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1.
卵母细胞体外成熟是进行体外胚胎生产的关键环节,但目前哺乳动物卵母细胞体外成熟培养存在成熟率低、受精率低和胚胎质量差等问题。卵母细胞体外成熟培养体系是制约卵母细胞体外成熟效果的重要因素,共培养体系可提高哺乳动物卵母细胞体外成熟效率。本文主要从卵母细胞成熟与卵泡细胞共培养、与裸卵共培养和与间充质干细胞共培养3个方面综述共培养体系对哺乳动物卵母细胞体外成熟的影响,为共培养体系应用于卵母细胞体外成熟提供理论依据和研究借鉴。  相似文献   

2.
Over the last several decades, a number of therapies have been developed that manipulate ovarian follicle growth to improve oocyte quality and conception rates in cattle. Various strategies have been proposed to improve the responses to reproductive biotechnologies following timed artificial insemination (TAI), superovulation (SOV) or ovum pickup (OPU) programmes. During TAI protocols, final follicular growth and size of the ovulatory follicle are key factors that may significantly influence oocyte quality, ovulation, the uterine environment and consequently pregnancy outcomes. Progesterone concentrations during SOV protocols influence follicular growth, oocyte quality and embryo quality; therefore, several adjustments to SOV protocols have been proposed depending on the animal category and breed. In addition, the success of in vitro embryo production is directly related to the number and quality of cumulus oocyte complexes harvested by OPU. Control of follicle development has a significant impact on the OPU outcome. This article discusses a number of key points related to the manipulation of ovarian follicular growth to maximize oocyte quality and improve conception rates following TAI and embryo transfer of in vivo- and in vitro-derived embryos in cattle.  相似文献   

3.
分离培养牦牛输卵管上皮细胞和卵泡颗粒细胞的目的是克服体外受精中早期胚胎发育阻断,建立有利于牦牛早期胚胎体外发育的共培养体系.采集牦牛输卵管上皮细胞进行原代及传代培养,同时从卵泡液中获取颗粒细胞进行原代培养,培养过程中观察2种细胞的生长方式和形态特点.输卵管上皮细胞贴壁生长时,呈多边形,且呈单层成簇生长.培养144 h~216 h,可形成细胞单层.颗粒细胞贴壁生长时,呈现聚集生长特性,贴壁细胞形状不规则,呈放射状.培养72 h~96 h,形成颗粒细胞单层.  相似文献   

4.
This study was undertaken to examine pre- and postimplantation developmental potency of cryopreserved embryos that had undergone in vitro growth (IVG), maturation (IVM) and fertilization (IVF) of oocytes from the preantral follicle stage. An oocyte culture system for IVG and IVM was used in oocyte-granulosa cell complexes (OGCs) derived from preantral follicles in 12-day-old mice. The rate of oocyte maturation was improved by the addition of gonadotropins (FSH/LH) and cytokines (IGF-I/SCF) to culture medium for IVG. During culture for IVG, estradiol-17β and progesterone concentrations increased progressively to the latter period of culture. This culture system enabled IVG, IVM, IVF and pre- and postimplantation development. From 90 cryopreserved 2-cell stage embryos transferred into recipients after warming, 10 live pups were produced. Cryopreservation of embryos by vitrification at the 2-cell stage showed no harmful effect on development to the blastocyst stage or on the cell numbers of the inner cell mass (ICM) and trophectoderm (TE). This study demonstrated that embryos derived from oocytes grown in vitro have tolerance for vitrification and competence to develop to term after warming. This IVG-IVM-IVF technology combined with embryo cryopreservation might be useful for assisted reproduction in mice.  相似文献   

