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1.
四眼斑水龟雌性生殖器官组织结构的季节变化   总被引:3,自引:0,他引:3  
傅丽容  洪美玲  史海涛  张扬波  钟昌茂 《四川动物》2006,25(2):360-363,I0002
应用石蜡常规切片,HE染色,分别在3月(春季)、8月(夏季)、10月(秋季)、1月(冬季),对24只四眼斑水龟雌性生殖器官组织结构变化进行研究,结果表明:四眼斑水龟雌性生殖器官的形态和结构存在季节性的变化,8月卵泡开始发育,卵巢增重,子宫腺增多;10月卵巢增重达最大,卵泡发育成熟开始排卵,随后形成黄体,进入排卵期。翌年的1~3月卵巢重量减轻,输卵管管腔增大,腺体增多,子宫肌层不断增厚,进入产卵期。  相似文献   

2.
为探讨光周期对四眼斑水龟(Sacalia quadriocellata)繁殖的影响,于2008年10月至2009年9月对其进行光周期实验.将39只成体分成短光照组、长光照组和对照组,每个组别中样本量均为7♀、66.每月用超声波技术对雌性个体进行卵泡数量、大小的检测,并用X光投射法确定硬壳卵数;每半月对雄性进行录像观察.结果表明:三个实验组卵泡数量和卵泡大小表现出明显的周期性,原始卵泡从8月份开始生长发育,卵泡数量在11月份最多,尺寸在12月份也达到最大值;光周期对雌性卵泡数量和卵泡大小的发育有影响,短光照组检测到的总卵泡数高于长光照组和对照组,其中短光照组卵泡数与对照组卵泡数差异显著(P<0.05),长光照组卵泡尺寸相对于另外2个实验组显著变小(P<0.01);光周期对雌性产卵数和雄性发情强度无影响(P>0.05).光周期对四眼斑水龟雌雄个体性腺发育的作用不同,缩短光照对雌性繁殖有促进作用,延长光照对雄性发情强度在特定阶段具有一定促进作用.  相似文献   

3.
李闯  傅丽容  马凯  李敏  史海涛 《四川动物》2013,(5):713-716,721
2011年10月至2012年9月期间,于海南岛万泉河琼海段的沙洲岛开展外来物种红耳龟野外繁殖生态研究。通过笼捕等方法获得54个红耳龟样本,所有样本采用超声波技术检测其卵泡数量和大小。结果显示红耳龟的卵泡在9月开始生长发育,次年6月达到最大(16.6 mm±3.9 mm,n=39),随后逐渐减小,各月卵泡直径平均值大于9.0 mm(6.033.7 mm,n=426);卵泡数量于1月开始增加,3月份达到最多(45±4,n=4),随后逐渐减少。推测研究区域内的红耳龟年繁殖频次为2.48窝/年。  相似文献   

4.
四眼斑水龟血浆生殖激素季节性变化   总被引:1,自引:0,他引:1  
为了进一步探讨四眼斑水龟(Sacalia quadriocellata)的繁殖生理周期和生殖激素分泌特征,使用放射免疫分析测定法(RIA)分别测定了8月(夏季)、10月(秋季)、1月(冬季)、3月(春季)四眼斑水龟血浆中卵泡刺激素(FSH)、促黄体生成素(IJH)、睾酮(T)、雌二醇(E2)、孕酮(P)五种生殖激素的含量.结果显示,四眼斑水龟生殖激素分泌呈现较明显的周期性,激素水平与环境温度的变化有关;雄性T含量夏季开始升高,秋季达到高峰,与精子的发生和成熟同步;雌性T水平升高促进其接受雄性爬胯,且作为雌激素合成的前体物质,间接作用于雌激素的合成;排卵会出现LH峰,E2含量排卵前几个月开始增长,刺激肝生成卵黄;排卵期间P含量较高,可能在排卵过程中发挥作用.  相似文献   

