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羊驼生殖器官的解剖与生殖生理学特性 总被引：1，自引：0，他引：1
综述了羊驼生殖器官的解剖结构与发情、排卵、交配、妊娠和分娩等生殖生理学特征及生殖相关问题。雄性羊驼生殖器官主要特征是睾丸相对较小,缺精囊腺,阴囊位置靠近肛门,阴茎为纤维性类型,阴茎形成S形弯曲,交配时伸出包皮,包皮口朝后,排尿时尿流向后方。雌性羊驼生殖器官主要特征是子宫为双角子宫,子宫颈皱襞不发达,子宫黏膜结构与猪和马的相似。羊驼为单胎动物,交配诱导排卵,通常是单个排卵,即仅有一个卵泡破裂。雌性羊驼无明显的发情表现,性成熟母羊驼空怀状态随时接受交配,交配为卧式交配。妊娠率较高,妊娠与否可以通过多种妊娠检测方法来确定;自然情况下很少有难产发生,遇有特殊情况才需要助产。 相似文献
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氯前列烯醇系前列腺素F２a的类似物，在乳牛繁殖生产上用于控制母牛同期发情，调节乳牛的繁殖时期，做到集中配种、集中分娩。在胚胎移植时使受体牛与供体牛同步发情，另还可用于母牛非正常妊娠的人工引产，在临床用的最多的还是牛繁殖疾病的治疗。现将几年来笔者应用该药治疗乳牛持久黄体、黄体囊肿、人工引产、子宫蓄脓等病例的体会报道如下：１持久黄体持久黄体也称永久黄体滞留，是指母牛在分娩后或性周期排卵后，妊娠黄体或发情性周期黄体及其机能长期存在而不消失。主要表现性周期停止、母牛长期不发情等不孕症。笔者临床治疗６例，… 相似文献
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在激素中，与动物性器官，性细胞，性行为的发生和发育以及发情，排卵，妊娠，胚胎发育，分娩，泌乳等生殖活动有直接关系的激素．统称为生殖激素。[第一段] 相似文献
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毛殿江 《畜牧兽医科技信息》2012,(1):54
公、母羊生长发育达到一定年龄,生殖器官发育基本完全。母羊具有成熟的卵子和排卵能力,有交配的欲望和能力,若在发情时配种就能受胎。1发情征状季节性发情的绵羊品种,到繁殖季节就有发情征状,公羊表现为紧紧追赶母羊,用鼻嗅母羊或用腿扒母羊后躯,以及爬跨母羊等。母羊大多数发情不明显,当公羊追赶时,母羊表现为喜欢接近公羊、站立不动,有时两腿分开,摇动尾巴, 相似文献
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犬发情、排卵鉴定方法及最适配种时间确定 总被引：3，自引：0，他引：3
母犬发育到一定年龄时，所表现的一种周期性活动现象叫发情，最明显的征兆是阴户流出血样分泌物，允许公犬交配，卵巢有卵子排出。准确把握排卵时间，适时交配是提高受孕率的关键。母犬的发情活动有周期性，从一次发情开始到下一次发情开始，或由这一次排卵到下一次排卵的间隔期称为性周期。犬的性周期具有特殊性，它不是发情周期的重复。发情周期一般分为发情前期、发情期、发情后期、无发情期。无发情期期间的生殖器官呈休止状态。根据卵巢情况，犬的性周期尚可分为卵泡发育、成熟、排卵的卵泡期和排卵后形成功能性黄体的黄体期以及功能黄体变性、退化的卵巢静止期。 相似文献
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随着产业结构的调整,以草养畜的兴起,草食家畜饲养量上升。为提高经济效益,必须提高繁殖力。乳牛配种后及早进行妊娠诊断,对妊娠牛及时采取保胎措施;对未妊娠牛采取补配,从而减少空怀,缩短产犊间距;对确诊为生殖器官疾患者,采取及时治疗,尽早恢复繁殖能力或淘汰。妊娠诊断的方法如下:1直肠检查法通过直肠检查,触摸卵巢和子宫,依其形态判定妊娠否。1.1卵巢上的黄体形态对比法以牛发情配种后15天排卵侧卵巢上的黄体形态为基准,在配种后17、19、21天分别检查1次,若对比卵巢上的黄体形态与15天相同,则表示妊娠。若缩小,则未妊娠。此法的准确率一… 相似文献
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O J Ginther 《Equine veterinary journal》1990,22(3):152-156
Prolonged luteal activity is one of the most formidable terminology challenges in mare reproductive biology. Prolonged luteal activity can be a result of persistence of an individual corpus luteum or the sequential development of luteal glands, each of which may have a normal life span. Luteal tissue can originate from an unovulated follicle or from an ovulation occurring during either follicular or luteal dominance. These complexities, together with ambiguous and inconsistent terminology, have resulted in confusion regarding those conditions which can be grouped broadly under the term prolonged luteal activity. Persistence of an individual corpus luteum can occur in association with severe damage to the endometrium resulting in loss of the uterine luteolytic mechanism. Spontaneous (no known uterine pathology) persistence of the corpus luteum from the follicular-phase ovulation has not been documented adequately as a clinical entity. The occurrence of ovulation towards the end of dioestrus may cause confusion about the origin of prolonged luteal activity. Such immature dioestrous corpora lutea may not respond to the release of uterine luteolysin, thereby leading to prolonged luteal activity even though the original corpus luteum regressed at the normal time. In the absence of critical monitoring of the corpus luteum (eg by ultrasound) the prolonged activity could be attributed erroneously to persistence of the corpus luteum from the follicular-phase ovulation. Pseudopregnancy is another confusing term that is sometimes used to describe persistence of the corpus luteum, especially when the luteal persistence is caused by embryonic loss after the embryo has blocked the uterine luteolytic mechanism.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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哺乳动物发情周期黄体的组织学研究进展 总被引：1，自引：0，他引：1
