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1.
Biodiversity is increasingly threatened by intensive agriculture, environmental pollution, extinction of natural habitats and several other factors. Several mammalian species including ungulates have disappeared or are threatened by extinction. However, ungulates play an important role both in the ecosystem and in the economy. In general, species or breeds are considered endangered if their population does not exceed 1,000 individuals. In these cases conservation programmes should be initiated in order to maintain or even increase their number. This review deals with the possibilities and limitations of assisted reproductive technologies (ART) in the conservation of ecologically valuable wild, rare and indigenous ungulates. The methods discussed here are artificial insemination, cryopreservation of semen and embryos, embryo recovery and transfer, in vitro production of embryos, as well as micromanipulation techniques including sperm injection, assisted hatching and cloning. Some of these procedures are already being exploited in the breeding of farm ungulates, but more basic information about the reproductive patterns of wild, rare and indigenous animal species is needed before the routine use of ARTs. 相似文献
2.
Rodriguez-Martinez H 《Reproduction in domestic animals》2012,47(Z1):21-26
Commercialization of animal biotechnologies, including those related to reproduction [also known as assisted reproductive techniques (ARTS)], is an increasing reality in developing countries, following the enormous flow of information around us and the increasing global commercial interests in areas where cattle production has its major assets. The present review discusses the achievements of various biotechnological tools for reproduction in cattle including semen handling for artificial insemination (AI), superovulation and embryo transfer (MOET), in vitro handling of oocytes and production of embryos, reproductive cloning and emerging technologies (sex selection, gene targeting and nuclear transfer for livestock transgenesis, genomics for marker-assisted selection, etc.). The application of these technologies for cattle breeding is critically discussed in relation to their impact in the improvement of the efficiency of dairy and beef production in developed and - particularly - in developing countries, which ultimately rule the possibilities of a competitive and sound production of food for human consumption. Despite the remarkable progress made and the punctual importance of some of the above-mentioned technologies, AI remains the most important assisted reproductive technology (ART) in developing countries. Any attempt to gain widespread of any other ART under the predominant economical conditions in developing countries ought to match the simplicity and the success of AI as a breeding tool. 相似文献
3.
Ueno S Kurome M Ueda H Tomii R Hiruma K Nagashima H 《The Journal of reproduction and development》2005,51(3):405-410
Incomplete cytoplasmic maturation of in vitro matured (IVM) oocytes has been known to cause microtubule and microfilament alterations, which may result in abnormal pronuclear formation and failed embryonic development. We examined the influences of maturation conditions on meiotic spindle morphology at metaphase of meiosis II (MII) in porcine oocytes. Porcine oocytes were matured under various conditions, i.e., in vitro or in vivo, with different amounts of cumulus cells, with or without hormonal supplements, and with various exposure durations to the hormones, to examine the effects on spindle morphology in MII oocytes by immunofluorescence under confocal laser microscopy. Interpolar spindle length (microm) and spindle area (microm2) were compared among these maturation conditions. The spindle length was significantly shorter in IVM oocytes compared to those matured in vivo. Oocytes collected from cumulus oocyte complexes (COCs), which were poor in cumulus cells, showed smaller spindle areas than those from cumulus-rich COCs. The spindle length and area were both significantly reduced in oocytes grown without hormonal supplements. When oocytes were grown with hormonal supplements for either 6 or 22 hours for the first half of culture, there was no difference in the spindle morphology between these oocytes. These results suggested that maturation conditions significantly influence morphogenesis of MII spindles in porcine oocytes. Oocytes matured in poor conditions were more likely to have a shorter spindle length (long axis) and smaller spindle areas. 相似文献
4.
