁殖期为4月下旬至5月中旬(水温21～24℃);肥满度最高出现在5月份,为31.2%;最低出现在2月份,为21.2%.大竹蛏卵径为85～95 μm;受精卵在水温22℃,经20～24 h孵化成D形幼虫;初孵D形幼虫平均大小为125 μm,浮游幼虫经5～6 d培养进入附着变态期,壳长为250 μm,发育变态为稚贝.     

尖紫蛤生殖周期的研究

根据尖紫蛤Ｈｉａｔｕｌａａｃｕｔａ发育程度，将生殖腺发育过程分为增殖期、生长期、成熟期、排放期和休止期五个时期。尖紫蛤生殖期在福建省为９—１１月，生殖盛期在１０月．温度是影响性腺发育的主要因素。绝大多数个体为雌、雄异体。雌、雄同体的同一滤泡中，雌、雄生殖细胞分区域分布。较晚期的卵母细胞和成熟卵子的核仁变成双质核仁，组织化学实验结果表明，双质核仁染色深浅的两部分，是由于这两部分蛋白质含量不同的缘故。     

扁玉螺的生殖腺组织学和生殖周期

采用组织切片和HE染色法,对烟台沿海扁玉螺的生殖腺发育过程进行了观察.根据性腺发育的组织学特征,将扁玉螺生殖腺发育过程分为增殖期、生长期、成熟期、排放期和休止期5个时期;扁玉螺在烟台沿海每年一个生殖周期,繁殖季节为5月上旬至8月中旬,繁殖盛期为6月上旬至7月下旬.上述研究结果探明了扁玉螺的生殖腺发育规律,丰富了扁玉螺的繁殖生物学资料,对开发利用扁玉螺有着积极的意义.     

Modeling fish growth and reproduction in the context of the Dynamic Energy Budget theory to predict environmental impact on anchovy spawning duration

Spawning location and timing are critical for understanding fish larval survival. The impact of a changing environment on spawning patterns is, however, poorly understood. A novel approach is to consider the impact of the environment on individual life histories and subsequent spawnings. In the present work, we extend the Dynamic Energy Budget (DEB) theory to investigate how environment variability impacts the spawning timing and duration of a multiple-batch spawning species. The model is successfully applied to reproduce the growth and reproduction of anchovy (Engraulis encrasicolus) in the Bay of Biscay. The model captures realistically the start and ending of the spawning season, including the timing of the spawning events, and the change in egg number per batch. Using a realistic seasonal forcing of temperature and food availability derived from a bio-physical model, our simulation results show that two thirds of the total spawned mass already accumulates before the start of the spawning season and that the condition factor increases with body length. These simulation results are in accordance with previous estimations and observations on growth and reproduction of anchovy. Furthermore, we show how individuals of equal length can differ in reproductive performance according to the environmental conditions they encounter prior to the spawning season. Hatch date turns out to be key for fecundity at age-1 as it partly controls the ability to build up reserves allocated to reproduction. We suggest the model can be used to realistically predict spawning in spatially and temporally varying environments and provide initial conditions for bio-physical models used to predict larval survival.     

大黄鱼性早熟的机制:精巢中间质细胞和足细胞的显微与亚显微结构

本文应用组织学和电镜技术对性早熟与未成熟雄性大黄鱼精巢中间质细胞和足细胞进行显微与亚显微结构的研究。结果表明，这两种细胞在精巢不同发育时期的精细结构出现明显的差异。早熟精巢间质细胞和足细胞胞质中滑面内质网池和管状线粒体都十分发达，而未成熟鱼则发育较差。我们认为雄性大黄鱼性腺早熟的原因可能与间质细胞和足细胞提早发育成熟有关。