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选取健康麻鸭进行同种异体卵巢移植，移植后测定45日龄、75日龄、105日龄、开产日龄、开产后30日龄和开产后60日龄时血浆促卵泡素（FSH）、促黄体素（LH）、雌二醇㈤水平；并且在产蛋期内不同的时间获取各个级别卵泡的颗粒细胞，检测其凋亡率。结果显示，移植后FSH、LH、E2的分泌均高于对照组，在开产30日龄时差异显著，表明移植成功并且卵巢发育良好，卵巢功能正常；移植后各级卵巢颗粒细胞凋亡率显著低于对照组，并且随着卵泡直径的增加，颗粒细胞的凋亡率呈现下降的趋势，表明卵巢移植可以降低卵泡颗粒细胞凋亡率。结论：同种异体卵巢移植卵巢发育良好，具用正常的分泌功能，可以降低卵泡颗粒细胞的凋亡率。 相似文献
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本试验采用TUNEL原位法和DNA梯度电泳法等方法对卵巢上闭锁卵泡中凋亡的颗粒细胞类型和分布状况等进行研究。结果表明，辽宁绒山羊闭锁卵泡是细胞凋亡引起的。DNA梯状电泳表明，不同健康程度卵泡颗粒细胞凋亡程度不同；而颗粒细胞TUNEL原位标记表明，健康卵泡、轻度闭锁卵泡及闭锁卵泡中颗粒细胞凋亡比例分别为13.21%±1.23％、32.13%±2.13％、51.31%±3.02％；不同健康程度卵泡中类固醇激素水平不同，健康卵泡中E2水平较高，孕酮浓度较低；闭锁卵泡中E2浓度较低，P4浓度较高，健康、轻度闭锁和闭锁三类卵泡中E2/P4比值分别是2.62±0.03、0.074±0.0003、0.028±0.0004。 相似文献
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为探讨孕马血清促性腺激素（PMSG）对2－3月龄性未成熟的小母猪卵巢中卵泡发育，卵泡闭锁以及卵泡颗粒细胞凋亡的影响，就其注射PMSG后24，48，72，96h卵巢中各类卵泡数量，颗粒细胞凋亡比例及外周血浆中类固醇激素水平等进行了研究。结果如下：（1）未注射PMSG前，性未成熟小母猪卵巢表面卵泡总数（10．5个／卵巢）及各类卵泡数（小卵泡9个／卵巢，中等卵泡数1．5个／卵巢）均较少；注射PMSG后24h，小卵泡数（24个／卵巢），中等卵泡数（6．5个／卵巢）和大卵泡数（1．5个／卵巢）与对照组相比均明显增多；至注射PMSG后96h，小卵泡（4．5个／卵巢）和中等卵泡数（1．5个／卵巢）均明显减少，但大卵泡数量仍较多（4．5个／卵巢）。（2）未注射PMSG前，性未成熟小母猪中类卵泡中的颗粒细胞凋亡比例均较高，小卵泡和中等卵泡分别为24．8％和34．4％；注射PMSG事24h，颗粒细胞凋亡比例显著降低（P＜0．05），小卵泡和中等卵泡分别为10．7％和13．7％，至PMSG事72h，小卵泡和中等卵泡的颗粒细胞凋亡比例开始显著升高（P＜0．05），而大卵泡在出现后颗粒细胞凋亡比例较低且无较大波动。（2）在未注射PMSG前，血清中的雌二醇含量仅为15．3ng/L，孕酮则由于含量大低而未能检测到；在注射PMSG后，雌二醇和孕酮水平均升高，雌二醇在注射PMSG后72h时达最高值59.2ng/L，孕酮在注射PMSG后48h出现最高值1.7 μg/L。以上结果表明，在性未成熟的2－3月龄小母猪，卵泡颗粒细胞凋亡比例很高，导致卵巢表面各类卵泡数量均较少，血清类固醇激素水平也很低，而PMSG可在其尚未建立起自身下丘脑－垂体－性腺轴的激素调节机制情况,显著抑制颗粒细胞亡，从而抑制卵泡的闭锁，促进卵泡的发育，并进而提高血清中类固醇激素的水平。 相似文献
