首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 15 毫秒
1.
Effect of the strain combination of the donor and recipient on production efficiency of W‐bearing sperm in mixed‐sex chimeric testes was analyzed. The combinations of the donors and recipients were White Leghorn (WL) and Rhode Island Red (RIR), and vice versa. Generated mixed‐sex chimeras that had the male phenotype at sexual maturity were classified into four groups: (1) a female WL donor and a male RIR recipient; (2) a male WL donor and a female RIR recipient; (3) a female RIR donor and a male WL recipient; (4) a male RIR donor and a female WL recipient. The mean number of W‐bearing sperm detected by in situ hybridization among 10 000 sperm observed were 147, 165, 30 and 45 in groups 1, 2, 3 and 4, respectively. The numbers in groups 1 and 2 were both significantly higher than those of groups 3 and 4 (P < 0.05). The combination of a WL donor and a RIR recipient produced W‐bearing sperm more efficiently than the reverse combination.  相似文献   

2.
The continuous production of mammalian sperm is maintained by the proliferation and differentiation of spermatogonial stem cells, which originate from primordial germ cells in the early embryo. Previously, we reported that the transplantation of fetal male gonadal tissue into the recipient testis was effective obtaining functional sperm. This transplantation technique is a promising new approach for the preservation of testicular function in a mutant animal with embryonic lethality. In the present study, we examined whether spermatogenesis from fetal male germ cells is induced under ectopic conditions in male and female recipients. Nine to 10 weeks after the transplantation of male gonads prepared from embryos at 12.5 or 16.5 days post gestation, male germ cell differentiation occurred under the skin of male and female recipient nude mice. Histological analyses revealed that grafted gonads contained haploid germ cells such as round or elongated spermatids. Furthermore, we succeeded in obtaining normal progeny by injecting the ectopically produced round spermatids into the cytoplasm of oocytes, even when the male germ cells had been generated in female recipients. These results indicate that the transplantation of fetal male gonads under the skin of recipient mice is a useful technique for obtaining functional male gametes.  相似文献   

3.
(1) Four breeding groups of Rhode Island Red and White Leghorn domestic fowl (RIR (female) x RIR (male), RIR (female) x WL (male), WL (female) x RIR (male) and WL (female) x WL (male)) were compared for fertility, hatchability, and their post-insemination sustainability, egg weight loss during incubation and uncovered yolk in abdominal cavity of dead in shell in order to understand the problems associated with the RIR breed in these respects. (2) Crossing RIR (female) with WL (male) or in reverse sex combinations did not improve fertility in comparison to pure RIR chickens and all these groups were less fertile than the pure WL. (3) Unlike fertility, hatchability in RIR improved with the change to either sex partner of the WL breed but the WL (female) x RIR (male) combination was similar to the pure WL (97.72 and 97.12%, respectively). In contrast, crossing RIR (female) with WL (male) resulted in an improvement (86.67%) as compared to pure RIR (76.67%) but still lower than the pure WL and WL (female) x RIR (male) cross. (4) Egg weight loss during incubation was more (20.16%) in pure RIR as compared to RIR (female) x WL (male) (17.13%), followed by WL (female) x RIR (male) (10.28%) and pure WL (9.57%). (5) There were more dead-in-shell embryos with yolks outside their abdominal cavity in pure RIR and their crosses as compared to pure WL breeds. (6) Fertility was sustained for longer in WL than other combinations with post-artificial insemination using constant number of spermatozoa. Fertility after a week of insemination tended to decrease more rapidly than hatchability on a fertile egg basis. (7) It is concluded that both sexes are responsible for the poor fertility in RIR but the female is responsible for poor hatchability and this poor performance is mainly due to greater egg weight loss during incubation.  相似文献   

