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1.
早孕因子(EPF)是一种免疫抑制性的调节因子,目前普遍认为它是热激蛋白家族成员伴侣蛋白10 的同系物,是最早确认妊娠的生化标志之一,可用花环抑制试验做生物学鉴定。EPF的可用于预测早期胚胎发育情况,帮助了解妊娠母体对胚胎的识别,免疫耐受等机制。早孕因子的发现及研究在生殖生物学领域中具有非常重要的意义。  相似文献   

2.
孕牛血清中早孕因子的分离纯化   总被引:2,自引:0,他引:2  
采用DEAE-Sepharose(DEAE-琼脂糖凝胶)、CM-Sepharose(CM-琼脂糖凝胶)等离子交换层析、抗孕牛全血清IgG-Sepharose 4B亲和层析等技术,分离纯化妊娠4-5个月健康孕牛全血清中的早孕因子(EPF),用玫瑰花环抑制实验对各阶段产物EPF活性进行检测。结果表明,经层析过柱后的CM-ⅡA提取物有EPF活性。经SDS-PAGE银染显色证实它含有分子量为21、67、80KD的蛋白,实验结果支持21KD的多肽为主要EPF活性物成分。同时实验表明了亲和层析对进一步纯化EPF是可行的。  相似文献   

3.
Nature of early reproductive failure caused by bovine viral diarrhea virus   总被引:2,自引:0,他引:2  
A 2-part study was undertaken to determine the effect of bovine viral diarrhea (BVD) virus on fertilization and early development of embryos. In experiment 1, 10 seronegative cows were superovulated and artificially inseminated twice during estrus. After the second insemination, 5 of the cows received intrauterine infusion of BVD virus suspension. The other 5 cows received suspending medium only and served as controls. All 10 cows were slaughtered on day 3, and ova and embryos were collected for morphologic evaluation. A total of 49 and 52 ova and embryos were collected from the control and virus-treated cows, respectively. Among the ova and embryos collected from control cows, 81.6% were fertilized, whereas only 52% were fertilized in the virus-treated group. The statistically significant difference (P less than 0.01) indicated that the virus interferes with fertilization. In experiment 2, the protocol was identical except for slaughter on day 13. Seventy-nine ova and embryos were collected from the 6 control cows, and the 6 virus-treated cows yielded 59 ova and embryos. Of the total ova and embryos recovered on day 13, 88.6% and 50.8% were hatched and developing normally in the control and virus-treated groups, respectively. The difference was highly significant (P less than 0.001). Unfertilized ova and degenerating embryos could not be differentiated on the basis of morphologic appearance. The nearly identical percentages of unfertilized ova in experiment 1 and unhatched ova and embryos in experiment 2 strongly suggested that fertilization failure is the principal manifestation of the observed adverse effect of BVD virus infection.  相似文献   

4.
The rosette inhibition test has been used to detect an early pregnancy factor (EPF) in the serum of ewes. EPF was shown to be to be present within 72 h of mating and was still detectable after one month of gestation and in some cases after four months' gestation. The detection of EPF could be of value in the diagnosis of pregnancy in the ewe during the first month of gestation.  相似文献   

5.
Thirty nonlactating Holstein cows were superovulated to determine the effect of artificial insemination time on fertilization status and embryo quality. During the luteal phase of the estrous cycle, cows were administered 38 mg FSH-P in a 4-d descending dose regimen. Luteolysis was induced with two injections of prostaglandin on the last day of FSH-P treatment. All cows were continuously monitored for behavioral estrus using the HeatWatch estrus detection system. All cows were inseminated once with one .5-mL straw (50 x 10(6) sperm) at either 0 (n = 10), 12 (n = 10), or 24 h (n = 10) after the first standing event. The elapsed time (mean +/- SD) from the first prostaglandin dose to the first standing event was 39.4 h +/- 7.7 h. The (mean +/- SD) duration of behavioral estrus was 13.2 h +/- 4.1 h. The (mean +/- SD) number of standing events was 27 +/- 17. Five hundred twenty-nine embryos and ova were recovered nonsurgically 6 d after insemination. Fertilization rates were 29 (0 h), 60 (12 h), and 81% (24 h) (P < .01). Percentages of excellent and good, fair and poor, and degenerate embryos were not different (P > .05). Percentages of embryos with accessory sperm were 5 (0 h), 8 (12 h), and 41 (24 h) and differed between the 0 and 24 h and the 12 and 24 h inseminations (P < .01). Artificial insemination of superovulated, nonlactating Holstein cattle 24 h after onset of estrus increased fertilization rate and percentage of embryos with accessory sperm compared with insemination at 0 or 12 h after onset of estrus. Embryo quality was not affected by time of insemination.  相似文献   

