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1.
羊超数排卵影响因素的分析   总被引:4,自引:0,他引:4  
超数排卵(简称超排)是以各种外源性促性腺激素诱发动物卵巢的多个卵泡发育并排出多个具有受精能力卵的过程。超排是胚胎移植最重要的技术环节,对于提高优良母畜的繁殖能力和品种改良具有重要意义,同时也为动物克隆和转基因动物生产等提供卵子和胚胎来源。目前,尽管超数排卵的方法已广泛应用,但超排的胚胎回收率和可用胚胎数还不稳定,影响了胚胎移植的进一步推广和应用。本文通过对超排影响的动物品种、个体差异、激素、超排处理方案、采胚方法、重复超排、年龄、营养状况、季节等诸多因素的分析,旨在为提高动物的超排效率提供借鉴。1影响超…  相似文献   

2.
羊超数排卵的方法及影响其效果的因素   总被引:4,自引:0,他引:4  
应用外源促性腺激素诱发母畜卵巢多个卵泡发育并排出具有受精能力的卵子的方法称为超数排卵(superovulation),简称"超排".超排是胚胎移植的重要的技术环节,对于提高优良母畜的繁殖力和品种改良具有重要意义,同时也为动物克隆和转基因动物生产提供卵子和胚胎来源.目前,尽管超排的方法已广泛应用,但超排的效果还不稳定,影响了胚胎移植的进一步推广和应用.  相似文献   

3.
超数排卵简称"超排",是以各种外源性促性腺激素诱发动物卵巢的许多卵泡发育并排出具有受精能力的卵子的过程.通过对实验动物进行超数排卵,可以一次性获得比正常情况下排出多数倍的成熟卵母细胞,受精后获得处于不同发育阶段的胚胎,不仅能开发利用卵巢上的卵母细胞资源,而且能提高优良母畜的繁殖能力,对加速品种改良和提高动物繁殖率都具有重要意义.  相似文献   

4.
PMSG在波尔山羊超数排卵中的应用   总被引:1,自引:0,他引:1  
以各种外源促性腺激素诱发动物卵巢的许多卵泡发育并排出具有受精能力的印子的过程称为超数排卵,简称超排。超排是进行家畜胚胎移植的重要手段,对提高优良母畜的繁殖能力和加速品种改良具有重要的意义。PMSG是子宫内膜产生的一种糖蛋白激素,近年来被广泛应用于波尔山羊等家畜的超数排卵。  相似文献   

5.
牛超数排卵的方法及影响其效果的因素   总被引:4,自引:0,他引:4  
应用外源促性腺激素诱发母畜卵巢多个卵泡发育并排出多个具有受精能力的卵子的方法,称为超数排卵(Superovulation),简称“超排”。由于大多数家畜是单胎或双胎动物,单纯的胚胎移植技术对提高动物的繁殖率是很有限的,因此配合超排进行家畜胚胎移植是一种重要手段。1牛超排所用的激素和方法1.1牛超排使用的激素牛超排所用的激素主要有促卵泡素(FSH),孕马血清促性腺激素(PMSG),前列腺素(PGF2α)及其类似物,促黄体素(LH),孕激素,促性腺素释放激素(GnRH),人绒毛膜促性腺激素(HCG)等。1.2超排方法1.2.1FSH+PG法在发情周期的9~13天中的…  相似文献   

6.
超数排卵简称"超排",是以各种外源性促性腺激素诱发动物卵巢的许多卵泡发育并排出具有受精能力的卵子的过程,它既能提高良种母畜的繁殖潜力,又能为胚胎学、生殖生理学等提供一种研究手段[1].  相似文献   

7.
超数排卵在动物胚胎工程技术的体内胚生产中起关键作用,不同品种甚至个体对超数排卵的反应不同。人绝经期促性腺激素(HMG)是从绝经期妇女尿液中提纯得到的具有促卵泡素(FSH)活性的蛋白质激素,在医学上广泛应用于诱导排卵和治疗不育不孕症。本试验以安格斯青年母牛为超排供体,采用分次肌肉注射激素方法进行超排处理,比较了HMG与FSH用于安格斯母牛超数排卵的效果。B超检查发现,HMG和FSH超排处理后牛只两侧卵巢上直径>1cm的卵泡数分别为10.33±0.52和9.25±0.46个,二者差异不显著(P>0.05),表明HMG与FSH同样安全有效;总剂量1 400IU的HMG或FSH用于安格斯母牛超排后B超检查卵巢没有发现异常变化,说明该剂量是用于安格斯母牛超数排卵的安全有效剂量。  相似文献   

