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1.
对进口的加拿大牛冻胚胎进行解冻后移植效果观察。结果共解冻24枚冻胚,解冻后直接移植给24头受体牛,妊娠19头,移植妊娠率79.2%,其中荷斯坦奶牛冻胚移植21头,妊娠17头,移植妊娠率达81.0%,创造我国牛冷冻胚胎移植成功率的最高记录。  相似文献   

2.
本地黄牛冷冻胚胎移植技术及其受胎率影响因素分析   总被引:3,自引:2,他引:1  
笔者选用97头山东省平度市当地黄牛作为受体,采用玻璃化解冻进行加拿大进口北美性控高产荷斯坦奶牛冷冻胚胎移植。试验分别从冷冻胚胎级别、受体牛黄体直径、移植者技术水平、胚胎解冻后的停留时间,对冷冻胚胎移植受胎率进行了分析比较。结果表明:A级胚胎(46.3%)比B级胚胎(31.6%)、C级胚胎(0)受胎率高;受体牛黄体直径在1.0~1.5cm(49.1%)之间较2cm(28.1%)、2.5cm时受胎率要高;移植者技术水平的高(42.3%)低(21.1%)其受胎率相差较大;胚胎解冻后停留的时间10~20min(37.8%)、1~2h(46.9%)、4~6h(25%)对受胎率也影响较大。说明影响当地黄牛移植高产荷斯坦奶牛冷冻胚胎受胎率的因素主要有冷冻胚胎级别、受体牛黄体直径、移植者技术水平、胚胎解冻后停留的时间。  相似文献   

3.
用简易分割方法,分割奶牛冷冻胚胎16枚,获得半胚32枚,分割成功率为100%(16/16),可移植半胚29枚,移植于16头受体牛,到第3个情期未返情者经直肠检查有6头妊娠,妊娠率为37.5%(6/16)。其中,在分割前或者分割后经恢复培养0.5~2h再移植的10头受体牛,5头妊娠;而未经恢复培养,分割后直接移植的6头受体牛中,只有1头妊娠。移植后3个月,直肠检查确定2头流产。已有1头受体黄牛生出1头奶牛牛犊(母)和1头受体奶牛产1头奶牛牛犊。其余的2头妊娠受体牛将于9月份产犊。此外,用简易分割法分割奶牛胚胎5枚,得到半胚10枚,裸半胚直接冷冻,解冻后回收可移植半胚5枚,移植于4头受体牛,无一头妊娠。结果表明,冷冻胚胎的分割半胚优于分割后冷冻半胚移植效果;冷冻胚胎分割前或者分割后恢复培养移植优于未经恢复培养而直接移植;简易分割法可应用于冷冻胚胎的分割。  相似文献   

4.
通过对进口的加拿大荷斯坦牛试管冷冻胚胎进行解冻后移植黄牛的试验观察,结果共解冻60枚试管牛冻胚,经形态学鉴定符合移植标准者共44枚,可移植胚胎比率为73.3%,移植黄牛受体44头,妊娠20头,移植妊娠率为45.5%。天津市首批试管牛犊于2002年9月间相继诞生4头。试验结果表明,利用试管牛胚胎移植技术,借黄牛之腹直接生产纯种奶牛是一项促进奶牛业快速发展的有效技术途径。  相似文献   

5.
奶牛胚胎移植技术目前已经做为一项常规繁殖技术在生产中推广应用,但是白城地区还没有在生产上得到应用。为了探讨该项技术在白城地区应用的可行性。白城市兴牧胚胎生物工程有限责任公司进行了奶牛胚胎移植技术试验示范,利用当地改良牛做受体,移植加拿大高产奶牛胚胎。2004年共进行4批移植,移植受体牛174头次,受胎79头,总受胎率45.4%。其中最高受胎率57.89%,最低受胎率17.86%。现将结果报告如下。  相似文献   

6.
对进口的加拿大牛冷冻胚胎进行解冻后移植效果观察.结果共解冻24枚冻胚,解冻后直接移植给24头受体牛,妊娠19头,移植妊娠率79.2%,其中荷斯坦奶牛冻胚移植21头,妊娠17头,移植妊娠率达81.0%,创造我国牛冷冻胚胎移植成功率的最高记录.  相似文献   

7.
我州首次用41头在农村饲养条件下的荷邓杂交奶牛作为受体,移植了41枚体外成熟培养的冷冻胚胎。结果,有1头受胎,受胎率2.4%,说明移植成功,但有必要进一步探索提高。  相似文献   

8.
我们对牛胚胎快速冷冻技术进行了研究。1992年8月一11月间在木兰县,共移植受体母牛99头,有46头受体母牛妊娠,妊娠率为46.5%,有29头受体牛产犊,产犊率为29.3%。通过研究得知,牛胚胎快速冷冻技术可以应用于生产。  相似文献   

9.
2002-2004年,从饲养的812头奶牛群中,选择69头高产奶牛作供体进行超数排卵处理,63头供体牛共获胚胎495枚,超排成功率达91.3%(63/69),平均获胚胎7.17枚/头,可用胚胎402枚,平均可用胚胎5.82枚。其中采用加拿大生产的促卵泡素超排处理奶牛供体10头,获卵106枚,可用胚胎87枚,平均获可用胚胎8.7枚/头;采用鲜胚移植奶牛受体8l头,妊娠44头,妊娠率为54.3%,产犊28头,待产16头;采用冷冻胚胎移植黄牛受体278头,妊娠114头,妊娠率为41.0%。产犊22头,待产92头。  相似文献   

10.
引进上海高产黑白花奶牛冷冻胚胎,在贵阳三联乳业有限公司奶牛场进行胚胎移植。试验分3次进行,黑白花受体牛56头。结果妊娠2l头,平均妊娠率37.50%;其中第3次移植29头,妊娠14头,移植妊娠率48.28%。  相似文献   

11.
12.
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。  相似文献   

13.
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。  相似文献   

14.
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。  相似文献   

15.
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.  相似文献   

16.
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。  相似文献   

17.
乳酸杆菌益生作用机制的研究进展   总被引:2,自引:0,他引:2  
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。  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis.  相似文献   

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