Role of photoperiod and melatonin in the regulation of ovarian functions in Indian carp <Emphasis Type="Italic">Catla catla</Emphasis>: basic information for future application

The major carp Catla catla is a popular freshwater edible fish and an extensively cultured species in India. However, basic information on the physiology of reproduction is lacking in this species. By virtue of its surface feeding habit, it maintains close contact with environmental light, and is a species of choice for the study of temporal organization of reproduction under natural and experimental conditions for understanding environmental and/or endocrine mechanisms that control the annual reproductive cycle. The present review covers information gathered in recent years to emphasize the temporal pattern of reproductive events and the importance of photoperiod and melatonin, a hormone of the pineal gland that links the environment with the endocrine system in the regulation of reproduction. Finally, the outcome of the research is discussed in terms of its direct and indirect applications to aquaculture of this species with a view to manipulate its breeding at a desired time of the year to meet market demand.     

黄海高眼鲽卵巢发育特征及卵径分布

本研究通过组织学观察,描述了黄海高眼鲽(Cleisthenes herzensteini)卵母细胞发育特征及其退化过程。高眼鲽卵母细胞发育分为5个时相:第1时相为卵原细胞,细胞体积小,细胞质少,细胞核明显;第2时相卵母细胞细胞核附近出现卵黄核;第3时相由胞质外缘向内层逐渐产生液泡并生成卵黄颗粒,出现双层滤泡膜;第4时相卵母细胞内充满卵黄,细胞核向动物极移动,放射膜增厚;第5时相细胞核溶解,卵母细胞从滤泡膜中释放出来并发生水合作用;产卵期过后,卵巢发生退化,卵黄颗粒逐渐被吞噬,放射膜溶解断裂。通过比较卵巢中各时相卵母细胞组成比例,表明卵母细胞发育具有非同步性。Ⅳ、Ⅴ、Ⅵ-Ⅳ'期卵巢内卵径(长径)呈单峰分布,优势粒径组分别为0.45~0.55 mm、0.60~0.65 mm和0.40~0.50 mm;Ⅴ'期卵巢,卵径分布呈双峰型,峰值分别为0.50~0.55 mm和0.90~0.95 mm,水合卵母细胞与卵径较小的小生长期卵母细胞比例增大,呈现出明显的双峰分批产卵型特征。     

绵羊卵巢卵泡颗粒细胞体外培养中促卵泡素和胰岛素浓度优化研究

为了进一步探讨在无血清体外培养条件下,促卵泡素(FSH)和胰岛素对绵羊卵巢颗粒细胞的影响,以优化颗粒细胞体外培养体系。试验设计6个FSH浓度梯度和3个胰岛素浓度梯度。体外培养7d后,检测培养体系中颗粒细胞数和雌激素浓度。与对照组相比,培养液中添加FSH与胰岛素可显著提高颗粒细胞的增殖和雌激素的分泌(P<0.01);且随着FSH浓度的增加,颗粒细胞数和雌激素分泌量显著增加,当FSH浓度为5.0μg·L-1时,雌激素分泌量最高;随着胰岛素浓度增加,颗粒细胞数和雌激素分泌量显著增加,当胰岛素浓度为10μg·L-1时,颗粒细胞数和雌激素分泌量最高。     

Imidazole derivative KK-42 reduces ecdysteroid titers and interferes with reproductive processes in adult females of Tenebrio molitor

KK-42, an imidazole derivative considered as potent inhibitor of ecdysteroid biosynthesis, was tested on adult females of Tenebrio molitor. The compound was applied topically (0.1, 1, 5, and 10 μg/insect) on 0- or 2-day-old adult females or added to the culture medium (1 and 10 μM) of ovaries. To test the effect of KK-42 on the reproduction capacity, ovaries were explanted from 2- and 4-day-old females corresponding, respectively, to follicles at the beginning and the end of vitellogenesis. KK-42 treatment reduced the fecundity and the longevity of females, and in addition, it delayed oviposition and affected growth and development of oocytes as evidenced by measurements of the ovarian weight, the number of oocytes per ovaries, and the size of the basal follicle. Hence, the effects were stronger in newly emerged females compared to 2-day-old females. Interestingly, RH-0345, an ecdysteroid agonist, could partly restore the effects on reproductive events induced by KK-42. In a second series of experiments using an enzyme immunoassay to measure ecdysteroid titers, KK-42 reduced the amounts of ecdysteroids in ovaries after application on newly emerged adult females. In 2-day-old females, it caused a significant effect with the highest doses. In addition, the compound significantly reduced the amounts of ecdysteroid released into the culture medium by ovaries explanted from 2- or 4-day-old females. The results are discussed in relation to the mode of action of KK-42 on reproduction.     

