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1.
本试验对牛的扩张囊胚的冷冻保存技术进行了探讨。在２５℃温度下，利用ＥＦＳ４０的玻璃化溶液，将扩张囊胚直接移入此液中平衡后，投入液氨中一步法冷冻保存。或胚胎移入ＥＦＳ４０之前，在１０％ＥＧ溶液中预先处理，二步法冷冻保存。其解冻后获得了较高的发育率（分别为５９％ＶＳ６３％）。冷冻保存的胚胎移植后的妊娠率及产仔率分别高于对照组（８０％ＶＳ５５％；５５％ＶＳ２３％）。  相似文献   

2.
扩张囊胚玻璃化超低温冷冻保存及移植技术的研究   总被引：8，自引：0，他引：8  
本试验探讨了对鼠扩张囊胚玻璃化冷冻保存后，提高发育率的最佳条件。玻璃化溶液是用ＰＢＳ液稀释成的３０％聚蔗糖＋０．５Ｍ蔗糖混合法，再将乙二醇（ＥＧ）调制成２０、３０及４０％（ｖ／ｖ）的溶液，即ＥＦＳ２０、３０及４０。玻璃化冷冻保存是１０、２０及２５℃温度下，将扩张囊胚直接移入ＥＰＳ溶液后投入液氮中一步法令冻保存，其中２５℃下保存后的发育率最高（８７％）。继之将扩张囊胚用１０％ＥＧ溶液经５分钟处理后，再移入ＥＦＳ４０中二步法冷冻保存，发育率高达９４％。利用二步法冷冻保存的扩张囊胚移植后，妊娠受体的产仔率为６６％（１６８／２５５），同时照组产仔率６１％（８０／１３２）相比无显著性差异（Ｐ＞０．０５）。  相似文献   

3.
小鼠桑椹胚简易玻璃化冷冻技术再探讨   总被引：12，自引：0，他引：12  
本试验继小鼠扩张囊胚玻璃化冷冻保存成功后，在室温（２５℃）下利用不同浓度的ＥＦＳ玻璃化溶液，对小鼠的桑椹胚简易玻璃化冷冻技术进行再探讨。结果是胚胎在１０％ＥＧ溶液中预先处理５分钟，再移入事先配置好含有ＥＦＳ３０的０．２５ｍｌ塑料细管中１分钟平衡后直接投入液氮中冷冻，解冻后获得的发育率最高（９４％）。冻胚移植后妊娠率和产仔率分别为５６％（９／１６）及４２％（４９／１１６）。与对照组相比差异不显著（Ｐ＞０．０５）  相似文献   

4.
在25℃室温和37℃恒温台条件下，利用玻璃化冷冻溶液EFS30、EFS40、EDFS30或EDFS40，对小鼠4-细胞胚胎进行玻璃化冷冻保存．以解冻后培养72h的囊胚发育率为其体外发育能力的考核指标，同时对解冻后培养1～3h的胚胎进行移植以判定其体内发育潜力。开放式拉长塑料细管（OPS）二步法冷冻保存，即胚胎首先移入预处理液（10％EG或10％EG＋10％DMSO）中平衡30s，再移入玻璃化溶液中洗涤后吸入OPS管中，分别经35、30或25s后直接投入液氮中冷冻保存。一步法冷冻保存则无需预处理液处理。结果表明，小鼠胚胎4-细胞一步法和二步法冷冻后囊胚最高发育率分别为87．7％和88.6％，与对照组（93.0％）差异不显著（P〉0．05）。利用最佳冷冻组获得的143枚胚胎移植于12只假妊娠50～60h的受体母鼠，结果有4只妊娠产仔17只，妊娠产仔率为42．5％（17／40），与对照组59．4％（19／32）差并不显著（P〉0.05）。  相似文献   

5.
影响玻璃化冷冻兔胚胎效果的一些因素   总被引：4，自引：0，他引：4  
试验对影响玻璃化冷冻兔胚胎效果的一些因素进行探讨，以找出理想的玻璃化冷冻方法。在测试的５种玻璃化溶液中，含３５％乙二醇（ＥＧ）和１．０ｍｏｌ／Ｌ蔗糖的溶液（ＶＳ１）对胚胎的毒性最小。用ＶＳ１冷冻桑椹胚和囊胚的理想程序是：在室温下使胚胎分别在２０％ＥＧ和３５％ＥＧ中平衡２、３分钟后，移入ＶＳ１中，０．５分钟内（囊胚也可在２分钟后）投入液氮中冷冻。桑椹胚的存活率为９１．７％（３３／３６），囊胚的存活率为９７．１％（３３／３４）～９７．３％（３６／３７）。８～１６细胞胚胎的理想冷冻程序为：在室温下使胚胎在２０％ＥＧ、３５％ＥＧ中平衡２、３分钟，移入４℃的３７％ＥＧ＋１．０ｍｏｌ／Ｌ蔗糖溶液中平衡２分或１０分钟后冷冻，胚胎存活率分别为１００％（３７／３７）、８６．１％（３１／３６）。  相似文献   