5.
用光镜和电镜观察了中国大鲵卵泡闭锁过程和闭锁小体的显微和超微结构。结果显示 ,大鲵闭锁小体是卵泡细胞侵噬卵母细胞并增殖形成细胞团 ,膜细胞未参与。在大部分卵泡处于缓慢生长期时 ,未发现卵泡闭锁现象 ;在 5、 6月份 ,卵巢内大部分卵母细胞进入卵黄形成前期 ,部分卵泡闭锁 ,但闭锁小体细胞的类固醇激素分泌结构特征不明显 ;在 7、 8月份 ,大多数卵母细胞处于卵黄形成期 ,闭锁小体细胞具有管泡状嵴线粒体、丰富的滑面内质网和脂滴、发达的高尔基体等。这些细胞学特征表明闭锁小体可分泌类固醇激素 ,以调节正常卵子的成熟。在大鲵中观察到的闭锁小体属于排卵前黄体  相似文献   

6.
海南岛黎母山四眼斑水龟对春季生境的选择性   总被引:11,自引:1,他引:10  
2004年3—4月,在海南岛黎母山采用系统抽样法对四眼斑水龟春季生境选择进行了初步研究。在海拔170~1170m设196个研究样点,共1392个笼捕日。其中在海拔170~470m的26个布笼点共捕获四眼斑水龟36只,而在海拔470~1170m未捕获到四眼斑水龟。采用Kruskal Wallis检验,对海拔500m以下四眼斑水龟利用样地(n=26)和海拔500m以上的对照样地(n=26)的生态因子差异显著性进行检验。结果表明,两类样地的海拔、植被类型、植被盖度、落叶厚度、土壤类型、坡度、水面宽、水深、水面流速、基底类型、露石率、食物丰度、干扰距离13个生态因子差异均显著,仅石洞数目差异不显著。说明海拔500m以上和以下的环境差异较大。主成分分析结果表明,影响四眼斑水龟生境选择的主要生态因子依次为海拔、干扰距离、植被盖度、土壤类型、水深和落叶厚度。而植被类型、食物丰度、露石率、基底、石洞数目、坡度、水面宽和水面流速8个生态因子的影响不明显。保护好近河岸植被和提高当地群众对龟类的保护意识对四眼斑水龟的保护十分重要。  相似文献   

7.
乌梢蛇卵巢显微结构的年周期变化   总被引:1,自引:0,他引:1  
应用光学显微镜观察了乌梢蛇卵巢结构的年周期变化,并结合卵巢形态及卵巢系数的年周期变化探讨了其生殖规律.结果 表明,乌梢蛇的卵巢形态、卵巢系数及卵泡发育均具有较为明显的季节变化.据此认为,乌梢蛇在陕南地区的排卵时间在6月中下旬到7月上旬;乌梢蛇卵泡在不同发育阶段会产生闭锁卵泡或闭锁黄体,其意义可能在于使得体内合成的有限卵黄首先保证少量卵泡得到充分发育并排卵,最终达到延续种族的目的 .  相似文献   

8.
扬子鳄(Alligator sinensis)是中国特有的珍稀物种,该物种的生长、繁殖状况一直备受关注,分别在2014年3月(冬眠期)和6月(繁殖期)对17条成年雌性扬子鳄腹部应用VIVIDⅠ型彩色多普勒超声(B型超声)便携诊断仪进行检测,并对3月份卵巢卵泡大小用SPSS 19.0回归分析。扬子鳄心、肝、肠等内脏器官形态在B型超声诊断仪下清晰可见。冬眠期17条扬子鳄两侧卵巢中共检测到41枚卵泡,繁殖期共42枚。冬眠期卵泡处于低回声暗区或无回声暗区的未成熟状态,繁殖期多数卵泡的发育状态与3月相同,少数卵泡呈高回声暗区,此时已形成卵黄颗粒,也有呈高回声亮光区形成卵黄膜的卵泡。对3月份检测的17条扬子鳄具有卵泡的19个卵巢大小与卵泡大小进行回归分析,卵巢随卵泡发育而增大。本研究探讨了B超这种低损伤方法对扬子鳄检测的有效性,同时评估卵泡发育状况,提高繁殖鳄的筛选正确率。  相似文献   

