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151.
麻醉和手术对母山羊垂体内分泌功能的影响   总被引:4,自引:0,他引:4  
在给母山羊注射846麻醉注射液或实施外科手术前后收集颈静脉血样,监测846麻醉注射液或外科手术对垂体促性腺激素分泌的影响。结果表明,846麻醉注射液对山羊垂体LH和FSH分泌无显著影响(P>0.05);但外科手术对LH和FSH分泌影响显著(P<0.05),在手术期间血浆LH和FSH水平较手术前显著降低(P<0.05),而在手术结束后,血浆LH和FSH水平又升高,与手术前差异不显著(P>0.05)。  相似文献   
152.
This study aims to investigate the effects of follicle stimulating hormone (FSH) and fibroblast growth factor-2 (FGF-2) on the survival and growth of caprine preantral follicles. Ovarian tissues were cultured for 1, 7, 14, 21 or 28 days in medium supplemented with FSH (FSH-2d or FSH-7d, i.e., with replacement of the culture medium every 2 or 7 days, respectively) or FSH + FGF-2 (replacement of the medium every 2 days). Non-cultured (control) and cultured ovarian fragments were processed for histological and ultrastructural analysis. After 28 days of culture, the media supplemented with FSH-2d was the most effective in maintaining the percentage of normal follicles and in promoting follicular growth. Furthermore, both treatments with FSH increased the percentage of the primary follicles. However, ultrastructural studies did not confirm follicular integrity from 14 days of culture onward. In conclusion, culturing tissue for up to 7 days in medium containing FSH alone or combined with FGF-2 maintains caprine preantral follicle integrity and promotes their growth in vitro.  相似文献   
153.
The aim of present study was to clarify the post-natal profile of follicle-stimulating hormone (FSH), luteinizing hormone (LH), immunoreactive (ir)-inhibin, progesterone, testosterone, and estradiol-17β, and their relationships in Thoroughbred colts. Six hundred and thirty-six colts were used for the study. Single plasma samples from each animal were harvested from the blood drawn through jugular venipuncture. The subjects were born with high amounts of progesterone, testosterone, and estradiol-17β, all of which dropped significantly and remained at lower levels till the end of 6 months. FSH decreased transiently after birth until day 12 and then gradually increased to peak at day 100 which then maintained in lesser levels towards the end of the studied period. LH was highest during birth which decreased until day 26 and then increased slowly to sub-birth levels up to day 90. Animals were born with high amounts of ir-inhibin. It dropped slowly and halved by day 20 and then decreased towards rest of the studied period. The increase in FSH is negatively correlated with the declining ir-inhibin levels. The early increase in FSH can be the indication of early post-natal maturation of the hypothalamic pituitary testicular axis that ultimately might be responsible for priming the testes for future development.  相似文献   
154.
Puberty is the process by which animals acquire for the first time the ability to reproduce. In teleost fishes, an understanding of the mechanism underlying pubertal development is important not only for basic science but also for aquaculture. In this article, recent progress in several aspects of puberty in teleosts is reviewed; namely, pubertal changes in brain-pituitary-gonad axis, factors controlling the timing of the onset of puberty, and artificial control of puberty. In addition, possible future directions of study are suggested. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
155.
The changes in catalase activity in carp (Cyprinus carpio) ovarian follicles at different developmental stages were investigated. The effect of follicle-stimulating hormone (FSH) on catalase activity and estradiol secretion by carp ovarian follicles was studied to establish a developmental role of catalase in folliculogenesis in fish ovary. The follicular homogenates from large follicles showed higher (9.45 ± 0.64 units/mg protein) catalase-specific activity than the small follicles (2.94 ± 0.22 units/mg protein). The FSH significantly (P < 0.05) stimulated the catalase activity in both size categories of the follicles in vitro. At the dose level of 100 ng FSH/ml culture medium, about 38 and 25% increase in catalase-specific activity was observed compared with the respective controls in small and large follicles respectively. The increase in catalase after FSH treatment was also accompanied by a similar increase in estradiol secretion. This study indicates that catalase might play a functional role in carp ovarian follicles.  相似文献   
156.
