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1.
兔胚胎核移植操作条件的建立   总被引：1，自引：0，他引：1  
本文对影响家兔胚胎细胞核移植的几个重要因素进行了研究。以不同的融合电场强度对重组胚进行处理，结果表明脉冲参数为１．６５ｋｖ／ｃｍ，脉宽为８５μｓ，脉冲数为１时，融合率达到７７．１％。显著高于其它场强的融合率。当场强增加至２．５０ｋｖ／ｃｍ时，多数重组胚发生溶解。融合液中的离子成份对重组胚的激活有重要影响。以０．３Ｍ甘露醇为融合液时，电激三次的激活率（５０％）显著高于一次（３６％）和二次（２２．２％Ｐ＜０．０５）。当加入１００μｎＣａ２＋时，电激三次后的激活率达到７１．４％，显著高于电激一次（４８％，Ｐ＜０．０１）和二次（６１．３％，Ｐ＜０．０５）。多次电激还可提高重组胚的发育率，当有Ｃａ２＋存在时，三次电激后的囊胚发育率为３１．４％。此外，随着卵母细胞卵龄的增加，重组胚的囊胚发育率下降，而融合胚的碎裂率则增高。当卵龄为ＨＣＧ后２１—２４小时，碎裂率高达５２％。对８－，１６－，３２－细胞期卵裂球的重组胚体外发育能力的研究表明，８－细胞期卵裂球的重组胚之囊胚发育率显著高于１６－及３２－细胞期卵裂的重组胚（３６．４％比２６％、２７．５％，Ｐ＜０．０５）。将部分３２－细胞期卵裂球的重组胚移入受体后，产出了３只核移植  相似文献   

2.
显微注射Ca^2＋激活小鼠M Ⅱ期卵母细胞   总被引：2，自引：0，他引：2  
胞质内显微注入Ｃａ＾２＋可以激活小鼠Ｍ Ⅱ期卵母细胞，且随着卵龄的增加，激活率明显升高。卵龄小于１６ｈ（ｈＣＧ注射后）注射Ｃａ＾２＋引起的激活率很低，卵龄超过１８ｈ，激活率达到５０％以上。卵龄小于１６ｈ的卵母细胞，卵内注入超纯水未能激活卵母细胞，而在１８￣１９ｈ卵龄组，注射水的对照组激活率为３５％，但显著或极显著地低于注射Ｃａ＾２＋的试验组。激活前注射ＥＤＴＡ卵母细胞的激活率约为３０％，激活后注射  相似文献   

3.
兔核移植胚胎的克隆研究   总被引：12，自引：0，他引：12  
本研究改进了兔受体卵母细胞的去核程序及供体卵裂球的处理方法，并对核移植胚的体外克隆、继代克隆及克隆胚的体内发育进行了试验。结果表明：卵龄对受体卵母细胞的去核具有显著的影响，卵龄为１５～１８ｈ的去核率为１００％（４５／４５），显著高于１３～１４ｈ的４６．６％（７／１５），Ｐ＜０．０１。ＤＮＡ合成抑制剂Ａｐｈｉｄｉｃｏｌｉｎ处理１６－细胞期卵裂球后，重组胚的囊胚发育率５４％（２０／３７）高于未处理组的４５％（１４／３１），Ｐ＜０．０５。从２枚１６－细胞供体胚分别获得来自一个供体胚的９枚和７枚核移植克隆囊胚，囊胚发育率为５１．６（１６／３１）。然而第一次继代核移植胚的囊胚发育率仅为１１．５％（６／５２）。１６－及３２－细胞期卵裂球的重组胚可发育至产仔，共获２窝８只仔兔。其中１只、２只、２只和３只仔兔分别来自４个供体胚。  相似文献   

4.
采用瘘管手术方法对３头生长牦牛在饲喂代谢能ＭＥ均为９．６ＭＪ／ｋｇＤＭ，粗蛋白（ＣＰ）为８％和１２％的日粮时的复胃氮代谢与瘤胃、肠道消化代谢进行研究。试验结果表明，日粮ＣＰ水平升高后，生长牦牛瘤胃氨氮浓度由３．３升至５．９ｍｇ／１００ｍｌ（Ｐ＜０．０１），瘤胃内氮的消失率由１．９％升到２１．１％（Ｐ＜０．０１）。瘤胃微生物蛋白质合成效率基本不变（平均６９．１ｇＣｐ／ｋｇＤＯＭ）；一昼夜进入十二指肠的食糜量及食糜干物质量基本不变；食糜总氮、氨氮及非氨氮量均显著增加（Ｐ＜０．０１），其中非氨氮增加２０％：非氨氮中微生物氮的比例由４５％降至３９％（Ｐ＜０，０５）；日粮ＤＭ，ＯＭ，ＣＰ和ＡＤＦ整体消化率分别提高１２．９％、１３．４％、３４％和２２．３％（Ｐ＜０．０１）。日粮ＣＰ由８％升至１２％后，生长牦牛瘤胃ＴＶＦＡ中乙酸比例由５４％降至４３．５％（Ｐ＜０．０１）．丙酸比例由２４．８％升至２８．４％（Ｐ＜０．０５），丁酸比例也由２１．１％增至２８．５％（Ｐ＜０．０１）。同时Ｃ２／Ｃ３比由２．１９降至１．５４（Ｐ＜０．０１）。  相似文献   