9.
猪分离卵泡体外培养过程中Fas/FasL对颗粒细胞凋亡的作用   总被引:2,自引:0,他引:2  
从猪卵巢分离完整有腔卵泡,按质量分为3类:健康卵泡、早期闭锁卵泡和晚期闭锁卵泡。猪分离卵泡经眼观检查后再行石蜡切片和HE染色,形态学研究表明,眼观检查对于健康卵泡的判定准确率为92%。取健康卵泡按直径大小分为3组:直径>5 mm大卵泡组、3~5 mm中卵泡组和≤3 mm小卵泡组。卵泡培养8、16和24 h,以Annexin-V FITC/PI双染流式细胞仪检测壁层颗粒细胞凋亡情况,结果发现培养卵泡颗粒细胞的总凋亡率(早期凋亡+晚期凋亡)在8 h时就已达到70%以上,至24 h则为81.1%~94.6%。收集无血清培养0、8、16、24、48和72 h的卵泡颗粒细胞,用real time PCR SYBRgreen法检测各组卵泡颗粒细胞FasL和Fas mRNA相对表达量。各级卵泡颗粒细胞中FasL mRNA水平随培养时间显著增加,培养至24 h达最大值(P<0.05);小卵泡颗粒细胞FasL mRNA水平均高于大、中卵泡组。各级卵泡颗粒细胞Fas mRNA相对表达量在培养前(0 h)差异不显著,8 h时显著增加,48 h达最大值。该实验表明,所用无血清卵泡培养体系可有效诱导卵泡颗粒细胞的凋亡,细胞凋亡是卵泡闭锁的主要诱因,但卵泡闭锁程度可因卵泡大小而异,小卵泡似乎更容易发生闭锁。  相似文献   

10.
2000年至2009年,12只固定于10%福尔马林中非生殖系统疾病死亡的小熊猫卵巢组织,按常规组织学技术制作组织切片,HE染色,光学显微镜观察。结果:(1)不同发情时期卵巢均有原始卵泡、初级卵泡和次级卵泡分布。发情期的卵巢未观察到典型的成熟卵泡和卵母细胞;(2)原始卵泡数量较少,初级卵泡数量较多,多数初级卵泡和大多数的次级卵泡都处在闭锁状态;(3)卵泡腔出现之前,卵母细胞的直径和卵泡直径同时增长;卵泡腔出现之后,卵母细胞直径增长较慢,卵泡直径增长较快;(4)不同发情时期的小熊猫卵巢均存在大量的间质腺细胞;(5)妊娠小熊猫和发情间期无妊娠小熊猫的卵巢均有发育正常的黄体;(6)卵泡细胞发育呈低柱状至柱状时出现透明带。结论:(1)卵泡闭锁主要发生在初级卵泡阶段,仅少数卵泡能发育至次级卵泡;(2)卵母细胞和卵泡生长呈双相生长的趋势;(3)不同发情时期的小熊猫卵巢间质腺都发达;(4)发情排卵后,非妊娠黄体与妊娠黄体维持的时间相似,证实了小熊猫存在假孕现象。  相似文献   

11.
During May at Woods Hole, female Gasterosteus aculeatus periodically produce clutches of 112±19 eggs with an average diameter of 1·31±0·05 mm. The fish generally have primordial follicles ranging up to 0·56 mm diameter and a clutch of larger follicles undergoing synchronous growth. The size of oocytes within a growing clutch appears to be random within a population, which indicates that recruitment of clutches is not induced by a local environmental event. The largest oocytes within the population of primordial follicles have just begun vitellogenesis but are temporarily arrested. All oocytes within follicles larger than 1·1 mm diameter undergo spontaneous maturation and enlarge to preovulatory size when incubated at 16° C in a simple saline medium. Added deoxycorticosterone can induce similar events in somewhat smaller follicles placed in culture. Thus, in vivo , follicles grow from 0·56 to 1·1 mm diameter by vitellogenesis, and further enlargement is achieved by hydration during steroid-induced maturation. Females carrying follicles in maturational stages also have a new clutch of follicles entering vitellogenic growth from the population of primordial follicles. Injection of human chlorionic gonado-tropin causes a recruitment of follicles into vitellogenesis regardless of the stage of follicles within the growing clutch. One interpretation of these results is that when vitellogenic follicles reach a diameter of 1·1 mm a surge of gonadotropin(s) induces the follicle cells to release steroid, which results in oocyte maturation; the same surge also recruits a new clutch of vitellogenic oocytes. Qualitatively similar results were obtained for Apeltes quadracus ; thus the recruitment phenomenon observed for G. aculeatus may be a general feature among sticklebacks.  相似文献   

