催产针要慎用

在生产实践中,经常会碰到母畜(尤其是初产母畜)难产现象。有的饲养员或初学兽医人员,为求快些结束分娩,喜欢用“催产针”来催产。其实催产针的使用是有一定的适应症的,如使用不当,不仅催产不成,反而会造成子宫破裂。1作用机理最常用的催产针是催产素(缩宫素),它主要是通过加强子宫平滑肌的收缩而起催产作用。但是,子宫在催产素作用下的收缩强度及收缩性质,随着子宫的生理状态和用药剂量的不同而不同。简单说,妊娠早期子宫对催产素不大敏感,随着妊娠进展,子宫对催产素的敏感性逐渐增强,临产时达到高峰,产后又逐渐减弱。小剂量的催产素能使子…     

正确使用催产素治疗母猪难产

催产素形成于丘脑下部的室旁核,并且呈滴状沿丘脑下部--垂体后叶径中的轴突运送到垂体后叶贮存.在分娩过程中,由于来自子宫和产道的刺激,可导致催产素的释出.催产素有兴奋子宫平滑肌,引起子宫收缩从而发生分娩作用.当母猪因体内催产素含量较低,子宫收缩微弱而引起难产时,可用催产素催产. 1.催产素对子宫的收缩作用以临产及刚分娩后较为敏感,无分娩预兆时催产无效. 2.由骨盆狭窄、产道受阻、胎位不正等引起的难产或有剖宫产史的母畜禁用,否则可能因子宫剧烈收缩而发生破裂死亡. 3.猪胎盘属于弥散型胎盘,胎儿胎盘和母体胎盘的联系不紧密.子宫的强烈收缩容易使二者引起分离.如果胎儿不能很快产出,就可能缺氧死亡.在临床上常可见到使用催产素治疗难产时产出死胎较多.所以催产素使用剂量要适宜.一般每次20～40IU,根据子宫收缩及胎儿排出情况可以考虑间隔2～3h重复使用1次.     

催产素在母猪繁殖中的利弊

催产素通用名缩宫素,无色澄明或几乎澄明液体,本品有兴奋子宫平滑肌,加强子宫收缩的作用,以妊娠后期尤其是临产母猪及刚分娩后更为敏感.     

使用催产素治疗母牛难产时的注意事项

催产素有兴奋子宫平滑肌 ,引起子宫的收缩从而发生分娩之作用。当母牛由于体内催产素的含量较低 ,子宫收缩微弱引起难产时 ,可用催产素催产 ,其中应注意的事项有 :1　催产素对子宫的收缩作用以临产及刚分娩后更为有效 ,无分娩预兆时用催产素无效。2　催产素主要作用于子宫体 ,对子宫颈的作用微弱。所以 ,子宫颈未张开或助产过迟子宫不再收缩 ,子宫颈已经缩小时 ,用催产素效果不理想。3　骨盆过狭、产道受阻、胎位不正等原因引起的难产以及有剖腹产史的母牛禁用 ,否则子宫剧烈收缩时可能发生破裂 ,所以在使用催产素前须先检查产道 ,胎位情况…     

浅谈宫缩素对母猪繁殖及胎儿的影响

缩宫素(催产素)有兴奋子宫平滑肌,引起子宫收缩而促进分娩的作用.当母猪由于体内催产素的含量低,子宫收缩微弱引起难产时,可用催产素催产.催产素的使用是有一定适应症的,不能滥用,也不能超剂量使用,如果使用不当,不仅催产不成,反而会造成胎儿窒息而死,母猪子宫破裂而亡,造成不必要的损失.     

催产素对兔子宫的促收缩作用的观察

催产素(Oxytocin),又名缩宫素,是垂体后叶素的主要成分。其催产素的主要生理作用是:能使子宫发生强烈收缩,排出胎儿;刺激乳腺泡上的肌上皮细胞收缩,使乳汁从腺泡中通过腺管进入乳池,发生放乳;     

羊分娩时正确使用缩宫素

正1缩宫素的作用缩宫素又叫催产素。它能选择性地兴奋子宫,加强子宫平滑肌的收缩。在妊娠早期,子宫处于孕激素环境中,对缩宫素不敏感。随着妊娠期的增加,雌激素浓度逐渐增加,子宫对缩宫素的敏感性逐渐增强,临产时达到高峰。缩宫素小剂量能增加妊娠后期子宫节律性收缩,较少引起子宫颈兴奋,适用于催产;剂量加大,能     

催产素的应用

催产素在产科应用较多,主要用于引产或催产。含量为1毫升含10毫克,能对子宫起收缩作用,应用时注意事项: 1.子宫颈口未开时采用催产素,易使子宫过早收缩,仔狐堵在宫颈内口处窒息死亡。     