5.
Many factors affect development of mammalian preimplantation embryos in vitro. It is well known that in vitro development of bovine embryos is highly affected by culture condition including energy source, growth factors, pH or gas environment. Many efforts have been made towards the suitable environments which can successfully support embryo development in vitro. For a rapid growth and differentiation, embryo requires energy by utilizing ATP, NADPH with oxygen molecules. These energy substrates are produced from the electron transport chain in the mitochondria. In addition to energy production, reactive oxygen species (ROS) are also generated as by-product of such energy production system. ROS production is sensitively controlled by the balance of oxidizing and reducing status and affected by several antioxidant enzymes such as superoxide dismutase (SOD), Catalase, glutathione peroxidase (GPx) or low molecular weight thiols such as glutathione (GSH). Imbalance of oxidation and reduction causes production of excess ROS, which causes the developmental arrest, physical DNA damage, apoptosis induction or lipid peroxidation. Environmental oxygen condition during embryo culture also highly affects embryo development as well as intracellular redox balance. Several studies have revealed that regulation of intra- and extra- cellular reducing environment by reducing excess ROS by using antioxidants, reducing oxygen concentration are effective for improving embryo development. Also, recent studies have demonstrated the difference in gene expression affected by oxidative stress. This review briefly summarizes the effects of ROS and the role of redox balance on preimplantation embryos for improving the efficiency of in vitro production of mammalian embryos.  相似文献   

6.
山羊体外受精技术的研究进展   总被引:2,自引:0,他引:2  
本文主要阐述了山羊体外受精技术,特别是山羊卵母细胞的采集和体外成熟,体外受精以及胚胎培养过程中的一些研究进展,及其山羊体外受精技术的非常广阔的前景。  相似文献   

7.
The objective of this study was to examine whether high concentrations of epidermal growth factor (EGF) and/or insulin-like growth factor I (IGF-I) would have a beneficial effect on bovine embryo development in vitro and to obtain normal calves by using an ovum pick up method and embryo culture in a chemically defined medium. When compared with controls, EGF (100 or 200 ng/ml) or IGF-I (50 or 100 ng/ml) significantly increased the rate of embryos that developed into blastocysts during an 8-day culture after the in vitro fertilization of oocytes obtained from ovaries from a slaughterhouse. IGF-I induced a dose-dependent increase in cell number in both the inner cell mass and the trophectoderm, whereas EGF stimulated proliferation only in the inner cell mass. A combination of EGF (100 ng/ml) and IGF-I (50 ng/ml) produced an additive effect, and embryos developed into blastocysts at a comparatively high rate (27.9%) compared with controls (12.0%). A similar rate of development was achieved using a combination of EGF and IGF-I in the culture of embryos following ovum pick up by ultrasound-guided transvaginal follicular aspiration and in vitro fertilization, and 5 blastocysts that developed after the culture were transferred into uteri; two embryos implanted, and normal calves were born. These results suggest that the combined use of EGF and IGF-I makes bovine embryo culture in a chemically defined medium a practical and useful procedure for producing blastocysts, and its application to embryo culture following ovum pick up and in vitro fertilization could be useful for producing normal calves.  相似文献   

8.
In vitro Follicle Growth: Achievements in Mammalian Species   总被引:4,自引:0,他引:4  
The exact mechanisms regulating in vivo folliculogenesis in mammalians have only been partly unravelled. Some processes, such as the initiation of growth of primordial follicles are still poorly understood. This increases the difficulty to culture follicles in vitro as the primordial follicles will be the ultimate starting material for culture.
There are important species differences in regulation and timing of maturation, which makes it difficult to transpose techniques.
Only in the mouse model, live pups were born when primordial or early preantral follicles were cultured entirely in vitro . Although no systems are as yet permitting complete in vitro culture of early follicle stages in large animals or humans, parts of folliculogenesis have been successfully reproduced in vitro . This review summarizes achievements of the last years in follicle culturing starting off at several stages of development.
Future applications of in vitro follicle culture include fertility preservation for humans, preservation of rare animal species and creation of oocyte banks for research.  相似文献   

9.
奶牛体外受精胚胎的不同培养方法对比试验   总被引:3,自引:0,他引:3  
以屠宰场奶牛卵巢为试验材料,研究体外、体内培养法对体外受精胚胎发育的影响。①体外受精胚胎分别在加输卵管上皮细胞单层和颗粒细胞单层(2×106个/ml)的体外培养体系的培养液中培养与临时受体绵羊体内培养对比试验。结果显示:在培养的第8 d囊胚发育率无显著差异,体外培养体系囊胚形成主要集中在第8 d(受精日为第0 d)。体内培养体系囊胚的形成多数在第7 d。加体细胞的体外培养体系与体内培养法囊胚生成率无显著差异,但却显著好于不加体细胞的简单体外培养法。②进行2种方法生产的胚胎的程序冷冻、解冻敏感性试验。结果显示:体内培养法和普通体外法生产的胚胎解冻后存活率(90%;60%)和囊胚孵化率(85.7%;44.4%)存在极显著差异(P<0.01)。  相似文献   