5.
克伦特罗在猪体内的生物利用度及药物动力学研究   总被引：20，自引：1，他引：19  
６头体重４７．００±４．５７ｋｇ（Ｘ±Ｓ）的健康长白和大白杂交猪，拉丁方设计试验，按４ｍｇ／ｋｇ静注、肌注和内服克伦特罗，高效液相色谱法检测血浆中药物浓度，ＭＣＰＫＰ药代动力学程序处理药时数据。静注给药的药代动力学参数是：ｔ１／２α０．６２±０．１２ｈ，ｔ１／２β４．８７±１．５６ｈ，Ｖｄ（ａｒｅａ）４．４８±０．５６ｌ／ｋｇ，ＣｌＢ０．６３±０．１１ｌ／ｋｇ／ｈ，ＡＵＣ６．３９±１．２７μｇ／ｍｌ．ｈ。肌注给药的药动学参数是：ｔ１／２Ｋａ０．２２±０．１０ｈ，ｔ１／２α０．５６±０．２１ｈ，ｔ１／２β４．２５±１．１０ｈ，ｔｍａｘ０．６０±０．１３ｈ，Ｃｍａｘ１．２７±０．３５μｇ／ｍｌ，ＡＵＣ５．４８±１．２９μｇ／ｍｌ．ｈ，Ｆ８５．４０±４．６９％。内服给药的药动学参数是：ｔ１／２Ｋａ０．２８±０．１５ｈ，ｔ１／２Ｋｅ３．１５±０．３６ｈ，ｔｍａｘ１．４６±０．１９ｈ，Ｃｍａｘ０．６５±０．１３μｇ／ｍｌ，ＡＵＣ３．９３±０．９９ｍｇ／ｌ．ｈ，Ｆ６１．０２±１０．９０％。肌注给药的生物利用度与内服比较，差异极显著（Ｐ＜０．０１）。  相似文献   

6.
犬卵母细胞体外成熟的影响因素   总被引：8，自引：0，他引：8  
采集发情期和间情期犬卵巢,回收大腔（直径大于１ｍｍ）卵泡和不可见卵泡的卵母细胞,在４种成熟液（ＴＣＭ１９９＋２０％ＦＣＳ,ＴＣＭ１９９＋２０％ＦＣＳ＋１０ＩＵ／ｍＬＦＳＨ,ＴＣＭ１９９＋２０％ＥＤＳ和ＴＣＭ１９９＋２０％ＥＤＳ＋１０ＩＵ／ｍＬＦＳＨ）中成熟后进行了受精试验。结果：（１）发情期大于２ｍｍ和１～２ｍｍ的大腔卵泡卵母细胞的体外成熟率（４２．５％,３２．５％）显著高于间情期卵母细胞（２０．４％）,但发情犬不可见卵泡卵母细胞的体外成熟率（２８．９％）与间情期卵母细胞差异不显著;（２）在成熟液中添加促性腺激素,能有效地提高卵母细胞成熟率,不可见卵泡的卵母细胞对促性腺激素的依赖性（３０．０％比７．８％）大于大腔卵泡的卵母细胞（４２．５％比２９．０％）;（３）卵丘扩散与卵母细胞成熟存在相关性;（４）ＥＤＳ可诱导卵丘扩散,但不能有效提高卵母细胞的成熟率;（５）发情期卵巢上的大腔卵泡和不可见卵泡的卵母细胞以及间情期卵巢不可见卵泡的卵母细胞体外培养后,与体外获能的精子进行体外受精,其卵裂率分别为１６．０％（４／２５）,０％（０／４０）和２．５％（１／４０）。  相似文献   