黄体是排卵后形成的暂时性的内分泌组织 ,在一个较短的存在期限中经历了一系列的结构变化和分泌阶段 ,对于哺乳动物维持正常的生殖功能具有重要作用。人们对黄体细胞的来源、组成、形态及大小持有不同的观点。近年来 ,人们就黄体细胞的功能和退化、溶解进行了较为深入的研究 ,发现不同动物黄体细胞的功能各有不同 ,黄体退化、溶解与细胞凋亡有密切关系。了解哺乳动物发情周期黄体的组织结构对于控制动物的繁殖具有重要意义。文章对哺乳动物发情周期黄体中不同类型黄体细胞的来源、组成、形态、功能及退化、溶解 ,黄体细胞的分泌方式和超声波在黄体研究中的运用作了概述 相似文献
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Ultrasonography is useful for monitoring the dynamic follicular and luteal changes of equine ovaries, since it permits rapid, visual, non-invasive access to the reproductive tract. A 5 MHz transducer has greater resolving power and is far more suitable for evaluation of ovaries than a 3–3.5 MHz transducer. Follicles as small as 2–3 mm can be seen and the corpus luteum can usually be identified throughout its functional life. In a study involving daily ovarian examinations, there was a pronounced change in shape of the preovulatory follicle from a roughly spherical to a pear-shaped or oblong form in 66% of the ovulatory periods, This change usually occurred on the day preceding ovulation. The occurrence of ovulation was detectable by the disappearance of a large follicle. In addition, the ovulation site on day 0 was characterized by an intense echogenic area in 88% of 32 ovulations. The developing corpus luteum retained the echogenicity for a mean of 2.4 days. In a blind study, the location of the corpus luteum, as determined by ultrasound, agreed with a previous independent determination of the side of ovulation by palpation in 88% of the 40 bred mares on days 0–14. In all of the 12 mares that were in estrus, the location of the corpus luteum could not be ascertained. In another study, the corpus luteum was identified for a mean of 16 days in 14 estrous cycles. One or more days before the corpus luteum became ultrasonically unidentifiable, it developed increased echogenicity in 36% of the mares, indicating greater tissue density. It is concluded that ultrasonic evaluation of the corpus luteum is superior to digital evaluation by rectal palpation. Some of the potential applications of ultrasonic examination of the ovaries include: 1) obtaining important, sometimes definitive, information by a single examination for judging whether a mare has entered the ovulatory season, 2) aiding in estimating the stage of the estrous cycle, 3) detecting double preovulatory-sized follicles which are in close apposition and difficult to discern by palpation, 4) detecting failure of ovulation or anovulatory estrus by the absence of a corpus luteum, 5) differentiating a persistent corpus luteum from anovulatory or anestrous conditions, 6) diagnosing certain pathological conditions such as peri-ovarian cysts and ovarian tumors, and 7) diagnosing anovulatory hemorrhagic follicles. 相似文献
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为研究排卵延迟奶牛发情配种后黄体的变化规律及其差异性,本研究在临床症状观察、直肠检查和B超辅助检查诊断的基础上,选取8头排卵延迟奶牛(排卵延迟组)、5头健康正常发情奶牛(对照组),应用B超对黄体的相关指标(直径、面积、周长和体积)进行了测量及分析,对获得的不同阶段典型黄体声像图进行了描述。结果显示,与对照组相比,排卵延迟组与对照组奶牛黄体的直径、面积、周长和体积在发情配种后7~15 d差异均不显著(P>0.05)。在发情配种后第9和13天排卵延迟组奶牛黄体相关指标(直径、体积、面积和周长)大于对照组奶牛,而在第11天小于对照组奶牛。结果表明,排卵延迟奶牛发情后不同阶段B超黄体直径、面积、周长和体积与正常发情排卵后的相应指标没有显著差别。 相似文献