利用低温生物学与人工辅助生殖技术（ART）保护生物资源,被证明是保护野生动物遗传资源的有效手段之一。野生动物的种质（卵母细胞、精子）或胚胎,相关的组织（卵巢、睾丸或附睾等）和体细胞均可以在-196℃超低温的环境下长期保持。人工辅助生殖技术除低温生物学技术外,还包括：人工授精技术;卵母细胞的体外成熟技术;体外受精技术以及胚胎移植;产前诊断等众多复杂的技术。但是,应用于野生动物的低温生物学和ART与应用与经济动物和实验动物时有很大差异,特别是某些需保种的珍稀或濒危野生动物数量有限,野生动物冷冻保种时有许多技术困难急待克服。例如：野生动物种质冷冻样品的采集问题;各种野生动物冷冻胚胎和冷冻精子时可能采取的最佳冷冻保护程序及不同的冷冻保护剂。特别是如何选取适当的野生动物受体成为制约其发展的一个瓶颈。 相似文献
5.
犬卵母细胞体外成熟及其体外受精研究进展 总被引：1，自引：0，他引：1
犬科动物胚胎对于改进犬科珍贵物种及保护濒危犬种十分重要,因此对犬科动物体外受精(IVF)以及辅助生殖(ART)的研究逐渐变得必要.通过体外受精和核移植已经成功获得能够发育的犬科动物胚胎,克隆的犬胚胎移植到受体母犬能成功产仔,但是这一技术的效率仍然很低.主要原因是犬科动物胚胎在体外发育能力很低.犬卵母细胞早期发育和其他动物不同,犬卵巢排出的卵母细胞处于生发泡(GV)期,在输卵管中恢复减数分裂.犬卵母细胞核难以观测并且不容易确定排卵时间,所以很难确定精子入卵的确切时间,并且多精受精的情况时常发生.回顾犬卵母细胞体外成熟(IVM)和体外受精取得的进展,对于提高其胚胎生产效率很有必要. 相似文献
6.
Chian RC Kuwayama M Tan L Tan J Kato O Nagai T 《The Journal of reproduction and development》2004,50(6):685-696
Improving pregnancy rates associated with the use of cryopreserved human oocytes would be an important advance in human assisted reproductive technology (ART). Vitrification allows glasslike solidification of a solution without ice crystal formation in the living cells. We have attempted to improve the survival rates of oocytes by a vitrification technique using bovine models. In vitro matured oocytes with or without cumulus cells were vitrified with either 15.0% (v/v) ethylene glycol (EG) + 15% (v/v) dimethylsulfoxide (DMSO) + 0.5 M sucrose or 15% (v/v) EG + 15% (v/v) 1,2-propanediol (PROH) + 0.5 M sucrose, using 'Cryotop' or 'thin plastic sticker', respectively. The oocyte survival rates after vitrifying-warming, and the capacity for fertilization and embryonic development were examined in vitro. The rate of embryonic development to blastocyst was significantly higher (P<0.05) in the oocytes vitrified with 15% (v/v) EG + 15% (v/v) PROH + 0.5 M sucrose than in the oocytes vitrified with 15% (v/v) EG + 15% (v/v) DMSO + 0.5 M sucrose (7.4% +/- 4.1 vs. 1.7% +/- 3.0, respectively). Oocytes vitrified without cumulus cells had a higher survival rate after thawing and a superior embryonic developmental capacity compared with oocytes vitrified with cumulus cells. Prolonged pre-incubation time after thawing adversely affected the rates of embryonic cleavage and development. These results indicate that in vitro matured bovine oocytes can be vitrified successfully with the mixture of the cryoprotectants, EG + PROH, the absence of cumulus cells for vitrification does not affect oocyte survival rate after warming, and vitrified and warmed oocytes do not require pre-incubation before in vitro fertilization. 相似文献
7.