10.
动物摄取营养是为了生存和生产。繁殖是动物的一种特殊生产 ,营养状况与其密切相关。近些年奶牛在泌乳量得以提高的同时 ,繁殖能力下降。营养主要通过影响奶牛的排卵率、胚胎存活率等直接影响受精率。适量的限饲可以提高奶牛优质胚胎的数量 ,但若出现能量负平衡 ,则会通过抑制促黄体素 (L H)的分泌和降低卵巢对 L H的敏感性 ,使卵巢上的优势卵泡不能及时排出 ,容易形成卵巢囊肿 ,从而影响下一轮卵泡发育。营养状况可以改变血液中孕酮的浓度而改变受胎率。营养状况也会通过改变血液中的尿素和氨的浓度来改变子宫内 PH值的变化 ,从而影响胚胎的着床和早期发育。另外 ,营养还可以改变动物机体内的胰岛素和胰岛素样生长因子的水平来影响胚胎的发育。因此 ,在生产中通过改善营养状况 ,可以充分发挥奶牛的生产性能。  相似文献   

11.
The coenzyme Q10 (CoQ10) is a potent antioxidant with critical protection role against cell oxidative stress, caused by the mitochondrial dysfunction. This study evaluated the effects of CoQ10 supplementation to in vitro maturation (IVM) or embryo culture media on the maturation, fertilization and subsequent embryonic development of pig oocytes and embryos. Maturation (Experiment 1) or embryo culture (Experiment 2) media were supplemented with 0 (control), 10, 25, 50 and 100 μM CoQ10. The addition of 10–50 μM CoQ10 to the IVM medium did not affect the percentage of MII oocytes nor the fertilization or the parameters of subsequent embryonic development. Exogenous CoQ10 in the culture medium neither did affect the development to the 2–4‐cell stage nor rates of blastocyst formation. Moreover, the highest concentration of CoQ10 (100 μM) in the maturation medium negatively affected blastocyst rates. In conclusion, exogenous CoQ10 supplementation of maturation or embryo culture media failed to improve the outcomes of our in vitro embryo production system and its use as an exogenous antioxidant should not be encouraged.  相似文献   

12.
We investigated the effect of group culture on bovine embryo development, and also investigated the effect of embryo-culture conditioned medium on developmental competence of individually cultured bovine embryos. Slaughterhouse-derived bovine oocytes were matured and fertilized in vitro. The presumptive zygotes were cultured individually or cultured in groups of 2 to 5 embryos with a constant culture density (5 mul/embryo). After 7 days of culture, the rates of embryos developed to the blastocyst stage were significantly higher (P < 0.05) in group cultures of more than 3 embryos/drop than for embryo culture of 1 or 2 embryos/drop. These results suggest a beneficial effect of group culture may be exerted by possible growth promoting factors secreted by embryos. In the next experiment, we investigated the effect of timing of fresh medium replacement on the development of embryos cultured in groups. The blastocyst formation rate was lower when culture medium was replaced freshly on days 2-4 after fertilization than on days 5-6. The blastocyst formation rates of single-cultured embryos were significantly (p < 0.05) increased by the addition of conditioned medium derived from multiple-embryo culture. These results indicate that group culture promotes embryo development and that embryo culture-derived conditioned medium is effective for supporting development of single cultured embryos.  相似文献   

