不同黄体大小对受体妊娠率的影响

比较了受体母牛不同黄体大小对胚胎移植后妊娠率的影响。具有0.8cm黄体的受体母牛,与具有1cm和1.2cm黄体的受体母牛,胚胎移植后的妊娠率差异不显著(P0.05)(50.0%,48.1%和49.78%)。具有1.5cm和1.8～2.0cm以上黄体的受体母牛,妊娠率明显较高(55.08%和57.89%),但只占总受体数的15.09%。结论:受体母牛子宫正常,具有0.8cm以上质地良好的黄体,均适合进行胚胎移植。     

提高波尔山羊超排效果及移植妊娠率研究初报

以波尔山羊为供体、本地白山羊及其用萨能奶山羊改良的高代杂种羊为受体,开展提高超排效果及移植妊娠率研究。结果表明:在提高超排效果研究方面,注射P4+LRH-A3组较对照组头均获胚胎数及可用胚胎的百分率分别提高5.4枚和17.7％;注射P4组、注射LRH-A3组较对照组头均获可用胚胎的百分率分别提高18.99％和14.87％。在提高受体移植妊娠率研究方面,移单胚、双胚、三胚的受体羊移植妊娠率组间差异不显著,但移三胚的受体羊产羔率较移单胚、双胚分别提高66.92％和36.09％,差异极显著;受体羊移入胚胎发育阶段相同的1枚或2枚同等级胚胎(A级或B级),妊娠率和产羔率无显著影响,但移入2枚A级囊胚受体羊的产羔率较移入2枚A级桑椹胚的产羔率高36.23％,差异显著;移植受体的一侧卵巢上有3个以上黄体的妊娠率显著高于1个黄体和2个黄体,分别高31.55％和29.23％,差异显著。移入胚胎的受体羊卵巢上黄体和卵泡同时存在,将卵泡刺破使卵泡液流失,与卵巢上只有黄体存在的受体羊移植妊娠率无显著差异;向子宫角方向和逆子宫角方向移植胚胎对受体羊移植妊娠率无显著差异。     

荷斯坦青年牛超排影响因素分析及效果比较

对105头荷斯坦奶牛进行超数排卵处理,对超排取得2个以上黄体的89头母牛进行采卵,其中12~14月龄青年牛39头和成母牛50头。超排结果表明,15月龄以下青年奶牛经FSH-PG方案超排可以取得良好的胚胎生产效果,可用胚率达到51.2%,头次超排获得可用胚5.33±3.90枚。试验还表明,超排时月龄、体重、FSH注射剂量、超排前黄体质量等因素能影响超排结果。16头供体奶牛采卵后经回移胚胎,受胎率较低;PG处理了51头供体奶牛,返情率为68.6%。     

和牛母牛超数排卵及胚胎移植试验研究效果初报

[目的]研究和牛母牛超数排卵及胚胎移植效果。[方法]利用纯种和牛母牛作为供体,荷斯坦母牛及西杂母牛作为受体,通过供体牛的超数排卵、人工授精、采胚、胚胎冷冻及受体牛的同期发情和鲜胚移植,快速获得纯种和牛及和牛胚胎。[结果]对4头青年纯种和牛母牛进行超排,重复冲卵13头次,共采卵数122枚,其中75枚可用胚胎,可用胚率为61.5%,平均5.76枚/头次。对75头荷斯坦牛及西杂母牛同期发情,结果获得89.2%的同期发情率。67头受体牛移植了鲜胚,2个月后妊娠检查有35头怀孕,移植妊娠率为52.23%。[结论]可以利用超数排卵及胚胎移植增加和牛母牛利用效率。     