7.
用屠宰场绵羊卵巢和附睾进行胚胎体外生产的研究   总被引：3，自引：0，他引：3  
研究了从屠宰场得到的绵羊卵巢可采集的Ａ级卵母细胞数在不同月份的变化规律及运用屠宰场母羊的卵母细胞、公羊的附睾精子生产早期胚胎的可行性。结果表明在我国新疆地区，９、１０两个月份每个卵巢得到的平均Ａ级卵母细胞数显著高于其它月份（Ｐ＜０．０５），是进行绵羊体外受精研究的理想季节。卵巢卵母细胞经成熟培养后与附睾精子体外受精３０ｈ后，入孵卵母细胞在Ｍ１９９＋ＦＣＳ和Ｍ１９９＋ＦＣＳ＋ＣＣｓ培养液中的卵裂率分别为２２．４％和４４．５％；继续培养４～７ｄ，卵裂胚发育为１６－细胞以上的比例分别为６３．２％和８３．９％，差异极显著（Ｐ＜０．０１）。  相似文献   

8.
将８０只３０日龄红布罗鸡随机分为４组，半胱胺（ｃｙｓｔｅａｍｉｎｅ，ＣＳ）的添加量分别为０（对照）、１００、１５０、２００ｍｇ／ｋｇ体重。至５８日龄称重、宰杀、颈静脉采血，并用放免法对血液生长抑素（ＳＳ）和生长激素（ＧＨ）含量进行分析。结果：（１）与对照组相比，ＣＳ１００组净增重提高６．２％（Ｐ＜０．０５），其它剂量组增重无明显变化；（２）口服ＣＳ不改变仔鸡采食量，但饲料转化率ＣＳ１００、ＣＳ１５０、ＣＳ２００组分别提高５．７％、３．３％、６．３％；（３）与对照组相比，ＣＳ１００、ＣＳ１５０、ＣＳ２００组的血液ＳＳ含量分别下降７０．７％（Ｐ＜０．０５）、７６．２％（Ｐ＜０．０２５）和７６．１％（Ｐ＜０．０１），但ＧＨ水平只在ＣＳ１００组有明显升高（Ｐ＜０．０５），结果提示ＣＳ对仔鸡的作用同哺乳动物一样也呈现剂量依赖性  相似文献   

9.
试验用２８日龄艾维茵肉仔鸡１２０只，随机分成四组（１、２、３、４），各组饮水中添加氯化钾（ＫＣｌ），其浓度分别为０、０．１８％、０．２６％、０．３４％。试验鸡会温度控制在３４±１℃，试验期为１周，进行了饲养试验、代谢试验和比较屠宰试验。结果表明：能量的沉积和利用率处理组高于１组，尤其是４组显著高于１组（Ｐ＜０．０１），并高于２、３组（Ｐ＜０．０５）；粗蛋白的沉积及其沉积率处理组高于１组，胴体粗蛋白的沉积和利用率２组高于１、３、４组（Ｐ＜０．０５）。因此，饮水中加入０．３４％ＫＣｌ可提高肉仔鸡在高温下对能量的利用率，０．１８％ＫＣｌ则提高其对粗蛋白的利用率。  相似文献   

10.
BFF,rbGH对牛卵泡卵母细胞体外受精后发育的影响   总被引：12，自引：3，他引：9  
利用屠宰黄牛卵巢，对２～５ｍｍ卵泡卵母细胞的体外成熟（ＩＶＭ）、体外受精（ＩＶＦ）、受精卵的体外培养（ＩＶＣ）进行了系列研究。结果表明，在成熟培养液中单独添加１０％Ｄ０ＥＣＳ（发情当天牛血清）获得了卵泡卵母细胞受精后较高的卵裂率（６４．７％）、桑椹胚发育率（３９．９％）和囊胚发育率（２４．８％），说明在成熟培养液中单独添加Ｄ０ＥＣＳ是可行的；在含１０％Ｄ０ＥＣＳ的成熟培养液中再添加１０％或２０％ＢＦＦ（牛卵泡液），均能提高受精卵的卵裂率以及桑椹胚和囊胚的发育率，以添加２０％ＢＦＦ效果较好，其囊胚发育率（３５．０％）显著高于对照组（２４．８％，Ｐ＜０．０５）；在卵泡卵母细胞成熟培养系统和受精卵共同培养系统中添加１０μｇ／Ｌ重组牛生长因子（ｒｂＧＨ），虽对体外受精卵的卵裂率无显著影响（Ｐ＞０．０５），但能显著提高卵裂胚的囊胚发育率（Ｐ＜０．０５）  相似文献   

11.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

12.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

13.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

14.
Tropical Animal Health and Production -  相似文献   

15.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

16.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

17.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

18.
Comparison of different tests to diagnose feline infectious peritonitis   总被引：1，自引：0，他引：1  
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19.
An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.  相似文献   

20.
Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein  相似文献   

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