Hiroshi SUZUKI Hiroyuki WATANABE Yasuyuki ABE 《The Journal of reproduction and development》2022,68(1):1
Assisted reproductive techniques (ARTs), such as artificial insemination, in vitro fertilization, and cryopreservation of gametes/zygotes, have been developed to improve breeding and reproduction of livestock, and for the treatment of human infertility. Their widespread use has contributed to improvements in human health and welfare. However, in dogs, only artificial insemination using frozen semen is readily available as an ART to improve breeding and control genetic diversity. A recent priority in sperm cryopreservation is the development of alternatives to egg yolk, which is widely used as a component of the sperm extender. Egg yolk can vary in composition among batches and is prone to contamination by animal pathogens. The latter can be a problem for international exchange of cryopreserved semen. Low-density lipoprotein and skim milk are promising candidates for use as extenders, to ensure fertility after artificial insemination. Although not tested for its effects on fertility following artificial insemination, polyvinyl alcohol may also be a useful alternative to egg yolk as an extender. The development of cryopreservation techniques for canine embryos lags behind that for other mammals, including humans. However, given the success of non-surgical embryo transfer in 2011, studies have sought to refine this approach for practical use. Research on sperm cryopreservation has yielded satisfactory results. However, investigation of other approaches, such as cryopreservation of oocytes and gonadal tissues, remains insufficient. Techniques for the efficient induction of estrus may aid in the development of successful canine ARTs. 相似文献
8.
卵巢组织玻璃化冷冻可替代直接冷冻卵母细胞或胚胎。玻璃化冷冻卵巢组织在辅助生殖上具有优越性。它无需控制供体的生殖周期 ,也无需取出卵泡。同样这一技术可用于保存濒危动物或受意外伤害的人或动物的卵母细胞 ;可为性成熟前失去生殖能力的动物或人提供生殖保险以及增加卵母细胞的来源 ;可用于建立生殖细胞 (卵母细胞 )的冷冻库。而传统的冷冻技术存在很多弊端。文章综述了玻璃化冷冻卵巢组织的研究背景和现状 ,并指出了其广阔的应用前景 相似文献
9.
Patrycja Mrowiec Monika Bugno-Poniewierska Wiesława Młodawska 《Reproduction in domestic animals》2021,56(2):199-207
Taking into account the latest Red List of the International Union for Conservation of Nature in which 25% of all mammals are threatened with extinction, somatic cell nuclear transfer (SCNT) could be a beneficial tool and holds a lot of potential for aiding the conservation of endangered, exotic or even extinct animal species if somatic cells of such animals are available. In the case of shortage and sparse amount of wild animal oocytes, interspecies somatic cell nuclear transfer (iSCNT), where the recipient ooplasm and donor nucleus are derived from different species, is the alternative SCNT technique. The successful application of iSCNT, resulting in the production of live offspring, was confirmed in several combination of closely related species. When nucleus donor cells and recipient oocytes have been used in many other combinations, very often with a very distant taxonomical relation iSCNT resulted only in the very early stages of cloned embryo development. Problems encountered during iSCNT related to mitochondrial DNA (mtDNA)/genomic DNA incompatibility, mtDNA heteroplasmy, embryonic genome activation of the donor nucleus by the recipient oocyte and availability of suitable foster mothers for iSCNT embryos. Implementing assisted reproductive technologies, including iSCNT, to conservation programmes also raises concerns that the production of genetically identical populations might cause problems with inbreeding. The article aims at presenting achievements, limitations and perspectives of iSCNT in maintaining animal biodiversity. 相似文献
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11.
To obtain insights into the cytoplasmic maturation status of cat oocytes recovered from cat ovaries following hormone treatment, we first examined microtubule and microfilament assembly in cat oocytes recovered from hormone-treated ovaries at various stages of maturation. Additionally, we determined the alteration of spindle and microfilament assembly, as well as mitogen-activated protein kinase (MAPK) activity, in cat oocytes at 0, 6, 12 and 18 h of further maturation in vitro. We then looked at pronuclear formation and cleavage of these oocytes following parthenogenetic activation. Similar to other species, microtubules are present in germinal vesicle (GV) stage cat oocytes, and following GV breakdown, microtubules encompassed condensed chromatin particles to form the meiotic metaphase spindle. Microfilaments were located in the cortex and around the GV. A microfilament-rich area, in which the chromatin is located, was observed in the oocytes during meiotic maturation. Maturation rates in aged oocytes (cultured for 18 h) were increased when compared with that in relatively fresh oocytes (<12 h culture), and the number of oocytes with abnormal spindle shapes was also increased in aged oocytes. Furthermore, in aged oocytes, the incidence of the metaphase plate observed outside the thick microfilament domain was higher compared with that of young oocytes, and this seemed to result in an increase in the number of oocytes with two pronuclei and one polar body following activation. Western blot analysis revealed a decrease in MAPK activity in aged cat oocytes. Taken collectively, these results suggest that the optimum time for improved cytoplasmic maturation is <12 h in cat oocytes recovered from hormone-treated ovaries. 相似文献
12.