4.
Gonadal germ cells (GGC) were collected from the gonads of 7‐ or 9‐day‐old White Leghorn chick embryos and suspended in freezing medium containing 10% dimethylsulfoxide (DMSO). The cell suspension was frozen at ?1°C/min. until the temperature reached ?80°C. Then, the cells were immersed in liquid nitrogen at ?196°C and stored for 3–4 months. Approximately 50 frozen/thawed GGC were injected into the dorsal aorta of each 2‐day‐old Rhode Island Red (RIR) embryo, from which blood was drawn before germ‐cell injection. The injected embryos were incubated until they hatched and the chicks were raised until sexually mature. On reaching sexual maturity, a progeny test was performed by mating recipient chicks with normal RIR of the opposite sex. Progenies were obtained from male germ cell recipients that were injected with germ cells collected from 7‐ and 9‐day‐old embryos. The results demonstrated that frozen/thawed GGC collected from 7‐ or 9‐day‐old fertilized eggs can be used to produce male germ‐line chimeras.  相似文献   

5.
Germ-cell transplantation has many applications in biology and animal husbandry, including investigating the complex processes of germ-cell development and differentiation, producing transgenic animals by genetically modifying germline cells, and creating broodstock systems in which a target species can be produced from a surrogate parent. The germ-cell transplantation technique was initially established in chickens using primordial germ cells (PGCs), and was subsequently extended to mice using spermatogonial stem cells. Recently, we developed the first germ-cell transplantation system in lower vertebrates using fish PGCs and spermatogonia. During mammalian germ-cell transplantation, donor spermatogonial stem cells are introduced into the seminiferous tubules of the recipient testes. By contrast, in the fish germ-cell transplantation system, donor cells are microinjected into the peritoneal cavities of newly hatched embryos; this allows the donor germ cells to migrate towards, and subsequently colonize, the recipient genital ridges. The recipient embryos have immature immune systems, so the donor germ cells can survive and even differentiate into mature gametes in their allogeneic gonads, ultimately leading to the production of normal offspring. In addition, implanted spermatogonia can successfully differentiate into sperm and eggs, respectively, in male and female recipients. The results of transplantation studies in fish are improving our understanding of the development of germ-cell systems during vertebrate evolution.  相似文献   

6.
1. The present study was conducted to elucidate the effect of soft X-ray irradiation on the migratory ability of primordial germ cells (PGCs) to the germinal ridges of chicken embryos. 2. PGCs (Barred Plymouth Rock, BPR) were isolated from embryonic blood and irradiated with soft X-rays for 1-10 min. Then, the PGCs were transfected in vitro with GFP gene by lipofection. The manipulated PGCs were transferred to recipient embryos (White Leghorn, WL) and migration to the germinal ridges was analysed by examining GFP gene expression in the gonads of recipient embryos under UV light at x40 magnifications. The expression of GFP gene was detected in all the gonads of recipient embryos examined up to 10.5 d of culture. 3. Migration of PGCs irradiated with soft X-rays to the germinal ridges was also confirmed by detecting a single nucleotide polymorphism in the D-loop region of the mitochondrial DNA of BPR and WL chickens. Freshly collected PGCs (BPR) were transferred to the bloodstream of recipient embryos (WL). The fate of the transferred donor PGCs was traced by detecting the single nucleotide polymorphism in the D-loop region of the mitochondrial DNA in BPR and WL used in this study. Transferred donor PGC-derived cells were detected in all the gonads of 17-d cultured embryos by PCR. 4. The results suggest that PGCs irradiated with soft X-rays still retain the ability to migrate to the germinal ridges of recipient embryos.  相似文献   

7.
The Japanese quail (Coturnix japonica) is a valuable bird as both an experimental animal, for a wide range of scientific disciplines, and an agricultural animal, for the production of eggs and meat. Cryopreservation of PGCs would be a feasible strategy for the conservation of both male and female fertility cells in Japanese quail. However, the effects of freeze-thaw treatment on viability, migration ability and germline transmission ability of quail PGCs still remain unclear. In the present study, male and female PGCs were isolated from the blood of 2-day-old embryos, which were cooled by slow freezing and then cryopreserved at –196 C for 77–185 days, respectively. The average recovery rate of PGCs after freeze-thawing was 47.0%. The viability of PGCs in the frozen group was significantly lower than that of the control group (P<0.05) (85.5% vs. 95.1%). Both fresh and Frozen-thawed PGCs that were intravascularly transplanted into recipient embryos migrated toward and were incorporated into recipient gonads, although the number of PGCs settled in the gonads was 48.5% lower in the frozen group than in the unfrozen control group (P<0.05). Genetic cross analysis revealed that one female and two male recipients produced live progeny derived from the frozen-thawed PGCs. The frequency of donor-derived offspring was slightly lower than that of unfrozen controls, but the difference was not significant (4.0 vs. 14.0%). These results revealed that freeze-thaw treatment causes a decrease in viability, migration ability and germline transmission ability of PGCs in quail.  相似文献   