对家兔超数排卵及胚胎移植若干问题的探讨   总被引:10,自引:3,他引:10  
采用FSH、LH对日本大耳白兔分组进行不同的处理,对所使用的FSH的总剂量、卵子回收率等问题作一探讨。结果表明:1.5岁以上经产母兔使用FSH总剂量以40~50IU为好,1.5岁以下经产母兔和青年兔以20IU为好;经产母兔比青年母兔超排效果好,青年兔较经产母兔卵子回收率高。  相似文献   
157.
用不同方法对不同年龄的家兔超排效果比较   总被引:11,自引:0,他引:11  
本研究采用了FSH+hCG和FSH+LH两种超数排卵处理方法对本地白兔分组进行了超排试验。结果表明:(1)对本地白兔采用FSH+hCG超排处理方法较FSH+LH超排处理方法超排效果好;(2)本地经产母兔比青年母兔超排效果好。本试验为利用本地白兔进行转基因、胚胎移植等相关方面的科学研究进行了初步工作。  相似文献   
158.
为了认识动物胎儿期垂体 性腺轴调节机制的发生 ,本研究建立了绵羊促卵泡刺激素 (FSH)的生物学测定方法 ,并用该方法测定和研究了绵羊不同发育时期的胎儿及母体血浆中促卵泡激素FSH含量 (B FSH)。结果证明 ,在绵羊胎儿发育的早期 (6 0d) ,血浆中B FSH含量较低 ,但在中期 (6 0~ 12 0d)显著升高 (P <0 0 5 ) ,而后期至羔羊新生期显著降低 (P <0 0 5 )。雄性胎儿中期血浆B FSH含量显著高于雌性胎儿 ,其他时期无显著的性别差异。在妊娠 6 0~ 90d间 ,母体血浆FSH较高 ,之后显著降低 (P <0 0 5 )并持续到出生期。在胎儿发育过程中母体血浆中B FSH的变化与胎儿血浆B FSH的变化无显著的相关性。  相似文献   
159.
Several successful in vitro culture experiments have used oocyte-cumulus cell-mural granulosa cell complexes (OCGCs) from early antral follicles (0.5–0.7 mm) for the growth of bovine oocytes. However, in studies related to in vitro oocyte maturation and in vitro embryo production, oocyte-cumulus cell complexes (OCCs) that have no mural granulosa cells have been widely used instead of OCGCs. The purpose of this study was to determine whether cumulus cells alone support oocyte growth. First, OCCs and OCGCs were cultured in vitro for 14 days to compare the integrity of the complexes as well as antrum formation. After 14 days, the diameter and meiotic competence of oocytes in OCCs and OCGCs were examined. Oocytes in OCCs grew fully and acquired meiotic competence similar to OCGCs, whereas antrum formation occurred later in OCCs as compared to OCGCs. Subsequently, the effects of follicle stimulating hormone (FSH) on in vitro growth of OCCs were examined for 14 days. When FSH was added to the culture medium, OCCs formed antrum-like structures one day earlier than those cultured without FSH. Oocytes cultured with 1 mIU/ml FSH grew fully and acquired meiotic competence. In contrast, when oocytes were cultured in media containing high concentrations of FSH, some of the OCCs collapsed and the number of degenerated oocytes increased. In conclusion, bovine oocytes in OCCs grow and acquire meiotic competence similar to OCGCs and, 1 mIU/ml FSH supports the development of OCCs and oocyte growth as observed in our culture system.  相似文献   
160.
用7个剂量(37 ̄132IU)FSH对10只波尔山羊进行超数排卵处理,试验结果表明,波尔山羊这一品种对垂体促卵泡激素FSH极为敏感。使用60 ̄132IU剂量处理的5只母羊,均表现激素过量现象,冲出卵子均未受精;使用37 ̄44IU剂量处理的另5只母羊,均冲出受精卵,共采集可用胚72枚,其中2只使用42IU剂量处理的母要集到可用胚30枚和23枚,效果最佳。采集到胚胎用手术移植受体羊52只,妊娠36只,妊娠率69.2%。  相似文献   
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