6.
The developing embryo/fetus bears antigens which are foreign to the mother and it could be expected that immune rejection of the conceptus would occur. One of the reasons why the fetus is not rejected is because a depression of the maternal immune response takes place during pregnancy. Serum from pregnant animals of several species has been shown to contain a factor, early pregnancy factor (EPF), which is immunosuppressive. EPF has been detected as early as six hours after mating and its detection could aid diagnosis of early pregnancy in all species.  相似文献   

7.
The fertilizing ability of breeding boars was evaluated on the basis of an early pregnancy factor (EPF) determined in the blood serum of test sows by the method of rosette inhibition. The fertilizing ability was tested in ten boars on an insemination farm: the fertilizing potency of 41 ejaculates was evaluated from the percent conception of 105 test sows. The percent conception of test sows was evaluated from the EPF positive findings in the blood serum of these sows in the average range of 8.02 +/- 1.70 days (the range of 2 to 11 days) after insemination and from the recorded deliveries. The evaluation of the fertilizing of boars on the basis of EPF in test sows revealed in most cases the higher fertilization rate than could be found on the basis of the recorded deliveries of test sows. There was an exception to this trend: one breeding boar with a paradoxical finding of the somewhat higher percentage of deliveries recorder in test sows, in comparison with the fertilization ability according to the results of EPF. Identical results of the two criteria of fertilizing ability were recorder in another boar with a small number of tested ejaculates and test sows. The average fertilization of the whole set of the breeding boars, expressed by the average percent conception of all test sows, reached 86.67% on the basis of the EPF positive findings in 2 to 11 days after insemination, and 67.31% on the basis of recorded deliveries. These differences in fertilization are likely to be related to the share of dams and can be ascribed to embryonic mortality.  相似文献   

8.
The present study aimed to investigate the fertility of ewes artificially inseminated with three different methods using a synthetic semen extender, AndroMed. The three methods of artificial insemination (AI) were cervical AI with fresh-diluted or frozen-diluted semen at observed estrus, and an intrauterine AI with frozen-thawed semen. A total of 80 ewes were treated with a controlled internal drug release (CIDR) containing 0.3 g progesterone per device for 12 days. In Experiment 1 (26 Suffolk ewes), superovulation was induced with 20 mg follicle-stimulating hormone and 250 IU equine chorionic gonadotropin (eCG) two days and one day before CIDR removal, respectively, during the non-breeding season. In Experiment 2 (54 Suffolk and Suffolk crossbred ewes), an intramuscular injection of 500 IU eCG was administered one day before CIDR removal to synchronize estrus and ovulation during the breeding season. In Experiment 1, fresh-diluted or frozen-thawed semen was deposited into the cervical orifice after estrus detection, and an intrauterine AI with frozen-thawed semen was performed by laparoscopy at a fixed-time basis without estrus detection. Embryos were recovered by uterine flushing 6 days after AI, and the rates of recovered, fertilized (cleaved) ova and embryos at the morula or blastocyst stage were compared among the three AI methods. In Experiment 2, the pregnancy rates after the three AI methods were compared. In Experiment 1, the rates of recovered ova were not significantly different among the three AI methods (52.5-56.7%). The rate of fertilized ova (81.0%) by laparoscopic AI with frozen-thawed semen was significantly higher compared with cervical AI of fresh-diluted (25.5%) or frozen-thawed (3.5%) semen, but the rate of embryos at the morula or blastocyst stage (17.6%) was significantly lower than that of the cervical AI with fresh-diluted semen (69.2%). The rates of ewes yielding fertilized ova were not significantly different among the three groups (44.4, 11.1 and 62.5% for cervical AI with fresh-diluted and frozen-thawed semen and intrauterine AI with frozen-thawed semen). In Experiment 2, the pregnancy rate of ewes intrauterinally inseminated with frozen-thawed semen (72.2%) was significantly higher than those of ewes inseminated cervically with fresh-diluted (5.5%) or frozen-thawed (0.0%) semen. The present results showed that acceptable fertilization and pregnancy rates could be obtained by an intrauterine AI with frozen-thawed semen using a synthetic semen extender (AndroMed), but not sufficient by the cervical AI with either fresh or frozen semen.  相似文献   

9.
为探讨昆明鼠超数排卵的最佳条件,提高超排效果,比较促性腺激素使用剂量、孕马血清促性腺激素(PMSG)与人绒毛膜促性腺激素(hCG)注射间隔时间、超排小鼠所处发情周期阶段及小鼠周龄等因素对昆明鼠超数排卵结果的影响。PMSG 8IU+hCG 8IU、间隔46h~48h注射组超排效果最好;3周龄、8周龄~10周龄雌鼠较4周龄~7周龄雌鼠超排效果好,小鼠发情间期或发情前期开始超排的效果显著高于发情周期的其他时期。  相似文献   