8.
1. The present study was carried out to determine whether primordial germ cells isolated from embryonic blood can enter the bloodstream and successfully migrate to the germinal ridges of recipient embryos after transfer to stage X blastoderms, and also whether they can differentiate into blood cells, as is suggested in mice. 2. Primordial germ cells were transfected in vitro by lipofection and then transferred to stage X blastoderms. The introduced GFP gene was efficiently expressed in the gonads of 6-d incubated embryos. 3. Freshly collected primordial germ cells were transferred to stage X blastoderms. The fate of the transferred primordial germ cells was traced by detecting the single nucleotide polymorphism in the D-loop region of the mitochondrial DNA in White Leghorn and Barred Plymouth Rock chickens used in this study. The transferred donor primordial germ cell-derived cells were detected in the gonads, but not in the blood cells, of 17-d incubated embryos by PCR. 4. This procedure for primordial germ cell manipulation could provide a novel method of producing germline chimaeric chickens. 5. In conclusion, our findings indicate that primordial germ cells isolated from embryonic blood can migrate to the germinal ridges of recipient embryos after being transferred to stage X blastoderms. Although these transferred primordial germ cells differentiated into germ cells, no differentiation into blood cells was observed.  相似文献   

9.
We have revealed several unique characteristics of germ cell development using rainbow trout, including the fact that spermatogonia transplanted into the peritoneal cavity of newly hatched embryos migrate toward recipient gonads, that spermatogonia transplanted into female recipients start oogenesis and produce functional eggs and that diploid germ cells transplanted into triploid trout can complete gametogenesis. By combining these unique features of fish germ cells, we established allogeneic and xenogeneic transplantation systems for spermatogonia in several fish species. Spermatogonia isolated from the mature testes of vasa-green fluorescent protein (Gfp) transgenic rainbow trout were transplanted into the peritoneal cavity of triploid masu salmon newly hatched embryos. These spermatogonia migrated toward recipient salmon genital ridges with extending pseudopodia and were subsequently incorporated into them. We further confirmed that the donor-derived spermatogonia resumed gametogenesis and produced sperm and eggs in male and female salmon recipients, respectively. By inseminating the resulting eggs and sperm, we obtained only rainbow trout offspring in the F1 generation, suggesting that the triploid salmon recipients produced functional gametes derived only from donor trout. We further confirmed that this intra-peritoneal transplantation of germ cells is applicable to several marine fishes, which could be of benefit in the production of bluefin tuna that has a large broodstock (>100 kg) and is difficult to maintain in captivity. Gamete production of bluefin tuna could be more easily achieved by generating a surrogate species, such as mackerel, that can produce tuna gametes.  相似文献   

10.
The purpose of this study was to produce quail–duck chimeras by transferring stage X blastoderm cells and to detect the distribution of donor cells in heterogeneous embryos using PCR. Four experimental groups were made by transferring different amounts of quail blastoderm cells into duck recipients. In early embryonic stages, donor cells labeled with PKH26 fluorescent dye were observed in the head, neural tube and gonads by fluorescent microscopy. A total of 194 duck recipient embryos were injected and 93 survived to hatch. The average hatching rate was 48% (93/194); the hatching rate showed a significant difference among all the groups (P < 0.05). Sixteen somatic chimeras were obtained, 10 of which had black feathers derived from the donor quail. The PCR results showed that donor cells were distributed in various tissues and organs of the phenotypic chimeras. This is the first report on producing Japanese quail–Peking duck chimeras by transferring quail blastoderm cells into the subgerminal cavity of the duck. This technique will provide a basis for the investigation of fertilization barriers in interspecies germline chimeras and will aid conservation of endangered wild birds.  相似文献   

