Uterine Motility in Sows During Spontaneous Parturition and Induced Parturitions with the PGF Analog Alfbprostol and Oxytocin

Contents: Uterine activity, i.e. myometrial contractions, were recorded in 11 sows prior to and during parturition by using strain gauges placed onto uterine horns about 15 to 20 cm cranial of the bifurcation. Tocographic patterns observed prior to and during spontaneous and alfaprostol induced parturitions were normal. Administration of 20, 10 or 5 I.U. oxytocin 22 hours after alfaprostol quickly initiated abnormal periparturient contraction patterns with 20 and 10 I.U. oxytocin and in one of two animals receiving 5 I. U. These were characterized initially by prolonged tetanic contractions resulting in delayed deliveries, and later by the premature occurrence of patterns seen normally only during the phase of placental expulsions, although not all piglets had been delivered. The importance to use myornetrial activity profiles to evaluate parturition induction methods was stressed .     

奶生产后子宫感染与子宫疾病概述

奶牛子宫疾病是影响奶牛繁殖率,降低生产效益的重要因素之一.临床上奶牛子宫疾病的形成原因复杂,临床表现多样,同时又缺乏权威的诊断标准,给生产中临床诊断带来了很多困难.本文简要综述了子宫内细菌污染与子宫感染之间的关系,以及子宫疾病的病理学差异,概述了不同子宫疾病的临床表现和简单清晰的临床定义.     

奶牛产后子宫感染与子宫免疫

非特异性子宫感染会降低奶牛的生产性能和奶牛场的潜在效益。发生子宫感染时常并发感染化脓性放线杆菌或混合感染其他细菌。当从产后21 d的奶牛子宫液中分离到化脓性放线杆菌时,说明奶牛发生了严重的子宫内膜炎,并且将导致产后第一个发情期不孕。然而引起子宫感染的确切原因尚不清楚,但可以肯定与多种因素有关。发生难产、胎衣不下、怀有双胎或死胎以及患有各种代谢紊乱疾病的奶牛比其他奶牛更容易发生子宫感染。分娩前后异常的免疫功能更容易导致发生严重的子宫感染。子宫感染一般不会引起奶牛死亡,但是发生子宫感染的奶牛其生产性能会受到很大影响。另外,子宫发生感染还会降低产奶量,并且对子宫感染的一些治疗措施还会对牛奶产生污染。因为感染的非特异性,所以子宫感染很难预防;注意加强卫生设施以及围产期的卫生,特别是在助产过程中的卫生,才可能是最好的预防方法。异常免疫功能导致奶牛发生子宫感染的现象,说明通过对免疫功能的调节来预防和治疗围产期奶牛子宫感染是有潜力的。     

奶牛子宫组织内肥大细胞分布规律的研究

取4头奶牛的新鲜子宫,经生理盐水冲洗后,分别于子宫角、子宫颈和子宫体部位取材,放入10％中性福尔马林固定液中固定,对全层子宫进行连续切片,用甲苯胺蓝染色,再用油镜观察子宫内膜层、肌层和外膜层的肥大细胞数量。经生物统计分析发现,奶牛子宫组织内肥大细胞主要分布在子宫内膜层,在子宫肌层和外膜层较少;奶牛子宫各部位的内膜层、肌层和外膜层的肥大细胞构成比相近。     

Uterine Responses to Exogenous Oxytocin Before and After Pre-partum Luteolysis in the Cow

The aim of this study was to test the functional status of uterine oxytocin receptors in cows in vivo around parturition. The animals received consecutive, intra‐arterial injections of 800, 1600 and 3200 mU of oxytocin at three different stages: during late gestation (days 260–274), at 12 h and at 24 h after intramuscular injection of a prostaglandin F_2α analogue at day 275 to induce parturition. Cows (n=6) had been provided with myometrial electrodes and a catheter had been installed in the aorta and in a branch of the uterine vein (UV). Regular blood samples were obtained from the UV from 5 min before until 45 min after each oxytocin injection to measure plasma levels of prostaglandin F_2α (PGF_2α) and oxytocin. Uterine electromyographic (EMG) activity was registered continuously during each experiment. The increase of oxytocin levels in UV plasma after intra‐arterial injections was dose dependent (p < 0.02). Pre‐ and post treatment oxytocin levels at 24 h after induction of parturition were significantly increased (p=0.0313). Both during late pregnancy and at 12 h after induction of parturition, oxytocin caused a significant increase in EMG activity (p=0.022). After the 3200 mU dose the increase was significantly higher than with the other 2 doses (p=0.004). After each dose, EMG activity returned to baseline levels within some 15 min. At 24 h after induction of parturition, the pre‐treatment level of EMG activity had increased. Doses of 800 mU and 1600 mU of oxytocin produced a significant (p=0.022) increment of EMG activity, which was of the same magnitude as during the preceding stages; after 3200 mU of oxytocin the response was significantly higher than before (p=0.008). No significant increases of PGF_2α levels in UV plasma could be measured after oxytocin injections at any of the three stages. It is concluded that the myometrium of the pregnant cow responds in vivo to physiological doses of oxytocin. At 24 h after induction of parturition, when luteolysis has occurred and a parturient pattern of parturient myometrial activity has already started to develop, the response is enhanced. Physiological doses of oxytocin did not evoke a spurt release of PGF_2α in uterine venous blood during the peripartal period.     