《畜牧与生物技术杂志(英文版)》2021,(3)
Background: In vitro embryo production(IVP) and embryo transfer(ET) are two very common assisted reproductive technologies(ART) in human and cattle. However, in pig, the combination of either procedures, or even their use separately, is still considered suboptimal due to the low efficiency of IVP plus the difficulty of performing ET in the long and contorted uterus of the sow. In addition, the potential impact of these two ART on the health of the offspring is unknown. We investigated here if the use of a modified IVP system, with natural reproductive fluids(RF) as supplements to the culture media, combined with a minimally invasive surgery to perform ET, affects the output of the own IVP system as well as the reproductive performance of the mother and placental molecular traits.Results: The blastocyst rates obtained by both in vitro systems, conventional(C-IVP) and modified(RF-IVP), were similar.Pregnancy and farrowing rates were also similar. However, when compared to in vivo control(artificial insemination, AI),litter sizes of both IVP groups were lower, while placental efficiency was higher in AI than in RF-IVP. Gene expression studies revealed aberrant expression levels for PEG3 and LUM in placental tissue for C-IVP group when compared to AI,but not for RF-IVP group.Conclusions: The use of reproductive fluids as additives for the culture media in pig IVP does not improve reproductive performance of recipient mothers but could mitigate the impact of artificial procedures in the offspring. 相似文献
13.
H Naoi B Agung NWK Karja P Wongsrikeao R Shimizu M Taniguchi T Otoi 《Reproduction in domestic animals》2008,43(2):157-161
This study was conducted to examine the effects of the reproductive cycle of donor cat on the quality of oocytes at recovery and developmental competence of oocytes after in vitro fertilization (IVF) and somatic cell nuclear transfer (NT). Based on the presence or absence of follicles and corpora lutea, the ovarian pairs collected were classified into inactive, follicular or luteal stages. After collection of oocytes, the oocytes were classified into four grades according to the morphological condition of oocyte cytoplasm and cumulus cells. A total of 16 558 oocytes were obtained from 198 ovarian pairs. The total mean numbers of oocytes and the mean numbers of oocytes with high quality (grade I) were significantly higher in ovarian pairs at the inactive stage (111.1 and 19.0 oocytes, respectively) than in ovarian pairs at the follicular stage (67.1 and 11.4 oocytes, respectively). A significant difference in the proportions of oocytes with grade I out of the total examined oocytes was observed between the follicular and luteal stages of ovaries (14.9% vs 20.2%, p < 0.05). The proportions of IVF embryos cleaved and developed to blastocysts significantly decreased with decreased quality of oocytes at recovery, irrespective of the reproductive status of ovaries. Moreover, there were no significant differences in the proportions of cleavage and development to the blastocyst stage of IVF and NT embryos among three oestrous stages of ovaries. These results indicate that the reproductive cycle stage of donor cat ovaries has no apparent effects on the in vitro development of oocytes after IVF and NT, but the quality of oocytes at recovery influences the development of IVF embryos. 相似文献
14.