11.
奶牛四分胚分割研究   总被引：5，自引：1，他引：4  
用玻璃针四等分7天的奶牛胚胎为四分(1/4)胚。同一胚胎2个四分胚装回空透明带内,另2个四分胚不装带,成对非手术移给受体奶牛。两次试验共分割胚胎(晚桑椹到囊胚期)11枚,得到42个四分胚。移植受体32头,有3头妊娠。最后,一头受体生出一对同卵双胎四分胚母犊,另一头产一四分胚母犊,均由装带四分胚发育而来。还有一头受体产一四分胚公犊,是由未装带的四分胚发育得到的。试验还分割一个8天囊胚,把一个无带四分胚先放在体外培养24小时再移入受体。结果获得一头四分胚母犊。  相似文献   

12.
本试验旨在研究胚胎期大鼠性腺生长与分化的情况。选取12.5~15.5 dpc SD大鼠胚胎为研究对象,运用PCR技术进行大鼠胚胎性别鉴定,采用H-E技术对大鼠性腺分化形态进行观察。结果表明:12.5 d的鼠胚肾管已经开始形成,生殖嵴已经建立,此时仍无明显的性别分化形态;13.5 d的鼠胚开始出现性别分化的迹象,雄性的原始性索开始形成,雌性性腺分化比雄性稍晚,此期仍不易辨别出典型的卵巢特征结构;14.5 d的鼠胚性腺形态初步成型,此期性别明显分化,雄性的原始性索开始分化为实心原始生精小管,雌性胚胎中性腺分为两层,初步形成卵巢特征;15.5 d的鼠胚,雄性胚胎性腺中已经具有明显的曲精小管的雏形,雌性胚胎卵巢特征也开始明显。大鼠胚胎性腺从13.5 d胚龄时开始分化,15.5 d胚龄性腺特征明显。  相似文献   

13.
Several types of cells, including blastoderm cells, primordial germ cells, and embryonic germ cells were injected into early-stage recipient embryos to produce chimera avians and to gain insights into cell development. However, a limited number of studies of avian adult stem cells have also been conducted. This study is, to the best of our knowledge, the first to evaluate chicken bone marrow cells' (chBMC) ability to differentiate into multiple cell lineages and capability to generate chimera chicks. We induced random differentiation of chBMCs in vitro and injected immunologically selected pluripotent cells in chBMCs into the blastoderms of recipient eggs. The multipotency of BMCs from the barred Plymouth rock (BPR) was confirmed via AP staining, RT-PCR, immunocytochemistry, and FACS using specific markers, such as Oct-4 and SSEA-1, 3 and 4. Isolated chBMCs were found to be able to induce in vitro differentiation to multiple cell lineages. Approximately 5,000 chBMCs were injected into the blastoderms of white leghorn (WL) recipients and proved able to contribute to the generation of somatic chimera chicks with a frequency of 2.7% (2 of 73). Confirmation of chimerism in hatched chicks was achieved via PCR analysis using D-loop-specific primers of BPR and WL. Our study demonstrated the successful production of chimera chicks using chBMC. Therefore, we propose that the use of adult chBMCs may constitute a new possible approach to the production of chimera poultry, and may provide helpful studies in avian developmental biology.  相似文献   

14.
The objective of this study was to establish the long-term in vitro culture system for chicken gonadal primordial germ cells (gPGCs). Primitive gonads collected from 5.5-day-old chicken embryos were dissociated and explanted onto plates pre-coated with 0.1% gelatin. Each of the four different conditioned media from proliferating and mitotically inactivated chicken embryonic fibroblast (CEF) cells and murine embryonic fibroblasts (STO cells, CRL-1053, ATCC, USA), respectively, was supplemented with growth factors and used to support the growth of gPGCs. The result showed that all the conditioned media could promote the growth and colony formation of gPGCs in vitro , in particular the medium conditioned by inactivated CEF cells. The gPGC-derived colonies maintained in inactivated CEF cells-conditioned medium up to 281 days were positively stained by periodic acid Schiff reaction and antibodies specific to anti-SSEA-1, SSEA-3, SSEA-4, integrin α6 and integrin β1. Their capacities of migration via vascular system and taking up residence in the primary gonadal ridge were further demonstrated by transferring to the dorsal aorta of stage 17 recipient embryos. These results suggested that our culture system is able to maintain chicken gPGCs for long-term in vitro culture without losing their capacity to express pluripotent markers and to integrate into the gonads.  相似文献   