10.
An attempt was made to induce ovulation in 19 cats during the non-breeding season by the administration of a porcine pituitary gland preparation. The dosage was 2 mg for the first day and then 1 mg for each day until estrus was induced. Studies were made to determine whether fertilization and pregnancy were possible by mating at the time of induced estrus. Estrus was induced in 89.5% (17/19) of the cats, 3-8 days after the first administration. The average number of ovulations induced by mating was 7.3 +/- 1.3 (mean +/- SE) for 16 cats (excluding one cat that failed to ovulate). The uterine horn was flushed 6-8 days after mating in 9 of the 16 ovulated cats to determine the fertilization rate. An average of 3.6 ova were recovered from 8 out of the 9 cats (including one cat from which no ovum was recovered) which gave an average recovery rate of 38.6%. Expanded blastocysts were recovered from 5 cats, while from the other 3 cats, only unfertilized ova were recovered. Pregnancy was confirmed in the other 7 cats 15-20 days after mating. In two of the 7 cats implantation was observed, but abortion occurred at 24 and 27 days of pregnancy. Plasma progesterone concentrations were lower in the estrus-induced and bred cats as compared to these in the controls, with progesterone values approaching base concentrations, approximately by day 20 in 2 cats and by day 30 in 3 cats. It was concluded that estrus could be induced in cats during the non-breeding season by administration of porcine pituitary gland preparation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

11.
Viability of maternally heat-stressed mouse zygotes in vivo and in vitro   总被引:3,自引:0,他引:3  
Mammalian preimplantation embryos are susceptible to heat stress. This present study examined how maternal heat stress affects the development of mouse zygotes in vivo and in vitro. In Experiment 1, zygotes collected from female mice that were heat‐stressed for 12 h on day 1 of pregnancy were cultured in vitro. Maternally heat‐stressed zygotes developed normally to the two‐cell stage, but the majority of embryos failed to develop into morulae or blastocysts. In Experiment 2, pregnant mice were heat‐stressed on day 1 or from day 1 to day 3 of pregnancy. The number of living fetuses on day 14 of pregnancy was lower in heat‐stressed mice than in non‐stressed mice, but the difference was significant only in successively heat‐stressed mice. These results demonstrate that maternally heat‐stressed zygotes have reduced in vitro viability, but this phenomenon does not necessarily lead to embryo loss in the maternal environment.  相似文献   

12.
《中国牛业科学》2022,48(5):17-21
[目的]为进一步研究核心群奶牛超数排卵技术影响因素。[方法]试验使用3个FSH剂量和4 个公牛精液对27头青年奶牛进行超数排卵。对供体牛胚胎生产情况和受体胚胎移植妊娠率进行统计。[结果]结果显示供体2次超排获得7.8枚平均可用胚胎显著高于1次超排获得的5.7枚平均可用胚胎(P<0.05);260,280 mg FSH超排供体获得6.0和7.7 枚平均可用胚胎显著高于300 mg FSH超排供体获得的4.6枚平均可用胚胎(P<0.05);供体使用4个公牛精液人工授精后获得的平均可用胚胎数和平均未受精卵数差异不显著(P>0.05);移植前接种疫苗的受体胚胎移植妊娠率显著降低(P<0.05)。[结论]核心群奶牛超排适宜FSH剂量为260-280 mg,使用高受精力公牛精液和对超排反应好的供体重复超排能够提高超排效率,受体移植前避免疫苗接种能够提高胚胎移植妊娠率。  相似文献   