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The study was aimed to observe the variation and differences of corpus luteum of delayed ovulation cows after estrus.Based on the observation of clinical symptoms, rectal examination and diagnosis of B-ultrasound scanning, 8 delayed ovulation dairy cows with the variation (delayed ovulation group) and 5 healthy and normal dairy cows with estrus (control group) were selected, and the related indicators of the corpus luteum (diameter, area, perimeter and volume) were measured by B-ultrasound scanning.These luteal indicators were compared and analyzed further, and the luteal typical sonography obtained of the different stages were described.The results showed that the diameter, area, perimeter and volume during 7 to 15 d after estrus of the corpus luteum had no significant differences between delayed ovulation group and control group (P>0.05).However, on the 9th and 13th day after estrus, the luteal relevant indicators of delayed ovulation group cows (diameter, volume, area and perimeter) were greater than that of control group cows and less than normal dairy cows on the 11th day.There were no significant differences in diameter, area, circumference and volume of corpus luteum at the different stages after estrus between the delayed ovulation dairy cows and the normal ones. 相似文献
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Plendl J 《Anatomia, histologia, embryologia》2000,29(5):257-266
Angiogenesis is prominent during development and downregulated in the adult. Strictly controlled angiogenesis in the healthy adult occurs cyclically in the ovary and corpus luteum, which therefore make an excellent model with which to study vascular growth. Dysfunctional or uncontrolled angiogenesis is involved in a number of diseases and is responsible for growth and dissemination of tumours. This review focuses on the following aspects of the ovary: the gross and microscopical anatomy of the blood vessels, described mainly--but not exclusively--in the bovine; vascularization of the follicle before and after ovulation; angiogenesis in the developing and the mature corpus luteum as well as in the corpus luteum of pregnancy. The potential mechanisms of vascular regression during luteolysis and the potential role of vascular growth in dominance and atresia of follicles will be described. Furthermore, recent research on ovarian angiogenic and potential anti-angiogenic factors including fibroblast growth factor (FGF), vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF), angiopoietin and metalloproteinase inhibitor will be presented. Finally, the role of hormones including FSH, LH, sexual steroids, prostaglandins, prolactin, oxytocin and activin/inhibin in ovarian angiogenesis will be summarized. Future research is likely to yield valuable information that can contribute to the development of novel therapeutic strategies for the treatment of diseases characterized by disregulated angiogenesis and vascular regression. 相似文献