上海地区栽培的欧洲甜樱桃花器发育的观察

 为了探讨上海地区甜樱桃结实不良的原因，以5年生欧洲甜樱桃(Prunus avium L．)为试验 材料，就其花器发育状况进行了探讨。结果表明，上海地区生长的甜樱桃花芽形成良好，雌蕊、雄蕊外观形态无异常。花粉粒形态正常，发芽率达50％左右，但有98．2％的子房发育不正常，其中无胚珠分化的子房占26．3％ ，有胚珠而无胚囊分化的子房占71．9％ 。胚珠、胚囊发育不良是上海甜樱桃不能正常结实的主要原因。     

发情期蓝狐卵泡发育的显微结构观察(英文)

[目的]对发情期蓝狐卵巢的组织结构和卵泡发育过程的变化进行研究。[方法]采集10只发情期蓝狐的左侧卵巢共计10枚,利用光学显微镜对卵巢的组织结构和卵泡的发育过程进行观察,同时利用目镜测微尺和显微照相技术分别对30个原始卵泡、30个初级卵泡、15个生长卵泡、15个囊状卵泡、15个成熟卵泡及各级卵泡中的卵母细胞进行测量和拍照。[结果]蓝狐卵巢由生殖上皮、白膜、皮质和髓质构成。皮质内分布着大量的间质细胞及不同发育阶段的卵泡,位于卵巢的外周;髓质位于皮质下层,分布着较多的血管。卵泡发育过程中,各级卵泡和卵母细胞的直径差异较大(卵泡为45.45~974.55μm,卵母细胞为30.23~147.27μm),在初级卵泡阶段出现透明带物质。卵泡闭锁发生于卵泡生长的各个时期,主要表现为卵母细胞的皱缩,细胞核固缩;颗粒细胞松散、退化。[结论]为揭示雌性蓝狐的生殖机理提供了组织学依据。     

Effects of paraquat and glyphosate on steroidogenesis in gonads of the frog Rana esculenta in vitro

Herbicides are toxic for amphibians, influencing various developmental stages. In particular, paraquat and glyphosate have teratogenic effects on tadpole development, though little information is available on how they affect reproduction in amphibians. In the present work, ovarian tissue and testis of the water frog Rana esculenta were incubated in vitro in presence of different concentrations of the two herbicides. 17β-estradiol and testosterone levels were measured in the incubation medium by radioimmunoassay. The data showed that paraquat inhibited testosterone and 17β-estradiol production, with the lowest-observed-effect concentration (LOEC) of 10⁻⁴ M, while paraquat inhibition of steroidogenesis in amphibian gonads was reversed by the presence of epigallocatechin gallate in the culture medium. These result indicates that paraquat acts on gonadal steridogenesis through a mechanism involving reactive oxygen species. Glyphosate showed no effect on gonadal steroidogenesis. These results suggest that paraquat may interfere in amphibian reproductive processes.     

腹腔镜检查山羊超排反应准确性的手术评价

用手术法评价了192例超排山羊卵巢反应的腹腔镜检查结果。结果表明用腹腔镜检查计数超排羊的黄体数时,其准确性随黄体数和未排卵大卵泡数(直径>5 mm)的增多而降低;计数大卵泡时,其准确性随大卵泡数的增多而降低,但黄体的多少对大卵泡计数准确性无影响;超排羊卵巢体积较大时黄体及大卵泡计数的准确性降低;被检羊膘情较好且检查前饥饿不足时,对黄体及大卵泡计数的准确性有不利影响。