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卵巢是家禽的重要繁殖器官,会产生大量卵泡,而卵泡在生长发育的各个阶段中都可能因为不同因素的调控而发生闭锁,最终导致繁殖性能衰退。颗粒细胞对卵泡的生长发育有重要调控作用,其凋亡会诱导卵泡发生闭锁。诱导颗粒细胞发生凋亡的因素较多,包括激素、细胞因子、氧化应激、线粒体及其他体外因素。颗粒细胞凋亡主要由线粒体途径导致,其涉及到半胱天冬酶（Caspase）家族参与,当线粒体裂解时会释放细胞色素C （Cyt-C）,随后形成凋亡小体激活Caspase-3和Caspase-8,最终激活Caspase-9导致颗粒细胞凋亡;当颗粒细胞发生凋亡,家禽体内卵泡丧失生物功能并且卵泡细胞之间的调控失衡,促使卵泡内卵母细胞和膜细胞凋亡,最终导致卵泡发生闭锁;颗粒细胞在存活状态下所分泌的生长因子、性腺类固醇、细胞因子能减少卵母细胞氧化损伤,防止细胞内活性氧（ROS）水平过高导致的线粒体DNA损伤,从而避免线粒体功能障碍而造成的颗粒细胞凋亡。作者从颗粒细胞凋亡及其影响因素、颗粒细胞凋亡和卵泡闭锁的关系、颗粒细胞凋亡对卵泡闭锁的影响3个方面进行阐述,以期为减少卵泡闭锁、提高家禽繁殖性能提供理论依据。 相似文献
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为了解水牛有腔卵泡闭锁的起因和有腔卵泡中是否存在卵泡颗粒细胞凋亡，本研究选择青春期前水牛和成年（发情间期和发情期）水牛的卵巢，采用石蜡组织切片、HE染色技术进行光镜观察，并采用DNA原位末端标记（TUNEL）技术和透射电镜观察研究了卵泡颗粒细胞凋亡的特征。结果表明：青春期前水牛的健康有腔卵泡上无或仅有极个别凋亡的卵泡颗粒细胞（GCs），而闭锁有腔卵泡上存在有多量凋亡的GCs，凋亡的形式：GCs层内出现单个或多个凋亡细胞，卵泡腔内出现凋亡小体群。在成年水牛发情间期的闭锁大卵泡上，GCs层弯曲皱折，存在多量凋亡的GCs。发情期水牛成熟卵泡的GCs层也存在GCs凋亡，排卵前的GCs层细胞全部脱落到卵泡腔内。本研究首次在同一组织切片上先后分别应用HE染色和TUNEL检查细胞凋亡，且证实了水牛有腔卵泡GCs凋亡的存在。超微结构显示了GCs凋亡的核边集化、核浓缩及凋亡小体的形态。上述结果提示：在水牛闭锁有腔卵泡中存在着GCs凋亡，GCs凋亡是启动水牛有腔卵泡闭锁的潜在机理。 相似文献
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为了解水牛卵巢卵泡中颗粒细胞（GCs）和卵母细胞在体外培养过程中发生凋亡的变化特征,通过体外培养、血清撤除法诱导水牛卵泡GCs凋亡,并应用苏木精伊红（HE）染色和DNA原位末端标记的TUNEL方法观察其病理特征;通过水牛腔前卵泡体外培养、诱导或等待其中的卵母细胞及卵泡细胞发生凋亡,然后应用透射电镜技术检查其超微结构改变。结果显示：凋亡卵泡GCs的HE染色特征包括细胞体积缩小,染色较深呈紫黑色,且多成簇分布。DNA原位末端标记检查的特征是DNA发生降解,其降解碎片呈TUNEL阳性。原始卵泡体外培养中调亡卵母细胞的超微结构表现为胞核碎裂成电子密度高的大碎片,或出现形态奇特的凋亡小体;初级卵泡中的调亡GCs,细胞内外均出现凋亡小体,细胞内还见有典型的螺层状内质网结构,其中包涵部分核质。 相似文献
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根据已发表的Bcl-2基因序列设计3对siRNA（Small interference RNA）序列，构建干扰表达载体，转染体外培养的鹅卵泡颗粒细胞，48h后利用流式细胞术（Flow cytometry，FCM）检测颗粒细胞Bcl-2蛋白表达量、凋亡和增殖情况，收集细胞培养液用放射免疫分析法检测孕激素（P）的分泌水平；此外，还检测了F1～F4卵泡、最小的排卵前卵泡（The smallest preovulatory follicle，SPF）、小黄卵泡（Small yellow follicle，SYF）和闭锁卵泡（Atresic follicle）颗粒细胞Bcl-2蛋白表达和凋亡情况。结果表明：（1）各级卵泡颗粒细胞Bcl-2蛋白的表达存在着差异，正常卵泡颗粒细胞Bcl-2蛋白表达量显著高于闭锁卵泡（P〈0．05），SPF颗粒细胞Bcl-2蛋白表达水平显著高于SYF（P〈0．05）；（2）干扰组Bcl-2蛋白表达水平显著低于所有对照组（P〈0．05），而细胞凋亡指数（Apoptosis index，AI）、增殖指数（Proliferation index，PI）和P分泌水平均高于对照组。 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献