母牛子宫脱出病例的诊治体会

母牛子宫脱出是一种常见多发产科疾病。按传统方法治疗由于子宫收缩复位不好,母牛继续努责易复发,且手术操作不便,疗效较差。本人在临床实践中根据催产素能使子宫收缩的原理,在整复手术前先宫壁注射催产素,然后再整复并配合其它疗法,取得     

缩宫素在养猪临床上的合理应用

缩宫素俗称催产素,是一种能选择性地兴奋子宫,加强子宫平滑肌收缩的药物。用药的剂量不同,能使子宫产生节律性收缩或强直性收缩。如果用量适当,子宫节律性收缩加强,促使胎儿迅     

Choriocarcinoma with metastasis in a rabbit (Oryctolagus cuniculi)

A 3-year-old female rabbit (Oryctolagus cuniculi) presented with apathy and indisposition for 2-3 days. Palpation revealed a mass in the caudal abdomen, namely, in the wall of the uterus. Ovariohysterectomy was performed, and the tissues were submitted for histopathologic examination. The mass consisted of 3 different (trophoblastic, syncytiotrophoblastic, and cytotrophoblastic) neoplastic cell types originating from the uterus. Immunohistochemistry was positive for cytokeratin in all 3 neoplastic cell types, and the syncytiotrophoblasts were positive also for human chorionic gonadotropin. Together these features allow the diagnosis choriocarcinoma. This report documents the first case of a spontaneous choriocarcinoma in a rabbit.     

Birth of calves after in vitro fertilisation using laparoscopy and rabbit oviduct incubation of zygotes

The infertility of many cows could be treated by in vitro fertilisation. In the present study laparoscopy was utilised to recover the in vivo matured oocytes from the ovary of a standing donor. After the capacitation of fresh semen with high ionic strength medium and in vitro fertilisation, a rabbit oviduct was employed as an incubator for four to five days, in order to obtain sufficiently aged embryos to be transferred to the uterus of a recipient. Using surgical or non-surgical transfer six calves were obtained.     

The normal microflora of the female rabbit''s genital tract.

Microorganisms associated with the vagina, cervix and uterus of rabbits were isolated and identified. The predominant microorganisms isolated from the vaginas and cervices were coagulase-negative staphylococci, micrococci, and nonfermentative bacilli. Coagulase-negative staphylococci were isolated frequently, but in small numbers, from the uteri. The pH of the rabbit vagina was found to be near neutrality. Our data indicate that the genital flora of female rabbits is relatively simple, regarding the number and type of microorganisms.     

Biomechanical analysis of 3 fixation techniques in rabbit radius and humerus bones

The objective of this study was to compare the strength and stiffness of various fixation methods applied to the long bones of the rabbit forelimb. Twenty rabbit radius/ulna and 20 rabbit humeri were randomly assigned to 1 of 4 groups. Control bones remained intact, whereas all others were osteotomized to create fracture models that were fixated with locking plate and locking screws (LP), veterinary cuttable plate (VCP) with cortical screws, or external skeletal fixator constructs (ESF), and tested in 4-point bending until failure. Load/deformation curves were generated for each sample and used to calculate stiffness (slope of the curve) and strength (load to failure). Intact controls had greater strength and stiffness than any fixation techniques in the rabbit radius/ulna and humeri samples. Locking plate and VCP constructs had greater stiffness than ESF when applied to the radius, whereas locking plate constructs were stronger than VCP or ESF when applied to the humerus. Overall, the LP construct had characteristics most closely resembling those of the intact control regarding strength in the humerus. Therefore, fracture fixation with a LP would provide the greatest strength in humeral fracture repairs in the rabbit.     

Bilateral Successive Cranial Cruciate Ligament Rupture Treated by Extracapsular Stabilization Surgery in a Pet Rabbit (Oryctolagus cuniculus)

A 4.1 kg, 4-month-old female pet rabbit was presented twice within a 4 month period for cranial cruciate ligament rupture of its right, then left stifle joint. Stifle joint stabilization was performed with an extracapsular technique after both events. Immediately after stabilization, the rabbit regained normal use of the injured limbs. The animal underwent a 3 month rehabilitation program intended to increase muscle strength. Twenty-four months after the procedures were performed the rabbit shows no signs of discomfort and has normal use of both rear legs.     