13.
14.
Two groups of mouse preantral follicles with diameters of 125-150 and 151-175 microm were cultured individually for 6 days in a medium supplemented with FSH and fetal calf serum to determine their in vitro growth characteristics. Their oocyte capacity for maturation and development to the blastocyst stage following in vitro fertilization was also assessed. Antral formation rate at the end of culture was higher in the follicles of 151-175 microm (89%) than 125-150 microm (76%). The timing of antrum formation was different between the two follicle categories: most 151-175 microm follicles formed antra earlier than 125-150 microm follicles (days 4 and 5 vs. 5 and 6). However, follicle diameters at the time of antrum formation were the same regardless of the initial size and the culture period. Maturation rates of the oocytes derived from both categories of in vitro grown follicles (70 and 62%) were not different from those of oocytes from in vivo grown follicles (74%). The in vitro derived oocytes, however, showed less cleavage (30 and 35%) than the in vivo derived oocytes (89%). Although the oocytes from both follicle categories developed to the morula stage after in vitro fertilization, blastocysts were only obtained from oocytes derived from the 151-175 microm category. These results demonstrate that an individual follicle culture system using a medium with FSH and fetal calf serum supports in vitro growth of mouse preantral follicles with diameters of 151-175 microm to the preovulatory stage, and that their oocytes have the capability to develop to the blastocyst stage.  相似文献   

15.
Dry period and early post-partum management are decisive factors for fertility in lactating dairy cows. Previous studies have shown that decreased dry matter intake (DMI) and increased non-esterified fatty acids (NEFA) negatively affect fertility and subsequent milk production. The traditional dry period decreases DMI prior to parturition, resulting in a decrease in energy intake. A negative energy balance increases NEFA concentration, and increased NEFA may impair the immune system, especially by decreasing neutrophil function prior to parturition. Earlier studies have shown that post-partum health disorders, including retained placenta and metritis, were correlated with periparturient neutrophil function. In addition, decreased DMI is also linked to a reduced body condition score (BCS) in dairy cows. These events in the periparturient period negatively affect fertility. Some manipulation, such as shortening the dry period, may be a solution to increased DMI in the periparturient period, preventing post-partum disorders and subsequent fertility issues. This article aims to explain the effects of shortening the dry period on reproduction and early post-partum treatments to improve fertility. In addition, timed artificial insemination protocols will be discussed for use during the post-partum period to improve fertility in dairy cows.  相似文献   

16.
The purpose of this study was to determine whether or not embryos derived from in vitro fertilization of oocytes from persistently infected (PI) cattle would contain infectious virus. Three in vitro embryo production treatment groups were assessed: 1) oocytes and uterine tubal cells (UTC) free of bovine viral diarrhoea virus (BVDV) (negative control), 2) oocytes free of BVDV fertilized and cultured in media containing UTC obtained from PI heifers, and 3) oocytes from PI heifers fertilized and cultured in media containing UTC free of BVDV. The developmental media, UTC and embryos (individual or groups of five) were assayed for virus. Virus was not isolated from any samples in treatment group 1. As shown in previous studies, a proportion of embryo samples were positive for BVDV in treatment group 2. In treatment group 3, the virus associated with the oocytes contaminated the developmental media and infected susceptible co-culture cells used during fertilization and culture. In addition, 65% (11/17) of the degenerated ova from treatment group 3 had infectious virus associated with them. While none of the ova developed into transferable embryos, the study did confirm that use of oocytes from PI cows could lead to amplification of BVDV and cross contamination during in vitro embryo production.  相似文献   

17.
水牛的繁殖受诸多因素的影响。为提高其繁殖力 ,多种繁殖生物技术得到大量研究。水牛精子的稀释、冷冻及人工授精已基本程序化 ,并得到了广泛推广。通过超数排卵和胚胎移植的研究 ,获得了水牛胚胎移植的后代。水牛卵母细胞的采集、体外成熟、体外受精和受精胚的培养也得到大量研究 ,并成功产出体外受精水牛。在水牛胚胎冷冻和移植的研究方面也取得成功并产犊。细胞核移植、基因组和基因图谱等新兴生物技术在水牛上也得到初步研究。随着转基因等生物技术的进一步发展 ,水牛的遗传资源将得到更好的开发  相似文献   