牛胚胎移植技术在中国内蒙古的研究和应用

1991－1996年，对6个品种138头供体母牛超排处理199次，共获得A、B级胚胎1148枚，平均每次每头获可用胚5．77枚；共移植受体1299头（包括鲜胚和冻胚），妊娠产犊593头，总移植妊娠率为45．7％。对牛的超数排卵技术进行了深入研究，对不同超排方法的超排效果、不同品种肉牛的超排反应及重复超排的效果进行了分析，获得了适于重复应用、效果稳定的超排方案，邓用FSH－PG法，FSH总剂量在4－6mg,5d 10次递减注射。同时，对受体牛饲养管理条件与受体诱导同期发情效果和移植妊娠率之间的关系进行了探讨，对经产牛和育成牛受本移植妊娠效果进行了比较，并对移植人员技术熟练程度对妊娠率的影响进行了分析，从而为大规模实施牛ET计划提供了受体牛选择依据。     

娟姗牛与荷斯坦青年母牛超排效果比较

本试验对56头娟姗牛与179头荷斯坦青年母牛进行超排处理,分别获得可用胚胎227枚和1242枚;可用胚率分别为57.80%和70.65%,娟姗牛和荷斯坦牛超排黄体数无明显差异(P>0.05),但采胚数明显低于荷斯坦牛,娟姗牛的超排结果明显低于荷斯坦牛的结果(P<0.05),移植受体牛270头,怀孕157头。移植妊娠率分别达到52.54%和50.20%,同期娟姗牛胚胎与荷斯坦牛胚胎移植结果比较,无显著差异(P>0.05)。娟姗牛超排使用FSH剂量为9mg更为经济。青年荷斯坦牛和娟姗牛可用于胚胎生产,但青年娟姗牛的可用胚胎数低于荷斯坦牛。     

奶牛胚胎形态学观察与移植妊娠率的关系

在牛胚胎移植中,超数排卵是增加胚胎数量的有效手段,但在一定程度上影响着胚胎的质量和结构;胚胎质量的好坏,直接影响着受体母牛的移植妊娠率。为充分有效地利用受体母牛,提高妊娠率,在移植前对胚胎质量进行评价很有必要。本试验是将超排采得的奶牛胚胎,在实体显微镜下肉眼进行形态学观察,按照胚胎的形态进行鉴定和分     

荷斯坦青年母牛超排前卵巢状况对超排效果的影响

对1035头荷斯坦青年母牛的超排效果进行了分析统计。将超排前卵巢状况有记录的669头供体,分成7组;检查卵巢但没有记录的366头供体作为对照。对比7组之间超排效果,‘L+’组的超排效果最好,与其他组比较,差异显著(P0.05)。除‘L+’组外,在其他各组中,胚胎有效率的差异不显著(P0.05)。因此,在选择供体母牛用作超排时,特别是用性控精液配种的供体母牛,可以选用一侧卵巢有黄体,另一侧卵巢有活性的供体母牛。从而进一步提高有效胚胎率和降低成本。     

牛胚胎移植技术在旺苍县的应用试验

为探究肉牛胚胎移植技术在旺苍县的应用前景,本试验组建了 83头西杂母牛开展同期发情,对筛选的34头受体母牛进行西门塔尔牛冷冻胚胎移植.结果得出:旺苍县西杂母牛的同期发情率为75.90％,胚胎移植妊娠率为38.24％;体况评分在6～6.5分时妊娠率最高(为42.86％),具有1.5 cm及以上黄体的受体母牛,其妊娠率也较...     

推广胚胎移植应注意的问题

1根据饲养规模选择适宜的移植方式对于有一定规模的畜场或受体群的数量能够达到要求的,可采用成功率较高的鲜胚移植,但所需成本较高。因为要根据受体群大小,选择合适的供体数量,供体超排,受体同期发情处理,超排后冲胚,所得的新鲜胚胎用于移植。对有些家畜分布较散,数量又少,应在自然发情后随时移植冷冻胚胎,该法依靠受体自然发情,免去了发情处理中药品、交通等的费用,降低了成本,适于农村条件下的低成本推广。2应保证胚胎的质量胚胎的质量直接影响移植妊娠率,以A、B级胚胎进行移植可获得较高的妊娠率。对于进口或超排所得的胚胎,应做好胚胎…     

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。     

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。     

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。     

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。     

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。     

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.