奶牛子宫扭转的诊治

奶牛子宫扭转诊治的关键是早期诊断,选择最佳的治疗方法和及时救助,最大限度地确保母子的生命安全和母畜的繁殖力。     

奶牛产后子宫组织超微结构变化的研究

应用透射电镜观察两头奶牛产后第1、7、l3、20、26、32、38、45、52、60天的子宫组织的超微结构变化，结果发现：分娩使奶牛部分子宫内膜破损，并且与其相邻的细胞也在产后1～7d内坏死脱落；未破损上皮细胞的纤毛和微绒毛也受到损坏；产后第13天时，基底细胞开始生长以修复分娩时被损坏的子宫内膜，到45d时生长基本完成，产后60d时组织修复完成，纤毛和微绒毛覆盖整个子宫内膜表面。在产后1～7d内，子宫组织内胶原片段多、胶原纤维呈溶解状、横纹不清楚、胶原束内出现空腔；从产后第26天开始胶原纤维片段较少并排列较整齐，而第32天以后胶原纤维束交错整齐排列、横纹清楚、无胶原片段。在产后1～7d内，子宫平滑肌细胞核呈扭曲状、胞质内充满肌丝，并且体积较小；从产后20d开始平滑肌细胞体积增大、胞质内线粒体和高尔基复合体等细胞器增多。产后1～32d之间，子宫组织内巨噬细胞数量增多，其胞质内溶酶体、线粒体等细胞器增多；产后13～32d之间，浆细胞数量增多，其胞质内粗面内质网池扩大、线粒体和高尔基体等细胞器增多；淋巴细胞大量浸润。产后20～45d之间，成纤维细胞数量增加，其胞质内细胞器增多；产后7～45d之间毛细血管周围的周细胞数量增加。     

丹连花子宫灌注液治疗奶牛子宫内膜炎的实验性临床试验

为考察不同剂量的丹连花子宫灌注液对奶牛子宫内膜炎的临床治疗效果,选择患子宫内膜炎的患病奶牛50头,随机分为5组,每组10头,分别为丹连花子宫灌注液高、中、低剂量组,以及药物对照组和疾病对照组;另选健康奶牛10头作为健康对照。结果表明,丹连花子宫灌注液不同剂量组治疗后患病奶牛的临床症状明显改善,其中高、中剂量组奶牛子宫复旧完全,子宫颈黏液清亮,白细胞数明显减少,pH6.5~7.0,尿兰母检查阴性,治愈率60%,有效率90%,显著高于药物对照组(P<0.05),且血液白细胞数显著减少,其中中性粒细胞数极显著低于疾病对照组(P<0.01);不同剂量组血液生化指标无异常变化。表明丹连花子宫灌注液对奶牛子宫内膜炎有显著治疗效果,且使用安全,推荐临床使用剂量为100mL/次,子宫灌注给药,隔天1次,连用3次。     

助产对奶牛产后子宫菌群的影响

在奶牛养殖业中,难产是奶牛临床上的常发病,助产是处理难产的常用手段。助产的发生会导致母牛受胎率降低、冻精使用量增加、空怀时间增加和首次配种时间后移等繁殖问题。本研究从细菌学角度分析助产对奶牛产后子宫菌群的影响,以期为提高牧场受胎率提供数据参考。在宁夏地区某大型奶牛场,以助产和非助产奶牛为研究对象,在产后45 d进行子宫灌洗,采集灌洗液样本共7份。通过细菌分离培养、16S rRNA测序等方法分离细菌。结果共分离出10个细菌属,12种细菌,其中,非助产奶牛子宫冲洗液中分离出链霉菌属、链球菌属、肠杆菌属、葡萄球菌属、气球菌属5个属的细菌;助产奶牛子宫冲洗液分离出志贺菌属、不动杆菌属、假单胞菌属、棒状杆菌属、芽胞杆菌属、气球菌属、肠杆菌属、葡萄球菌属、链球菌属等9个属的细菌。本研究的结果表明,助产和非助产奶牛子宫菌群差异显著,助产导致子宫内菌群多样性增加。     

