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1.
为了确定猪体细胞克隆胚胎的受体母猪最佳发情阶段,本研究比较了供受体同期化方案对猪体细胞克隆胚胎输卵管内移植后30 d受胎率和妊娠足月率的影响。将体外培养2 d的猪体细胞克隆胚胎,移植到发情第1~2天的受体母猪。根据受体母猪卵泡发育与排卵状况将受体猪群分为2个类别:卵泡发育处于即将排卵或正在排卵阶段(组一);卵泡发育处于排卵前阶段或完全排卵阶段(组二)。结果发现:(1)组一6头受体母猪胚胎移植后30d受胎率为100%;而组二10头受体母猪受胎率为40%,二者差异显著(P0.05)。(2)组一6头受体母猪全部产仔,妊娠足月率为100%;组二10头受胎母猪2头产仔,妊娠足月率为20%,二者差异极显著(P0.01)。以上结果表明:体外培养2 d的猪体细胞克隆胚胎发育阶段与即将排卵或正在排卵的受体母猪的子宫环境同期性最好,得到了理想的胚胎移植效率。  相似文献   

2.
枫泾猪母猪生殖器官和性机能的发展   总被引:1,自引:0,他引:1  
试验用不同年龄枫泾母猪106头。结果表明,母猪生殖器官相对生长率以90日龄前最高。8月龄母猪两侧子宫角平均长度为108±22.4厘米。初生小母猪卵巢中即有初级卵泡,30日龄时出现早期生长卵泡。首次外阴部肿胀的日龄为77.7(18—89)天。小母猪初情期发生在133.6(90—185)日龄。8月龄青年母猪和成年母猪分别在发情开始后36—41和27小时排卵。初情期、8月龄和成年母猪的排卵率分别为12(4—30)、16.7(12—25)和31.0(22—45)个。8月龄和成年母猪所排卵子的受精率分别为95.3%和68.6%。未受精卵和2—16细胞胚胎的外径(不计透明带),波动在120~135μ之间。发情开始后约100小时胚胎进入子宫角。  相似文献   

3.
为了提高家兔繁殖力,使用不同剂量的FSH对家兔进行了超数排卵研究,结果表明:采用高剂量FSH处理母兔的平均排卵点数与平均卵泡发育数显著(P〈0.05)高于低剂量FSH组,两种处理方法的平均卵泡囊肿数与平均卵泡数则差异不显著(P〉0.05)。家兔早期胚胎发育观察结果表明:母兔交配后24h采胚所获取的胚胎大多处于1细胞期,交配后30h胚胎多处于2细胞期,交配后35h胚胎多处于4细胞期。采用52IU FSH进行超数排卵处理,对家兔的胚胎发育无影响。  相似文献   

4.
给休情期性成熟母犬肌注 PGF2α(0 .5 m g/ kg) ,2 4 h后肌注 e CG(5 0 IU/ kg) ,再经 12 0 h后肌注 h CG(2 0 U/ kg) ,诱导其发情。将诱导发情的母犬与公犬交配 ,于交配后 16 d,摘取卵巢、子宫 ,观察其卵泡发育和胚胎着床情况。结果表明 ,药物处理可明显促使母犬提前结束休情期而进入发情期 (9/ 10 ) ,促进卵巢内卵泡发育 (P<0 .0 1) ,并使更多的胚胎着床 ,每只母犬子宫胚胎着床点为 (17.4± 2 .2 )个 ,提示 3种生殖激素联合应用可提高母犬繁殖率  相似文献   

5.
本研究旨在从配种次数、配种时间以及促排卵药物的使用3个方面对后备母猪同期排卵-定时输精技术方案进行优化。将后备母猪随机分成6组:(1)自然发情对照组:母猪自然发情、配种;(2)简式定时输精组:使用烯丙孕素性周期同步化后母猪自然发情配种;(3)传统定时输精组:母猪性周期同步化后,经过孕马血清促性腺激素和戈那瑞林处理使得卵泡发育和排卵同步化,无需查情,固定时间输精;(4)两点式查情定时输精组:在传统定时输精的基础上增加了注射促排卵药物时和配种后24 h 2个查情、配种时间点;(5)诱导发情促排实时输精组:性周期和卵泡发育同步化后,母猪发情时注射戈那瑞林促排卵,实时输精;(6)诱导发情实时输精组:母猪性周期和卵泡发育同步化处理后,实时输精。使用B超监测各组母猪卵泡发育和排卵情况,评价不同程序对母猪发情时间、排卵集中度、卵泡囊肿和繁殖性能的影响。结果显示:与简式定时输精组相比,注射外源促性腺激素改变了卵泡生长速度和排卵时间,缩短了最后一次饲喂烯丙孕素到发情的间隔时间,但是并没有改变发情-排卵间隔时间和排卵前卵泡大小。诱导发情促排实时输精组母猪妊娠率(93.52%vs 76.85%)和分娩率(8...  相似文献   

6.
本实验选择 12只雌性银狐 ,观察繁殖期发情、排卵、受精及胚胎早期发育情况。研究结果表明 ,银狐属季节性单次发情动物 ,繁殖期处于 1月末至 3月初 ,排卵时间在初次接受交配后 2 5~ 2 7小时 ,持续排卵时间为 3天左右 ,而且陆续排卵。在初次配种后 3~ 4天 ,6~ 7天 ,9~ 10天和 11~ 12天 ,回收的胚胎分别发育到 3~ 4细胞 ,8~ 32细胞 ,桑椹~早期囊胚和扩张囊胚阶段。  相似文献   