12.
Stressors (handling, chasing, and noise) applied randomly five times per day for one month to lizards during the recrudescence phase of the ovarian cycle caused a significant reduction in mean number of oocytes and primordial follicles when compared to those of controls. Further, vitellogenic follicles were absent in the ovary of lizards subjected to stressors. Administration of bovine FSH during post-breeding regression phase of the ovarian cycle induced ovarian recrudescence as shown by significant increases in the mean number of oogonia, oocytes, and primordial follicles compared to controls, as well as vitellogenic growth of follicles. However, lizards treated with FSH and exposed to stressors did not exhibit ovarian recrudescence. Furthermore, FSH administration during the post-breeding regression phase caused a significant increase in serum levels of estradiol compared to controls, which was accompanied by significant increases in the relative weight of the liver and oviduct, as well as vitellogenic growth of follicles. Despite administration of FSH to lizards subjected to stressors, there was neither any increase in serum levels of estradiol and weight of the liver nor vitellogenic growth of follicles. The results indicate that repeated application of stressors inhibits vitellogenic growth of follicles by suppression of steroidogenic activity in M. carinata. This is the first report revealing that the ovary does not respond to gonadotrophin treatment under stressful conditions in reptiles.  相似文献   

13.
Abdominal fat body mass of Calotes versicolor showed annual changes that were universal related to the changes in ovarian somatic (GSI) and hepatosomatic (HSI) indices. Fat bodies were absent in late breeding phase (June-August). Thirty day fatectomy (FBX) during prebreeding phase significantly reduced GSI, HSI, and total number of extrastromal follicles; also, recruitment of vitellogenic follicles was arrested and ateretic follicles increased. The FBX during postbreeding phase had no such effect, whereas in 30 day ovariectomised (OvX) lizards in prebreeding phase fat body mass significantly increased but HSI decreased. However, in lizards in prebreeding phase, E2 caused a significant decrease in fat body mass and an increase in HSI, while during the postbreeding phase there was a significant increase in HSI but the fat bodies were not affected. The above findings suggest that the development of the first clutch of vitellogenic follicles in the lizard utilises lipids stored in the fat bodies and that the growth of the subsequent clutches of vitellogenic follicles is met through the intake of food, which is abundant in the latter part of the breeding phase. The fat bodies are not needed for the growth of previtellogenic follicles. The fact that lipolytic action of E2 occurs only during the breeding phase suggests that responsiveness of the fat bodies to the steroid is related to the reproductive phase and that during postbreeding phase of the lizard they become refractory to E2.  相似文献   

14.
Apoptosis is a fundamental mechanism in follicular atresia and postovulatory regression in mammals, but its role in teleost ovarian function is currently unknown. This study tested the hypotheses that apoptosis mediates follicular atresia in teleosts and is inducible in vitro by incubation in serum-free conditions. Vitellogenic follicles from rainbow trout (Oncorhynchus mykiss) and goldfish (Carassius auratus) were incubated overnight in serum-free medium and examined for apoptosis by 3'-end-labeling and/or TUNEL analysis. Primary, postovulatory, and oocytectomized vitellogenic trout follicles and atretic goldfish follicles were evaluated in similar fashion. Overall, goldfish follicles had lower levels of DNA fragmentation than trout follicles. The DNA fragmentation in atretic goldfish follicles was similar to that measured in healthy vitellogenic and prematurational follicles; DNA fragmentation did not change after incubation. In the trout, postovulatory and oocytectomized vitellogenic follicles showed significantly greater in vitro susceptibility to apoptosis than intact vitellogenic follicles, whereas primary follicles were least susceptible. The TUNEL analyses revealed that in trout vitellogenic follicles, more thecal/epithelial cells than granulosa cells showed fragmented DNA in vivo, but incubation (24 h) did not result in increased apoptosis in cells of either type. These results indicate that apoptosis is involved in normal ovarian growth and postovulatory regression in teleosts, but that it does not appear to be an early event in teleost follicular atresia.  相似文献   