Anzai M Nishiwaki M Yanagi M Nakashima T Kaneko T Taguchi Y Tokoro M Shin SW Mitani T Kato H Matsumoto K Nakagata N Iritani A 《The Journal of reproduction and development》2006,52(5):601-606
Development of assisted reproductive technologies is necessary to obtain fertilized oocytes in a subfertile transgenic mouse strain. Here, we showed the application of laser-assisted drilling of the zona pellucida to in vitro fertilization of cryopreserved mouse oocytes with sperm from subfertile transgenic mice (C57BL/6N-Tg(UCP/FAD2)U8 strain). After cryopreservation by vitrification, the recovery and survival rates of the zona-drilled mouse oocytes were 97% (97/100) and 94% (91/97), respectively. In vitro fertilization of the cryopreserved zona-drilled mouse oocytes with sperm from the subfertile transgenic mice was greatly facilitated (60%, 55/91) compared to that of the cryopreserved zona-intact mouse oocytes (11%, 81/768). In vitro fertilized embryos that developed to the 2-cell stage were again cryopreserved by vitrification, and after warming they were transferred into recipient females. Subsequently, six viable offspring were delivered, and all were confirmed to be transgenic mice. These results indicate that laser-assisted zona drilling of oocytes combined with cryopreservation by vitrification may be a useful approach for large-scale production of in vitro fertilized embryos for managing transgenic mouse strains with reproductive disabilities such as subfertile sperm. 相似文献
15.
One-carbon metabolism (OCM) can be seen as integrated metabolic pathways centered on the metabolism of two nutritional substances, folate and methionine. Mammalian oocytes and preimplantation embryos express almost all enzymes that participate in OCM, suggesting that they can independently metabolize OCM nutrients. A deficiency or excess of OCM nutrients and their metabolites during in vitro culture affects preimplantation development of mammalian embryos. Recent in vivo studies have demonstrated that specific OCM dietary interventions during the periconceptional (mainly oocyte growth and preimplantation) period can cause epigenetic alterations in DNA of offspring and program the long-term consequences in their health in adulthood. The epigenetic processes are likely to be implicated in the effects of OCM nutrients; however, understanding their effects at the level of specific genes and their implications in assisted reproductive technology will require further investigations. 相似文献
16.
Chappaz E Albornoz MS Campos D Che L Palin MF Murphy BD Bordignon V 《Domestic animal endocrinology》2008,35(2):198-207
Recent studies have shown that factors from adipose tissue influence and regulate the reproductive system. Hormones such as leptin and resistin are now known to regulate several reproductive processes. Adiponectin is the most abundant protein secreted by adipose tissue, and its circulating concentration is inversely related to adiposity and body mass index. Little is known about the involvement of adiponectin in reproduction. In the present study, the effect of recombinant adiponectin on the meiotic maturation and early embryo development in vitro was investigated, using porcine oocytes. Adiponectin receptors, AdipoR1 and AdipoR2, were found to be expressed in porcine oocytes and cumulus cells of both small and large follicles. Both AdipoR1 and AdipoR2 were immunolocalized to cumulus-oocyte complexes (COCs), oocytes, and early developing embryos. When included in oocyte maturation medium for 46 h, adiponectin significantly decreased the frequency of meiotic immature oocytes derived from large follicles (3-6 mm) but not from small follicles (<3mm). From studies of oocytes matured in the presence of adiponectin and mitogen-activated protein kinase (MAPK) pathway inhibitors MEK1 (PD98059), MEK1/2 (U0126), and p38MAPK (SB203580) it was concluded that adiponectin enhances oocyte maturation thought the p38MAPK pathway. Finally, a superior rate of embryo development to the blastocyst stage was achieved by embryos cultured in the presence of adiponectin. These results indicate that adiponectin has a positive effect on the meiotic maturation and in vitro embryo development of porcine oocytes and suggests a physiological role for this adipokine in early development in mammals. 相似文献
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18.