7.
在猪胚胎附植前期,在不同时期的母体子宫环境下,诱导胚胎发育通过胎儿和胎盘的发育状况确定猪胚胎移植的最佳时期。用24头(其中12头为供体,另12头为受体)出现发情症状24h之后的约克夏母猪与约克夏公猪交配,在妊娠60h,从供体输卵管中冲出胚胎(此时胚胎处于1~4细胞期),分别移入处于发情期36h、60h、84h的受体输卵管中。以胚胎的日龄计算,在妊娠的112d取出受体的子宫,分别检测胎儿体重、胎盘的重量、胎盘的表面积及胚胎附植位点的长度。通过比较,发情3.5d和2.5d移入受体的胎儿,虽然幼仔的数量相近(9.1±0.9),但胎儿比较重(分别为1.44±0.05kg,1.23±0.04kg,p<0.001),并有较大的胎盘表面积(1793±60cm2,1459±43cm2,p<0.01)和较长的附植位点(32.1±1.5cm,24.9±0.6cm,p<0.001)。表明胚胎位于输卵管时进行移植效果比较理想。  相似文献   

8.
早期研究表明:经产母牛输精期卵泡大小显著影响其受胎率和授精后胚胎/胎儿死亡率,但对自然排卵的母牛受胎率没有影响。本研究目标是分析青年母年受胎率、胚胎/胎儿死亡率同排卵前期卵泡大小、诱导或自发排卵后血液循环中雌二醇浓度之间的关系。青年母牛分为成2组不同的繁殖牛群进行人工授精:①利用同期发情和诱导排卵后授精(TAI,n=98);②在23 d发情周期中,利用电子检测仪检测母牛发情后12 h授精(自然排卵,n=110)。利用直肠超声波检查输精时卵泡大小和输精后27、41、55和68d怀孕状态。测定的青年母牛中仅有6头出现后期胚胎或早期胎儿死亡。繁殖牛群和卵泡大小的相互作用并不影响母牛受胎率。结合繁殖牛群数据分析,卵泡大小对受胎率的对数回归特征表现为曲线(P<0.01),并且预测出卵泡大小为12.8mm时,受胎率最高(为68.0±4.9%)。卵泡直径小于10.7 mm或大于15.7 mm时,受胎率都较直径为12.8 mm卵泡低。直径小于10.7 mm卵泡(有28%的青年母牛妊娠)则比大于15.7 mm的卵泡(仅有4%)更易受孕。授精后24 h内有发情行为的青年母牛所排卵泡直径(12.2±0.2 mm)、雌二醇浓度(9.9±0.6)以及妊娠率(63%)都显著高于无发情行为的母牛(分别为11.1±0.3mm,6.6±0.7,20%)(P<0.01)。然而,对卵泡大小差异进行分析后,发现妊娠率又与发情行为表现和雌二醇浓度无关。因此,血清雌二醇浓度和发情行为对妊娠的影响似乎通过卵泡大小来介导的,并且优化卵泡大小的管理实践可以提高受胎率。  相似文献   

9.
骆驼的繁殖生理(第二报)骆驼的性活动   总被引:3,自引:0,他引:3  
母驼的发情季节是由冬至开始,因而性活动和白昼变长有关。发情时为诱导排卵,即交配才能引起排卵;不交配时,卵泡连续发育及萎缩。排卵机制和兔子不同,刺激子宫颈不能引起排卵。凡是发育至直径1厘米以上的卵泡,交配时间达2.5分钟者,配后30—48小时均排卵;两个卵泡同时正常发育时,配后一起排卵,但未见生双胎者。卵泡已经开始萎缩的,配后不能引起排卵。卵泡发育至最大时,直径(或长径)平均为1.69(1.1—2.4)厘米。周期黄体的最大直径(或长径)平均为1.5(1.1—2.3)厘米。公驼有明显的发情季节,12月10日左右开始,4月中旬结束。性交的持续时间一般为2—4(1—6)分钟。每次射精量一般平均为4.3(2—7)毫升,精子数为每毫升平均6.15(2.2—15.5)亿。  相似文献   

10.
山羊早期胚胎发育的初步研究   总被引:8,自引:0,他引:8  
本实验以黑龙江地方山羊为材料,经FSH超数排卵后,在不同时间屠宰母山羊,并冲洗输卵管及子宫,获取新鲜卵及各发育时间的胚胎。实验中发现山羊的排卵时间为发情开始后约30小时。受精卵的第一次卵裂的发生在排卵24小时以后。2细胞、4细胞、8细胞、16细胞、桑椹及胚泡期胚胎所处的时间分别为排卵后约32~42、48~52、62、72、96小时以及7~8天。16细胞期以前的胚胎移行于输卵管中,桑椹胚及胚泡则移行于子宫中。在每一时间从每只羊中所收集的胚胎基本上处于几个相邻的发育时期。在桑椹胚的动物极有明显的突起,这可能是内细胞群已开始形成的标志。到胚泡期时,胚胎体积增大,透明带变薄。正在孵化或已经孵化的胚泡中,内细胞群外端无滋养层细胞包围。  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.
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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