18.
A key factor in the hygienic application of embryo transfer (ET) and its associated technologies is effective risk management. This depends on knowing what the risks of infectious disease transmission are and how they can be reduced or removed. Risk assessment depends on a knowledge of the pathogenesis of the disease, the procedures used in ET and its associated technologies and the results from research into infectious disease transmission by embryos or through ET. Two approaches can be taken to ensure the safe health status of the embryo: 1) by determining that the donor animals (male and female) are free from specific diseases, or 2) by ensuring that the zona pellucida (ZP)-intact embryo is collected in a sanitary manner and handled (washed, treated, evaluated, etc.) according to recommended procedures. The former approach is applicable to diseases on which no or insufficient research has been done to determine the risk of their being transmitted by embryos or where the results of research done indicate a risk of the disease being transmitted. The latter approach is a preferred option with diseases where results of research done indicate that the risk of their being transmitted by embryos collected from infected or recovered donors is negligible. Infectious diseases for which research results indicate negligible risk of transmission by ZP-intact (ZP-I) embryos collected from infected or recovered donors include: pseudorabies (Aujesrky's disease), hog cholera (swine fever), foot and mouth disease, and swine vesicular disease. Infectious diseases on which insufficient research has been done include: African swine fever, vesicular stomatitis, enterovirus disease, parvouirus disease and leptospirosis. A problem associated with this approach is ensuring that procedures shown to be effective under experimental conditions are properly carried out under field conditions: the use of nationally accredited embryo collection teams may solve this problem. Healthy recipients and good record keeping are also critical factors in the hygienic application of ET. The health status of an embryo collected from a specific disease-free donor will not be adversely affected by damage to its ZP. Where research has shown that ZP-I embryos that have been exposed to particular pathogens are not infected or contaminated after proper washing or washing and treatment, it can be assumed that the risks of transmission of the diseases caused by these pathogens will not be increased by deliberate (micromanipulation) or accidental damage to the ZP after the washing/treatment procedures have been carried out. The risks of infectious disease transmission when embryos are produced by in vitro fertilization or blastomere transplantation to mature oocytes, followed by culture, have yet to be determined.  相似文献   

19.
牦牛是青藏高原地区的重要畜种,为牧民提供生产和生活资料.但是牦牛的繁殖力较低,通常为2年1胎或3年2胎,选育改良进展缓慢.卵母细胞体外成熟培养作为体外受精和胚胎发育必不可少的步骤,已被应用于牦牛科学研究和繁殖生产上.由于牦牛卵母细胞体外成熟能力远远低于体内,因此完善体外培养条件,提高牦牛卵母细胞体外培养的成熟率,对牦牛...  相似文献   

20.
Many efforts have been made to develop effective culture conditions for the production of bovine blastocysts. Growth hormone (GH) and glucose are known to affect in vitro embryo development. To improve in vitro culture conditions, the culture medium containing fetal calf serum (FCS) or bovine serum albumin (BSA) was supplemented with GH at various periods of development, and the effects of GH on the rate of development and the quality of the blastocysts were studied. Then, starting at the morula stage, the effect of glucose and GH on the rate of development was studied. In all experimental periods, FCS was more effective than BSA at improving the development rate and increasing the cell number of blastocysts. Adding GH to the culture medium between 18 and 48 h after fertilization (1-8 cell stage embryo) did not affect either the rate of blastulation or the cell number regardless of the serum protein (FCS or BSA). From 48 to 120 h after fertilization (5-cell to morula stage) GH increased the cell number of the blastocysts in the presence of BSA, but not in the presence of FCS. From 120 to 192 h after fertilization (morula to blastocyst stage), GH improved the developmental rate and cell number in the presence of FCS, although there was no significant difference when BSA was used instead of FCS as the serum protein. When cows were implanted with blastocysts developed in the presence of GH from the morula stage, their pregnancy rate did not differ from that of the control. Increasing the glucose concentration in the medium from 1.5 mM to 3 mM starting at the morula stage (120 h after fertilization) slightly decreased the rate of development, but on the other hand, decreasing the glucose concentration to 0 mM did not affect either the rate of development or the cell number. Also, then GH had no effect on the developmental rate or the cell number in the absence of glucose. In conclusion, when the medium was supplemented with serum, GH improved embryo development from the morula stage, but an increased concentration of glucose decreased embryo development. Furthermore, GH did not improve the pregnancy rate of blastocysts developed in vitro.  相似文献   

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