Carnivora is one of the most species-rich order of Mammalia. Some species, e.g. domestic cats, dogs and ferrets, are among the most popular pets; others, such as minks and farmed foxes, have economic value for the fur breeding industry. Still others, such as tigers, bears and other top predators, have great impact on the health of natural ecosystems. Most if not all Carnivora species have great cultural and aesthetic importance for man. There are enormous differences between mammalian species in reproductive physiology, and it is not surprising that reproductive technologies can be used with high efficiency with some animal groups, e.g. most farm animals and laboratory rodents, but are very laborious when used with Carnivora species, which often possess unique reproductive traits. The efficiency of assisted reproductive technology (ART) applied to semi-domestic, non-domestic and especially to endangered species of Carnivora remains extremely low in most cases, and often the first positive result reported is the only instance when ART has been successful with that species. Although there are approximately 270 species in the Carnivora order, to the best of our knowledge, successful published attempts to apply ART have been reported for only four families: Mustelidae, Felidae, Canidae and Ursidae. The main achievements in ART, embryo technology in particular, for these families of Carnivora, together with challenges and problems, are reviewed in the relevant sections. 相似文献
19.
Roles of microtubules and microfilaments in spindle movements during rat oocyte meiosis 总被引：1，自引：0，他引：1
Ai JS Wang Q Li M Shi LH Ola SI Xiong B Yin S Chen DY Sun QY 《The Journal of reproduction and development》2008,54(5):391-396
Spindle movements, including spindle migration from the center to the cortex of oocytes during first meiosis and spindle rotation during second meiosis, are required for asymmetric meiotic divisions in many species. However, little is currently known in relation to the rat oocyte. To explore how spindles move and the mechanism controlling spindle movements in rat oocytes, we observed the spindle dynamics during the two meiotic divisions in the rat oocyte by confocal microscopy. Drugs that depolymerize microtubules or microfilaments were employed to further determine the roles of these two cytoskeletons in spindle movements. The results showed that peripheral spindle migration took place during first meiosis and spindle rotation took place during second meiosis in the rat oocytes. Microfilament inhibitor inhibited both spindle migration and spindle rotation, and depolymerization of microtubules inhibited spindle rotation. Severe depolymerization of microtubules inhibited spindle migration, while migration was achieved by partial but not complete depolymerization of microtubules. We thus conclude that microfilaments are important for both spindle migration and spindle rotation and that spindle microtubules are essential for spindle movements in rat oocytes. 相似文献
20.
Agnieszka Nowak Joanna Kochan Ewa Świętek Barbara Kij Sylwia Prochowska Wojciech Witarski Monika Bugno-Poniewierska Wojciech Niżański 《Reproduction in domestic animals》2020,55(8):992-997
The aim of this study was to evaluate the applicability of the Cryotech technique for the vitrification of domestic cat (Felis catus) oocytes, as a model for other feline species threatened with extinction. This technique, in which oocytes are stored in a minimal volume of medium, is already widely used in human assisted reproductive technology. In the first part of this study, a viability test (EtBr/FDA) was used to evaluate the toxicity of the vitrification media (solutions). After IVM, oocytes were placed in vitrification and warming solutions according to the manufacturer's procedure, with or without exposure to liquid nitrogen. The solutions and the vitrification procedure each caused a reduction in oocyte viability, with survival rates of 71.4% in oocytes exposed to the Cryotech media (without cooling in liquid nitrogen), and 62% in oocytes that were vitrified. In the second part of the experiment, parthenogenetic activation was used to evaluate the developmental potential of oocytes previously vitrified using the Cryotech method. After warming, the oocytes were activated using a combination of 0.7 µM ionomycin in TCM 199 medium (5 min) followed by 2 mM 6-DMAP in TCM 199 supplemented with 10% FBS (3 hr), then cultured and evaluated every 24 hr for parthenogenetic cleavage. In the experimental group, 23/50 (46%) cleaved embryos were obtained. Domestic cat oocytes, vitrified by the Cryotech method, are characterized by high survival rates. However, it is necessary to improve the technique to increase the developmental competence of embryos obtained from vitrified oocytes. 相似文献