15.
The aim of this investigation was to identify the encoding sequence of vitellogenin receptor gene (vtgr), and its expression during the oogenesis in the spotted ray, Torpedo marmorata, in different phases of reproductive cycle. From an ovarian cDNA of vitellogenic female, we obtained a fragment of 581?bp, which corresponds to a partial sequence encoding the vitellogenin receptor (VTGR) in Torpedo (accession number: gi/193244760). This sequence shows a high identity with the VTGR of other vertebrates, particularly Leucoraja erinacea (89% identity) and Squalus acanthias (84% identity). We also showed that vtgr mRNA expression in the ovary modifies during the oogenesis and throughout the reproductive cycle. Indeed, in immature females, whose ovary contains only previtellogenic follicles, vtgr mRNA occurred in the oocyte cortex as well as within intermediate and pyriform cells. In mature females, whose ovary contains pre- and vitellogenic follicles, vtgr mRNA was detectable not only in the oocyte cortex and in intermediate and pyriform cells but also in small follicle cells present in the follicular epithelium of vitellogenic follicles. In ovulating females, that, as pregnant ones, show pre-and vitellogenic follicles, vtgr mRNA was evident in the oocyte cortex only, whereas in pregnant females, no vtgr mRNA was evident. The role of VTGR in the control of Torpedo vitellogenesis is discussed.  相似文献   

16.
The present investigation was conducted to determine the influence of dopamine (DA) receptor agonist bromocriptine (BRO) on reproduction and onset of puberty in the viviparous fish Gambusia affinis. In the first experiment, the mean number of stage I and II follicles (previtellogenic) in 0.8 or 5 mg BRO treated fish did not show significant difference compared to those of experimental controls, whereas the mean number of stage III follicles were significantly lower in 5 mg BRO treated fish compared to experimental controls. However, treatment of 0.8 or 5 mg BRO resulted in significantly lower numbers of stage IV (early vitellogenic) and V (late vitellogenic) follicles compared to those of experimental controls. There was decrease in the percent occurrence of pregnancy and different stages of embryos in BRO treated fish compared with the experimental controls. Concomitant with this, sparsely distributed gonadotropin releasing hormone immunoreactive (GnRH‐ir) fibres were observed in the proximal pars distalis (PPD) region of the pituitary gland in BRO treated fish compared to those of dense accumulations of these fibres in the PPD region of the pituitary gland in experimental controls. In the second experiment, exposure of juveniles (25 DPH) to same doses of BRO for 45 days resulted in complete absence of vitellogenic follicles and presence of few GnRH‐ir fibres in 5 mg BRO treated juvenile in contrast to presence of vitellogenic follicles and dense aggregation of GnRH fibres in treatment controls. Overall, the results of the present investigation suggest that DA affects ovarian follicular and embryonic development and onset of puberty in viviparous species.  相似文献   

17.
Unilateral ovariectomy (ULO, removal of one ovary) is a powerful technique for studying aspects of reproductive physiology, including follicular recruitment and growth. To examine effects of ULO for the first time in a semelparous species, coho salmon (Oncorhynchus kisutch) were unilaterally ovariectomized during mid-vitellogenesis approximately 3 months before spawning. At termination of the study (79 days post-surgery), single ovaries of ULO fish were gravimetrically equivalent to paired ovaries of sham surgery, control fish. There was no evidence of recruitment of new vitellogenic follicles. Instead, the dramatic increase in ovary mass was attributable to hypertrophy of existing vitellogenic follicles (33% increase in volume) and increased fecundity achieved through a greater than two-fold reduction in follicular atresia. The composition of whole ovaries on a dry weight basis from ULO fish was greater in protein, but lower in lipid than that of control fish. Expressing the data on a per follicle basis, however, showed that follicles of ULO fish contained more protein, ash, water, and lipid. The results indicate that ULO of coho salmon induces compensatory hypertrophy of existing vitellogenic follicles, while maximizing fecundity through reduction of atresia. Thus, 3 months before spawning, coho salmon exhibit the ability to adjust final egg size and number when faced with significant depletion of ovarian follicles. This in vivo system provides a platform for further study of physiological mechanisms regulating follicular growth and atresia, and the trade-off between egg size and egg number. J. Exp. Zool. 309A:468-476, 2008. (c) 2008 Wiley-Liss, Inc.  相似文献   