8.
超数排卵(superovulation)简称超排,是指在母牛发情周期中适时为其注射促性腺激素,而促使母牛卵巢比自然状态下有更多的卵泡发育并排出成卵的技术。使用激素类药物对动物进行超数排卵是进行胚胎移植、转基因等研究的方法之一,通过超数排卵可以获得大量成熟的卵子。尽管目前超排的方法已被广泛应用,但超排产生的胚胎依然有20%左右而不能用于移植。究其原因是现有的超排方法获卵率和可用的胚胎质量还不十分稳定,这严重阻碍了该项技术的推广应用。本文意在探讨超数排卵的方法和提高超排效果的技术措施,以为畜牧业生产提供技术指导。  相似文献   

9.
哺乳动物卵泡发生及发育调控刘素娟(西北农业大学动物医学系陕西杨陵712100)随着胚胎工程技术的迅速发展,胚胎的需求量越来越大,充分了解卵泡的发生过程,对改进超排技术和提高卵巢卵母细胞的利用率,完善体外受精技术均具有重要意义.现将近几年来在此方面的研...  相似文献   

10.
家兔超数排卵影响因素探讨   总被引:1,自引:0,他引:1  
超数排卵(简称超排),是生物工程中一个重要的基本技术环节,通过对动物的超排处理,可以获得大量卵母细胞和早期胚胎,加速动物的增殖和改良。本文根据作者近年来在家兔体外受精、胚胎分割等研究中所获资料,探讨影响家兔超数排卵的若干因素(如品种、季节、激素的使用、左右侧卵巢等),旨在揭示家兔超数排卵的规律,为今后进行家兔胚胎移植的深入研究,提供科学依据。 一、材料与方法 1.实验动物 所用实验动物为本地市售  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.
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   

13.
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   

14.
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   

15.
16.
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   

17.
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   

18.
19.
A knowledge of the microbiological status of milk and of the different structures in the mammary glands has great importance in elucidating the pathogenesis of mammary gland infections. The objective of this study was to evaluate the microbiological status of various structures in the mammary glands from naturally infected dairy cows following slaughter. A total of 94 samples of milk, 184 samples of mammary parenchyma, 168 samples of gland cisterns, and 168 samples of teat cisterns were collected for microbiological examination. Microorganisms were detected in 59.9% of all samples, 67.0% of the milk samples, 70.1% of the mammary parenchymas, 55.9% of the gland cisterns and 48.8% of the teat cistern samples. When all samples were considered, coagulase-negative Staphylococcus were the most prevalent (35.7%) followed by coagulase-positive Staphylococcus (12.2%), Corynebacterium bovis (2.4%), Prototheca sp. (1.9%), and Streptococcus dysgalactiae (1.5%). There was a significantly higher occurrence of microorganisms in the milk and mammary parenchyma compared to the gland cisterns and teat cisterns. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

20.
Four grass plots were sequentially contaminated with goat faeces containing known numbers of unembryonated eggs of predominantly Haemonchus contortus and Trichostrongylus spp. between October 1982 and April 1983. Four other plots were similarly contaminated with sheep faeces between February and May 1987. An additional plot was repeatedly contaminated with sheep faeces from February to April 1987. Populations of free-living stages in faeces and of infective larvae (L3) in the herbage were subsequently monitored until the end of April and June of 1983 and 1987 respectively. During February and May 1987 two control cultures of sheep faeces were incubated in the laboratory at 25°C–30°C and at a constant temperature of 50°C and the free-living development was also monitored. L3 developed very readily in the faeces cultured at 25°C–30°C and in those spread on a grass plot in October, at the end of the wet season, but developed less on the plot contaminated in May at the start of the wet season. Worm eggs in faeces deposited on plots during the hot dry season (December to April) or incubated at 50°C died and disintegrated after 24–48 h exposure to the high environmental temperatures. The results indicate that it is unlikely that gastrointestinal nematodes of sheep and goats can develop or survive on open pasture during the dry season in the Nigerian derived savanna zone.  相似文献   

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