15.
The objective of this study was to establish a protocol for generating karyoplasts that can be used to produce somatic nuclear transferred gonadal germ cells (snt-GGCs) in domestic chickens. Karyoplasts were produced by centrifuging cultured fibroblasts from 10-day-old chick embryos at 10,000 x g in the presence of 1.0 microg/ml cytochalasin B. The number of karyoplasts was significantly (P<0.05) higher and the diameters of the karyoplasts were significantly (P<0.05) smaller when fibroblasts were centrifuged for 60 min than for 10 or 30 min. It was possible to generate snt-GGCs by electrofusion of GGCs with karyoplasts produced from cryopreserved or serum-starved fibroblasts. These results indicate that karyoplasts generated from 10-day-old chick embryos can be used to produce snt-GGCs even after cryopreservation and serum starvation of the fibroblasts.  相似文献   

16.
试验旨在研究FOXL2基因对鸡胚性腺分化的影响。本试验分为试验1组、试验2组和空白对照组（鸡胚数量分别为260、100、20枚），试验组通过胚盘下腔注射的方法分别将pLV-FOXL2慢病毒重组质粒、pLV空质粒注入胚胎期第2天的鸡胚，空白对照组不做处理并与试验组一起孵化至出雏，利用CHD1基因遗传性别鉴定的方法对出雏的雏鸡进行性别检测，分析其性腺解剖学、组织学结构变化，并利用免疫组化的方法检测性腺FOXL2和CYP19A1蛋白表达量。结果显示，试验1组遗传性别为公的23只，遗传性别为母的18只，表型性别为公的21只，表型性别为母的18只，其中有2只表型性别不典型，左侧性腺发生变化，朝卵巢结构转变；试验2组遗传性别为公的9只，遗传性别为母的12只，表型性别与遗传性别一致。阳性PCR检测结果显示，试验1组获得阳性个体10个，阳性率为24.4%（10/41）；试验2组获得阳性个体8个，阳性率为38.1%（8/21）。性腺解剖学结果显示，阳性pLV-FOXL2雄性鸡胚左侧性腺体积明显大于右侧性腺，表现膨松状态；组织切片结果显示，雄性鸡胚性腺具有典型的卵巢皮质层和髓质层结构；阳性pLV-FOXL2雌性鸡胚性腺的发育无明显变化。免疫组化结果显示，FOXL2和CYP19A1蛋白在试验1组左右侧睾丸中的表达量与空白对照组母鸡卵巢中的表达量相似，显著高于试验2组（P<0.05）。以上结果表明，FOXL2基因可能促进鸡雄性性腺的性反转，在鸡性腺分化和发育过程中发挥着重要的作用。  相似文献   

17.
The aim of this study was to investigate the effect of FOXL2 gene on gonadal differentiation in chicken embryos.This test was divided into the experiment groups 1,2 and blank control group(chicken embryos were 260,100 and 20,respectively).In the experimental group,pLV-FOXL2 lentivirus recombinant plasmids and pLV empty plasmids were injected into the chicken embryo on the second day of the embryonic stage by subpaneoidal injection.The blank control group was not treated and incubated with the experimental groups until the chick was hatched.CHD1 gene genetic sex identification method was used to detect the sex of chicks,the changes of gonadal anatomy and histological structure were analyzed,and the expression levels of FOXL2 and CYP19A1 proteins were detected by immunohistochemistry.The results showed that in the experiment group 1,there were 23 male and 18 female of genetic sex,21 male and 18 female of phenotypic sex,and two of them had atypical phenotypic gender,with changes in the left gonadal gland toward ovarian structure.The phenotypic sex was consistent with the genetic sex in experiment group 2,with 9 male and 12 female.Positive PCR results showed that 10 positive individuals were obtained in the experiment group 1,with a positive rate of 24.4% (10/41),and 8 positive individuals were obtained in the experiment group 2,with a positive rate of 38.1% (8/21).The anatomical structure of the gonad showed that the volume of the left gonad was significantly larger than that of the right gonad in the positive plV-FOXL2 male embryos.The results of tissue sections showed that the gonad of male chicken embryo had typical structure of ovarian cortex and medulla.There was no significant change in the development of gonad in female embryos with positive pLV-FOXL2.Immunohistochemical results showed that the expression levels of FOXL2 and CYP19A1 proteins in the left and right testicle of experiment group 1 were similar to that in the hen ovary of the blank control group,and were significantly higher than that in experiment group 2 (P<0.05).These results suggested that FOXL2 gene might promote the sexual inversion of chicken gonads and played an important role in the differentiation and development of chicken gonads.  相似文献   