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The cyclic related growth and regression of the corpus luteum during four consecutive oestrous cycles of the regular four-day-cycling (ie, 16 days), virgin albino Wistar rat were followed up by light and electron microscopic investigation of the ovaries. After ovulation, follicular granulosa cells differentiated into luteal cells in the newly formed corpus luteum. Based on their specific histological characteristics, four various types of corpus luteum in each stage of the oestrous cycle could be identified. As soon as the luteal cells started to degenerate, the number of fibroblasts progressively increased and apoptotic degeneration of luteal cells was initiated and became most prominent during oestrus. Complete regression of the corpus luteum was seen after 15 days. This study shows a strictly organised pattern of luteal cell growth and degeneration in the corpus luteum of the regular four-day-cycling, virgin Wistar rat. The morphological alterations may be regulated by a hormonal fluctuation. 相似文献
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黄体释放的黄体酮对母畜发情周期、启动发情行为和维持妊娠起着至关重要的作用,但目前国内外对黄体是否影响胚胎移植效果有着不同报道。本文以探究黄体对牛胚胎移植效果的影响为主线,查阅大量文献,归纳黄体的检查和级别判断方法,分别分析黄体大小、黄体位置、黄体质量和黄体生产溶解过程激素水平与胚胎移植受胎率的关系,为提高胚胎移植效果提供科学的参考依据。生产上常通过B超扫描结合直肠检查法判断受体牛黄体发育和位置作为能否移植的依据;由各学者研究结果可见,不同直径黄体的胚胎移植受胎率差异不显著,为提高受体牛的利用,在对受体牛黄体大小选择时可适当放宽标准;胚胎移植到黄体同侧的受胎率比移植到黄体对侧的高,另外,可能因为操作者左右手操作习惯不同,发现左侧黄体移植受胎率比右侧的要高;较多学者认为质量好的胚胎选择黄体质量好的受体移植才能得到更高的受胎率;胚胎移植后能否成功受孕,还与黄体生成溶解过程中孕酮含量及孕酮与雌二醇的比例等有关。 相似文献
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Kornmatitsuk S Kornmatitsuk B Chantaraprateep P Larsson B 《Tropical animal health and production》2009,41(3):337-344
The aims of the current study were to illustrate figures for the characteristics of oestrous cycles especially on follicular
dynamics, corpus luteum and changes in progesterone and prostaglandin F2alpha, in the Holstein cross-bred dairy heifers. Twenty
six healthy and sexual-mature virgin heifers were monitored for signs of oestrus. Their ovaries were sonically examined and
the numbers and the sizes of the follicles as well as of the corpus luteum were documented. In our study, no difference in
ratio of the 2-wave and 3-wave patterned cycle was evident. Seasons' change did not affect on characteristics oestrous cycles
as well as on dynamics of follicles and corpus luteum. The heifers showed high variation in manifesting oestrus especially
on a number of hours. The ‘bodily’ oestrous signs lasted longer than did ‘behavioural’ signs and connection of lowering of
the back to standing oestrus was established. Certain diversities comparing to of existed dairy breeds were drawn for follicular
dynamics, corpus luteum and its progesterone: 1) the 1st an-ovulatory dominant follicles showed higher growth rate and earlier
exceeded dominant diameter; 2) the follicle tended to quicker ovulate but with a smaller diameter at ovulation; 3) the corpus
luteum exhibited 4−16.5 mm in diameter of central cavity. Connecting to the levels of progesterone, 4) the corpus luteum turned
into active, as well as mid-luteal, period quite late, and 5) the duration of the active period of the corpus luteum was shorter,
but 6) at the end of the cycle –around the day of oestrus, progesterone remained certain low but significant levels. In conclusion,
the Holstein cross-bred dairy heifers in our study faced a problem of delayed post-ovulatory progesterone rise of which underlying
causes are needed to be further scrutinised either at endocrine or at cell levels. 相似文献