羊驼生殖器官的解剖与生殖生理学特性

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。     

东北虎雌性生殖系统解剖

对 2例 1 999年 1 0月意外死亡的东北虎雌性生殖系统进行了解剖。雌性东北虎的卵巢被覆卵巢囊 ,随着年龄增长卵巢表面凸凹不平 ,呈脑的沟回状。输卵管位于卵巢游离缘外侧 ,呈半圆形围绕着卵巢 ,输卵管壶腹部弯曲、峡部直 ;子宫与输卵管分界明显 ;子宫角长度约相当于子宫体长度的 2倍 ;阴道呈背腹压扁的管状     

A case of adenocarcinoma of the endometrium extending into the leiomyoma of the uterus in a rabbit

In a pet rabbit, 2 tumor masses one on each horn were macroscopically seen in the wall of the uterus. On light microscopic examination, the right horn mass consisted of an admixture of neoplastic epithelial and mesenchymal element. The epithelial element was composed of neoplastic epithelial cells with numerous mitotic figures and formed varied sizes of acini, glandular, and solid structures. The tumor was diagnosed as an adenocarcinoma of the endometrium. The mesenchymal element was composed of well-differentiated smooth muscle cells and was diagnosed as a leiomyoma. While adenocarcinoma cells formed a protrusive mass in the uterine lumen, they also showed an extension into the leiomyoma of the myometrium. By immunohistochemistry, adenocarcinoma stained positive for cytokeratin (MNF116) and leiomyoma stained positive for smooth muscle actin, showing a substantial difference in the cytological nature of these tumor cells. The results may give a further evidence supporting the narrative of the tumor development that an adenocarcinoma of the endometrium extended into leiomyoma of the uterus. To the author's knowledge, this is the first report describing this type of combination of two independent tumors in a pet rabbit.     

Regulation of uterine estrogen receptors (ER) by beta-adrenergic stimulation in immature rats

The effects of a 3-day intramuscular (i.m.) administration of clenbuterol (25 μ.g/ Kg), propranolol (12 mg/kg), clenbuterol (25 μg/kg) plus propranolol (12 mg/ Kg) and estradiol (0.5 μg) upon the female reproductive system were investigated in immature Sprague-Dawley rats. Clenbuterol and estradiol treatments induced a significant increase in uterus weight and in relative uterus weight, whereas in the groups treated with propranolol and clenbuterol plus propranolol no differences were detected versus controls. The uterine estrogen receptor levels were significantly increased by clenbuterol administration. In the rats dosed with propranolol and clenbuterol plus propranolol, no modifications occurred in estrogen receptor concentrations when compared with control values. Uterine progesterone receptors were never significantly affected by any of the considered treatments. Data obtained indicate that clenbuterol treatment induces an increase in uterus weight and in estrogen receptor levels and that these effects are regulated by acute beta-adrenergic stimulation, as the contemporaneous administration of high doses of a beta-blocker inhibit such effects.     

条件性子宫细胞剔除的研究

为了研究体内细胞的功能和各种细胞之间的相互作用,试验研究了可以特异性消除特定细胞的条件性细胞剔除新方法。通过PR^Cre/+工具鼠与pCAG-loxp-STOP-loxp-DTR-2A-EGFP转基因小鼠（DTR小鼠）交配获得子宫特异表达白喉毒素受体（DTR）的转基因小鼠,经过PCR和琼脂糖凝胶电泳鉴定基因后,筛选出PR^Cre/+/pCAG-loxp-STOP-loxp-DTR-2A-EGFP雌性小鼠（PR-DTR小鼠）。以DTR小鼠和野生型小鼠（WT小鼠）作为试验对照组,利用免疫组织化学和Western blotting检测子宫中绿色荧光蛋白（GFP）的表达。腹腔注射白喉毒素1 ng/d,连续2 d,观察PR-DTR小鼠、DTR小鼠和WT小鼠子宫的外部形态差异,并通过HE染色的方法观察子宫的内部形态。使用免疫组织化学方法检测注射白喉毒素后PR-DTR小鼠、DTR小鼠和WT小鼠子宫中叉头框蛋白A2（FOXA2）的表达。试验发现在小鼠子宫上皮、基质和肌层细胞中都有GFP的表达,注射白喉毒素后PR-DTR小鼠子宫红肿膨胀,DTR小鼠和WT小鼠子宫没有显著变化。HE染色试验结果发现,PR-DTR小鼠子宫中出现异常空腔,而DTR小鼠和WT小鼠子宫没有明显变化,并且对注射白喉毒素的PR-DTR小鼠子宫中FOXA2表达的检测结果表明,这些异常的空腔不属于腺体,说明白喉毒素使细胞死亡,证实在小鼠子宫中表达孕酮受体的细胞表达了DTR。试验结果表明,白喉毒素在PR-DTR小鼠子宫中可以条件性剔除子宫中表达孕酮受体的细胞,为研究子宫细胞的功能以及子宫细胞相互之间的作用提供了新方法。