胎衣不下奶牛分娩前后血浆PGE2水平变化

采用放射性免疫测定法，探讨了胎衣不下奶牛分娩前后血浆中前列腺素PGE2水平的变化。结果发现正常分娩的奶牛PGE2的量从分娩前4d开始上升直到分娩前2d达最高，分娩前1d又降到最低，分娩时与分娩后略有回升，而胎衣不下奶牛PGE2的量分分娩前4d开始下降，到分娩前2d降到最低，分娩前1d突然升达最高值，分娩时和分娩后与正常分娩的奶牛PGE2的量持平，这揭示正常分娩和胎衣不下奶牛的PGE2量和时相差异可引起免疫失调，造成奶牛胎衣不下。     

奶牛胎衣不下的病因及防治措施

奶牛胎衣不下是指奶牛在正常分娩或非正常分娩后12h内胎衣不能自然脱落.健康奶牛在正常分娩后胎衣不下的发病率约为3~12%,异常分娩的奶牛,如双胎、难产、流产、早产以及感染布病的牛群,胎衣不下的发病率为20~50%,发生过胎衣不下的牛,其代谢性疾病、乳腺炎、子宫炎和以后发生流产的发病率更高.     

产后1周胎衣不下奶牛子宫内膜TLR2、TLR4和CD14的mRNA表达变化

为了探讨奶牛胎衣不下对子宫内膜先天免疫相关基因表达的影响,在产后第1天和第7天,对9头胎衣不下的奶牛和10头正常分娩的奶牛进行子宫内膜活检;每周收集子宫内容物进行需氧菌分离培养;在产后第1天和第7天,检测所有奶牛子宫内膜TLR1/6、TLR2、TLR4、TLR5、TLR9、NOD1、NOD2、CD14和MD2的基因表达。结果表明:无论奶牛有无胎衣不下,在产后21 d内大肠杆菌是子宫内容物中最常见的细菌;产后第7天与第1天相比,胎衣不下的奶牛子宫内膜TLR2、TLR4和CD14的基因表达水平明显降低(P0.05),而正常分娩的奶牛在相同时间段上述受体基因表达无明显差异,说明产后1周胎衣不下的奶牛子宫内膜TLR2、TLR4和CD14的基因表达减少可能与子宫感染炎症有关。     

规模化奶牛场奶牛胎衣不下原因探究

近几年,规模化万头牧场全面兴起,单产不断提升,然而奶牛胎衣不下常有发生,本文旨在查明分娩奶牛胎衣不下的发病原因及规律,为防治奶牛胎衣不下制定有效的综合防治措施提供数据参考。本研究通过流行病学调查,对2022年11月—2023年10月一年间分娩的2 936头荷斯坦奶牛从分娩胎次、胎儿性别、单双胎、胎儿出生体重、产犊难易度等生产实际状况进行调查与统计,分析其与分娩母牛胎衣不下的关系。结果显示,二胎次奶牛产后胎衣不下的发病率最低,初次分娩的奶牛产后胎衣不下发病率高达24.41%,发病率最高;产公犊的奶牛胎衣不下发病率显著高于产母犊的奶牛（P<0.05）;产双胞胎的奶牛胎衣不下发病率显著高于产单胎的奶牛（P<0.05）;犊牛初生重<30kg时,奶牛胎衣不下发病率高于其他体重群体;在胎天数<260d的分娩奶牛胎衣不下发病率显著高于其他分娩奶牛（P<0.05）;自然分娩奶牛胎衣不下发病率显著低于助产奶牛（P<0.05）。综上,分娩胎次为二胎时,奶牛胎衣不下发病率最低,头胎发病率最高;产公牛犊,母畜怀有双胎,胎儿出生体重<30 kg、>36 kg,早产...     

影响奶牛胎衣不下的因素

奶牛分娩后,胎衣在12h内不能自然脱落,称为胎衣不下。一般胎衣不下的发病率可达10%～30%,而正常分娩的奶牛,胎衣不下的发病率为     

奶牛胎衣不下的原因及防治方法

奶牛分娩后,胎衣在12h内不能自行完全脱落者,即称胎衣不下,又称胞衣不下,胎盘滞留.正常分娩的奶牛,胎衣不下的发病率为3%～10%,异常分娩,如双胎、流产、难产,发病率可高达30%～45%;奶牛的胎衣不下常会引起子宫内膜炎,导致久配不孕或发情推迟,产奶量下降.     

浅谈奶牛胎衣不下的治疗(RFM)

奶牛胎衣不下指奶牛分娩后，胎衣在12个小时内不能自然脱落，称胎衣不下(Retained Fetal Membranes．RFM)。它是奶牛常见的产科疾病之一，在无布氏杆菌病流行的地区，正常分娩后胎衣不下的发病率约为3％～12％，平均为7％；在异常分娩的母牛和患布氏杆菌病的牛群中，胎衣不下的发病率为、30％，甚至更高。对该病     

奶牛胎衣不下的病因分析及防治措施

正胎衣不下是指奶牛分娩后12小时内胎衣未能完全自然排出的症状。无布病地区,健康奶牛在正常分娩后胎衣不下的发病率约为3%~12%,平均为7%;异常分娩的奶牛,如双胎、难产、流产、早产以及感染布病的牛群,胎衣不下的发病率为20%~50%,甚至更高。胎衣不下不但能引起产奶量下降,还可引起子宫内膜炎症和子宫复旧延迟,从而导致不孕,致使许多     

浅议奶牛胎衣不下的综合防治措施

牛产犊后,胎衣不下在兽医临床上较多见,一般第3胎次以上奶牛较易发生.健康奶牛正常分娩后胎衣不下的发病率为3%～12%,异常分娩后的奶牛如难产、流产、早产、胎儿过大、胎水过多以及感染布氏杆菌病的牛群,其发病率占分娩母牛的20%～50%,甚至更高.胎衣不下的母牛80%以上可继发子宫内膜炎,导致奶牛体弱、消瘦、产奶量下降、产后发情延迟、受胎率降低,甚至造成奶牛不孕,最终被淘汰.因此预防和治疗奶牛胎衣不下是各养牛户亟待解决的问题.笔者根据阅读各方面的有关资料和多年的临床经验,浅议奶牛胎衣不下的综合防治措施.……     

提高群体奶牛健康水平的几项工作

1及时治疗胎衣不下胎衣不下不但易引起产奶量下降,还可以引起子宫炎和子宫复旧延迟,从而导致奶牛不孕,致使许多奶牛被迫提前淘汰。因此对奶牛场造成极大损失。据报道,正常分娩的健康奶牛,胎衣不下发病率为7%(±4%)左右,异常分娩的母牛,如双胎、难产、流产、早产以及感染布氏杆菌病的牛群,发病率为     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

商会自治的基石——商会自治规范研究

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。     

猪毛色遗传的研究进展

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。     

中华人民共和国农业部公告 第267号

为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …     

鸡败血支原体垂直传播模式及其阻断方法

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。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

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.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分（表面蛋白、脂磷壁酸和肽聚糖）与肠道受体（Ｃ型凝集素受体、Ｔｏｌｌ样受体和 Ｎｏｄ样受体）,阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。     

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.