Uterine Vascular Perfusion and Involution During the Postpartum Period in Mares

In horses, limited data is found regarding the vascular events during uterine involution at the puerperal period. Thus, we aimed to evaluate the morphological aspects (size of uterus and intrauterine fluid content) and the hemodynamics (endometrial and mesometrial vascular perfusion) of the uterus during its postpartum involution process. Ten mares were daily scanned by transrectal color Doppler ultrasonography from the first day postpartum (d1) to the 16th day after first postpartum ovulation (D0 = ovulation). The formerly gravid horn (GH) and formerly nongravid horn (NH) were individually evaluated. A reduction (P < .05) in the uterine diameter was observed during the first 7 days postpartum, and the rate of uterine involution decreased after this period. The involution was completed on d21 and d24 for the NH and GH, respectively. Presence of intrauterine fluid was present in large amounts between d1 and d2 postpartum, followed by a decrease (P < .05) between d4 and d7. No fluid was observed after d16 postpartum or after the third day postovulation (D3). During the early postpartum period, an increase (P < .05) in the endometrial and mesometrial vascularization was detected, respectively, between d1 and d4, and between d1 and d2. The vascular perfusion did not differ after d4 for endometrial tissue, whereas was reduced (P < .05) between d2 and d10 for mesometrium. After the first postpartum ovulation, an increase (P < .05) in vascular perfusion was observed from D0 to D5, followed by a decrease (P < .05) between D5 and D11 and an increase (P < .05) between D11 and D14. The novel vascular perfusion profile here described in the endometrium and mesometrium after ovulation is similar to the uterine vascular profile observed during estrous cycles and early pregnancy, indicating a fast return of the mare's uterus to cycling postpartum conditions.     

交巢穴埋线和注射催产素对奶牛产后子宫复旧影响的比较

为了比较奶牛交巢穴埋线与注射催产素对子宫复旧的影响,本试验共选取了20头荷斯坦牛,10头作为试验组1,分娩后在其交巢穴埋线;10头作为试验组2,分娩后在交巢穴注射催产素。观察奶牛的胎衣、恶露排出及子宫复旧情况,发现两种方法对胎衣排出时间的影响差异不显著,而埋线处理对子宫复旧较注射催产素有明显的促进作用,     

围产期饲喂β-胡萝卜素对奶牛免疫性能的影响

试验选择胎次相同、产奶量、体重和体况相近的中国荷斯坦奶牛36头,随机分为3组,分别饲喂对照日粮(基础日粮+150 000 IU维生素A),处理Ⅰ日粮(对照日粮+300 mg-β胡萝卜素),处理Ⅱ日粮(对照日粮+600 mg-β胡萝卜素),预试期15 d,试验期120 d。结果表明:添加-β胡萝卜素对奶牛血液白细胞数量和白细胞分类计数没有显著影响,但提高了围产期奶牛血液淋巴细胞的转化率(P<0.01)。-β胡萝卜素的添加提高了血浆中-β胡萝卜素和维生素A的浓度;在产后8-12周,处理组奶中-β胡萝卜素的浓度显著提高(P<0.005),而且奶中-β胡萝卜素的浓度随着-β胡萝卜素添加量的增加而上升,但-β胡萝卜素的添加对产后4周内奶中的-β胡萝卜素的浓度没有影响。     

奶牛性控冻精和常规冻精活力对比试验分析

试验观测对比奶牛性控冻精和常规冻精解冻后精子存活时间,为进一步把握输精时间,提高受胎率提供依据。试验结果表明:性控冻精刚解冻时活力较高,为0.5级以上,但活力下降快、存活时间较短,解冻后6h活力降低为零;常规冻精刚解冻时活力在0.4～0.5级之间,但存活时间较长,活力下降速度慢,解冻后8h活力降低为零。所以性控冻精解冻后,要求输精技术员尽快输精。     

Uterine Expression of Epidermal Growth Factor Family During the Course of Pregnancy in Pigs

To stably maintain pregnancy, several genes are expressed in the uterus. In particular, the endometrial expression of genes encoding growth factors appears to play a key role in maternal–foetal communication. The previous studies characterized the endometrial expression kinetics of the genes encoding epidermal growth factor (EGF), its receptor (EGFR), transforming growth factor-alpha (TGF-α), amphiregulin (Areg), heparin-binding (Hb) EGF and calbindin-D9k (CaBP-9k) in pigs during implantation. Here, we further characterized the expression patterns of these molecules during the entire porcine pregnancy. Porcine uteri were collected at pregnancy days (PD) 12, 15, 30, 60, 90 and 110 and subjected to RT-PCR. EGF and EGFR showed similar expression patterns, being highly expressed around implantation and then disappearing. TGF-α and Areg expression levels rose steadily until they peaked at PD30, after which they gradually decreased to PD12 levels. This Areg mRNA expression pattern was confirmed by real-time PCR and similar Areg protein expression patterns were observed. Immunohistochemical analysis of PD60 uteri revealed Areg in the glandular and luminal epithelial cells. Hb EGF was steadily expressed throughout the entire pregnancy, while CaBP-9k was expressed strongly on PD12, and then declined sharply on PD15 before recovering slightly for the remainder of the pregnancy. Thus, the EGF family may play a key role during implantation in pigs. In addition, CaBP-9k may help to maintain uterine quiescence during pregnancy by sequestering cytoplasmic Ca²⁺.