18.
The present study is an attempt to elucidate the involvement of insulin-like growth factor (IGF1) in the differentiation and growth of primary follicles in ovarian explant cultures of zebrafish. Ovaries from adult females were cultured in triplicate sets/treatment group for 15 days at 22°C in the laboratory. Culture medium was supplemented with either insulin (1 ng/mL) or IGF1 (1 ng/mL) or insulin + IGF1 (Experiment 1) or 0.1 or 1.0 or 10 ng/mL of IGF1 (Experiment 2). Ovaries cultured in medium alone served as controls and those fixed at the beginning of the culture as initial controls. Experiments were repeated. On the 16th day ovarian explants were fixed in Bouin’s fluid and processed for paraffin embedding, sections (3 µm) were cut and stained with hematoxylin-eosin. Follicles were classified into 6 stages and atretic follicles (AF). Previtellogenic, vitellogenic and total follicle number was calculated. At the start of the culture, ovaries contained all stages of growing and degenerating follicles. In in vitro cultured control ovaries, vitellogenic follicles underwent atresia, while, primary follicles remained unaffected. Insulin or insulin + IGF1 treated ovaries did not differ significantly while IGF1 exposed ovarian explants had greater (P < 0.05) number of primary follicles compared to controls. IGF1 also caused an increase in the number and growth of primary follicles in a dose dependent manner although; cultures were not supplemented with gonadotrophic hormones. Results suggest that locally derived intra-ovarian IGF1 may have a role in the differentiation and growth of primary follicles in zebrafish ovary.  相似文献   

19.
Follicular development in snapping turtle, Chelydra serpentina, was studied in relation to changes in plasma levels of estradiol-17 beta, total protein, calcium, inorganic phosphate and cholesterol. Histochemical reaction for 3 beta-HSD in granulosa and theca cells of the follicles is strong during the preovulatory and vitellogenic phases when the follicles attain their maximum size (18-22 mm) and estradiol is at a high level. The reaction for 3 beta-HSD is weal during the postovulatory phase when the developing follicles are at their minimum size (5-7 mm) and estradiol is low. Administration of estradiol-17 beta causes a rise in plasma calcium, total protein, inorganic phosphate and cholesterol.  相似文献   

20.
The opioid peptides are involved in the regulation of neuroendocrine functions in vertebrates. Nonetheless, the influence of an opioid peptide, dynorphin A (DYN), on reproduction in fish is understudied. The aim of this work was to study the influence of DYN on the pituitary-ovary axis in Oreochromis mossambicus. Daily injections (ip) of 250 μg DYN kg−1 body weight for 22 days during the ovarian cycle caused a reduction in the intensity and the per cent area of luteinizing hormone (LH) immunoreactive content in the proximal pars distalis region of the pituitary gland compared with an intense immunostaining in time-matched controls. In the ovary, DYN treatment caused a decrease in the number of stage I (previtellogenic) follicles compared with time-matched controls. No difference was observed in the number of stage IV (vitellogenic) follicles among different experimental groups, whereas the numbers of stage II and stage III follicles (previtellogenic) were higher in DYN-treated fish than in time-matched controls. Nonetheless, there was a reduction in the number of stage V (preovulatory) follicles in DYN-treated fish compared with time-matched controls. Taken together, these results indicate that DYN exerts an inhibitory effect on follicular recruitment at the late vitellogenic stage, through the suppression of LH secretion in fish.  相似文献   

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