6.
家兔孵化囊胚玻璃化冷冻保存技术的研究   总被引：2，自引：0，他引：2  
采用两种方法对家兔孵化囊胚作玻璃化冷冻保存在25℃室温下，将孵化囊胚直接移入EFS40溶液中短时间平衡后，直接投入液氮中冷冻保存(简称一步法)；或将胚胎在10％或20％EG溶液中经预处理后，再移入EFS40溶液冷冻保存(简称二步法)。结果表明，一步法冷冻后的胚胎发育率为68％，与对照组(鲜胚)的差异极显著(P<0.01)；二步法冷冻后的胚胎发育率高达93％，与对照组的差异不显著(P>0.  相似文献   

7.
小鼠2-细胞胚胎细管法和OPS法玻璃化冷冻保存技术的研究   总被引：8，自引：0，他引：8  
本试验在室温 (2 0℃和 2 5℃ )条件下 ,利用不同浓度的玻璃化溶液 (EFS和EDFS) ,对小鼠 2 细胞胚胎进行细管法和OPS法玻璃化冷冻保存。在 2 0℃室温条件下 ,用EFS4 0平衡 1min细管一步法冷冻 ,解冻后囊胚发育率仅为35 .0 % ,和新鲜 2 细胞体外培养的对照组 (6 5 .0 % )的差异极显著 (P <0 .0 1)。当 2 细胞胚胎在 10 %EG +10 %D溶液中预处理 5min ,再移入EDFS中平衡 30s二步法冷冻保存 ,解冻后囊胚发育率达 4 7.8%～ 4 8.8% ;当室温升至2 5℃时 ,二步法冷冻保存后 2 细胞的囊胚发育率达到 5 2 .2 % ,与对照组无显著差异 (P >0 .0 5 )。改用OPS二步法EFS30冷冻组保存后的 2 细胞胚胎的囊胚发育率高达 6 2 .2 % ,为试验中的最佳组。用最佳细管法和OPS法冷冻组解冻后培养至囊胚移植给受体母鼠均获得产仔  相似文献   

8.
本试验采用乙二醇为主体的ＥＦＳ４０玻璃化溶液,对小鼠扩张囊胚实行二步法玻璃化冷冻保存。结果保存１小时、１年和２年的胚胎,在体内外的发育率无显著性差异（Ｐ＞０．０５）。与对照组相比较也无显著性差异（Ｐ＞０．０５）。  相似文献   

9.
选用Ａ￣Ｅ５种混合保护液：Ａ．二甲亚砜（ＤＭＳＯ）＋乙醇（ＥＧ），Ｂ．甘油（ＧＬ）＋丙二醇（ＰＧ），Ｃ．ＧＬ＋ＥＧ，Ｄ．ＧＬ＋ＤＭＳＯ，Ｅ．ＰＧ＋ＥＦ，以２种冻前处理方法，对小鼠桑椹胚和囊胚进行一步冷冻，冷冻混合保护液中各种保护剂浓度均为２５％。法的冻前平衡液为ＶＳ２的对倍稀释液；法的冻前平衡液中，前一种保护剂浓度为１０％，后一种保护剂浓度为２０％。胚胎于室温（２０℃）下在ＶＳ１中平衡５ｍｉｎ或Ｖ  相似文献   

10.
转基因兔胚胎玻璃化冷冻保存的研究   总被引：4，自引：0，他引：4  
在２５℃条件下,将兔体外受精精子载体转基因兔桑椹胚置于含有４０％乙二醇、１８％Ｆｉｃｏｌ、０．３ｍｏｌ蔗糖的ｍＰＢＳ溶液（ＥＦＳ４０）中平衡２分钟,然后直接投入液氮,成功地进行了玻璃化冷冻保存。解冻后桑椹胚发育至囊胚和孵化囊胚的比例分别为６５．８１％和３９．２４％,与未经冷冻的鲜胚发育比例（７１．０５％和４３．４２％）相比,没有明显的差异。７８枚经玻璃化冷冻和解冻的桑椹胚移植给５只受体,其中２只妊娠,共产下８只活仔兔。  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
Tropical Animal Health and Production -  相似文献   

14.
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   

15.
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   

16.
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   

17.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

18.
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   

19.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

20.
<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.  相似文献   

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