18.
Primordial germ cells (PGCs) are embryonic precursors of germline cells with potential applications in genetic conservation, transgenic animal production and germline stem cell research. These lines of research would benefit from improved germline transmission of transplanted PGCs in chimeric chickens. We therefore evaluated the effects of pretransplant X-irradiation of recipient embryos on the efficacy of germline transmission of donor PGCs in chimeric chickens. Intact chicken eggs were exposed to X-ray doses of 3, 6 and 9 Gy (dose rate = 0.12 Gy/min) after 52 h of incubation. There was no significant difference in hatching rate between the 3-Gy-irradiated group and the nonirradiated control group (40.0 vs. 69.6%), but the hatching rate in the 6-Gy-irradiated group (28.6%) was significantly lower than in the control group (P<0.05). No embryos irradiated with 9 Gy of X-rays survived to hatching. X-irradiation significantly reduced the number of endogenous PGCs in the embryonic gonads at stage 27 in a dose-dependent manner compared with nonirradiated controls. The numbers of endogenous PGCs in the 3-, 6- and 9-Gy-irradiated groups were 21.0, 9.6 and 4.6% of the nonirradiated control numbers, respectively. Sets of 100 donor PGCs were subsequently transferred intravascularly into embryos irradiated with 3 Gy X-rays and nonirradiated control embryos. Genetic cross-test analysis revealed that the germline transmission rate in the 3-Gy-irradiated group was significantly higher than in the control group (27.5 vs. 5.6%; P<0.05). In conclusion, X-irradiation reduced the number of endogenous PGCs and increased the germline transmission of transferred PGCs in chimeric chickens.  相似文献   

19.
抑制芳香化酶活性对母鸡性腺分化和性行为的影响   总被引：2，自引：0，他引：2  
为研究雌激素在鸡性腺和性行为分化过程中的作用,本试验在受精蛋孵化第3天气室注入100μL生理盐水或芳香化酶抑制剂(AI),出雏后常规饲养到8月龄性成熟,观察其性行为的表现,检测性腺结构和血清性激素水平.结果发现,AI处理获得的性反转母鸡出现雄性第二性征和雄性交配行为,性腺形态和组织学检查结果表明其性腺得到了不同程度的反转(1)完全反转母鸡右侧性腺发育成为睾丸,而左侧性腺出现不同程度的反转.两侧性腺均出现精细管结构,管径较正常窄,发育不完整,精细管内大量分布生殖细胞,右侧性腺的间质较左侧发达;(2)不完全反转母鸡的右侧性腺退化,左侧仍为完整卵巢.血清中雌二醇(E2)含量为不完全反转母鸡＞正常母鸡＞完全反转母鸡＞正常公鸡;睾酮(T)含量为完全反转母鸡＞不完全反转母鸡＞正常公鸡＞正常母鸡,雄性交配频率与血清T/E2的比值呈正相关.以上结果表明,在性分化前用AI阻断雌激素的合成可引起雌性性腺结构和激素分泌功能及性行为雄性化,而血清T和E2含量及其比值决定了性反转母鸡雄性交配行为的频率和强度.  相似文献   

20.
Sexing chick embryos: a rapid and simple protocol   总被引：8，自引：0，他引：8  
1. Analysis of gene expression in the developing chick gonads requires the collection of male and female tissues from embryos between 3.5 d and 8.5 d of development. However, male and female chick embryos are indistinguishable by morphological examination before d 7.5 of development. 2. Sex identification of earlier embryos is only possible by molecular methods, which at present are laborious and time consuming. 3. We have devised a PCR-based sexing protocol which combines both sex specific and control reactions in a single tube assay. The assay is rapid and effective over a wide range of DNA concentrations and is tolerant of poor quality DNA. 4. Procedures are described for identifying the sex of individual embryos using either tissue samples or a small number of cells recovered from amniotic fluid.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号