13.
In Exp. 1, 21 first-service cattle and seven repeat-breeder cattle, averaging 4.7 infertile services, were brought into estrus and superovulated by treatment with follicle-stimulating hormone and prostaglandin F2 alpha. At insemination, semen was deposited in the greater curvature of one uterine horn, about midway between the utero-cervical junction and the utero-tubal junction. Cattle were necropsied 2 to 7 d after estrus and ova were recovered and examined. The fertilization rate for first-service cows was 74% of 362 intact ova and for repeat-breeders, 43% of 128 intact ova (P less than .001). Fertilization rate in first-service cows was 81% on the side of semen deposition and 68% on the opposite side (P less than .01); the rates in repeat-breeders were 54% and 32% (P less than .025). Differences between sides were due mostly to four cows that averaged 93% fertilization on the side of semen deposition and 19% on the opposite side. The proportion of fertilized ova with accessory sperm (17%) did not differ between sides of the reproductive tract. In Exp. 2, 60 first-service and 32 repeat-breeder cows in natural estrus had semen deposited in the uterine body or in the greater curvature of one uterine horn, either on the side of impending ovulation or on the opposite side. At necropsy, 55 ova were recovered from first-service cows, of which 42 (76%) were intact and 13 (24%) were ruptured or fragmented. Of the 42 intact ova, 41 (98%) were cleaved. From the 32 repeat-breeders, 30 ova were recovered, of which 26 (87%) were intact and 4 (13%) were ruptured; 23 of the 26 intact ova (88%) were cleaved. Site of semen deposition had no significant effect on either fertilization rate or number of accessory sperm in either type of cow. First-service cows averaged more accessory sperm (40) than did repeat-breeders (19, P less than .01). Overall results indicated that sperm deposited deep in one uterine horn fertilized ova nearly as frequently in the opposite oviduct as in the adjacent oviduct except in 14% of superovulating cattle.  相似文献   

14.
[目的]为了根据早孕因子活性的检测作为依据来判断肉牛妊娠状态.[方法]本实验采集不同孕期的肉牛的血样,同时进行了妊娠诊断,通过玫瑰花环抑制实验检测活性.[结果]实验表明,未怀孕牛和怀孕牛花环抑制滴度差异显著(P<0.05),不同孕期的早孕因子活性差异不显著.[结论]玫瑰花环抑制滴度高于8可以确认牛怀孕,低于4为未怀孕.  相似文献   

15.
The prenatal survival frequency of reciprocal F1-hybrid embryos of C57BL6/J and AKR/J mice differ remarkably (15% us 49%) indicating a strong maternal effect. Transfer of the reciprocal F1-embryos at day 4 p.c. was performed either into foster mothers of their paternal or their maternal strain in order to define the influence of the embryonic plasmatype and the maternal environment on the prenatal survival frequency of those F1-embryos. The reciprocal F1-embryos at day 4 p.c. differ according to their mother's strain in numbers of infertitized and degenerated ova, indicating a strong extrachromosomal influence on the prenatal loss, i.e. an influence rather of the embryos themselves than of the maternal environment. The number of implantation sites after transfer of the reciprocal F1-embryos differs according to the genotype of the foster mother, indicating a stronger influence of the maternal environment during implantation. Despite a small number of live fetuses after transfer, there is a significant difference of healthy fetuses according to the type of the reciprocal F1-embryos, indicating a stronger influence of the embryos themselves on the post-impluntative survival frequency. The results support the hypothesis that prenatal loss in isogenic embryos is caused to a heh degree by cytoplasmic factors of the ova .  相似文献   

16.
Ova (n=62), which were collected from slaughterhouse bovine ovaries, and embryos (n=26), which were non-surgically recovered from 11 superovulated crossbred donor cows, were frozen. The frozen ova and embryos were then thawed using two conventional thawing protocols, i.e. at 37 degrees C for 30 seconds in a water bath and at 25 degrees C for 2 minutes in air. Some 64.5% of the ova and 53.8% of the embryos thawed in the water bath and 16.1% of the ova and 7.7% of the embryos thawed in ambient air exhibited fractured zonae pellucidae. The slow thawing protocol had a lower incidence of zona damage in cryopreserved oval and embryos than the fast thawing protocol. A low pregnancy rate (12.5%) was recorded for embryos transferred with zona fracture while embryos transferred with intact zonae had a rate of 35.3%) indicating that embryos with zona damage are less viable.  相似文献   

17.
Ova (n=62), which were collected from slaughterhouse bovine ovaries, and embryos (n=26), which were non-surgically recovered from 11 superovulated crossbred donor cows, were frozen. The frozen ova and embryos were then thawed using two conventional thawing protocols, i.e. at 37 °C for 30 seconds in a water bath and at 25 °C for 2 minutes in air. Some 64.5% of the ova and 53.8% of the embryos thawed in the water bath and 16.1% of the ova and 7.7% of the embryos thawed in ambient air exhibited fractured z:onae pellucidae. The slow thawing protocol had a lower incidence of zona damage in cryopreserved oval and embryos than the fast thawing protocol. A low pregnancy rate (12.5%) was recorded for embryos transferred with zona fracture while embryos transferred with intact zonae had a rate of 35.3%) indicating that embryos with zona damage are less viable.  相似文献   

18.
In this study, we first attempted to determine whether the timing of artificial insemination affects the sex ratio of seven-day-old embryos in superovulated Holstein heifers. The superovulatory treatment consisted of eight decreasing doses of FSH for 4 days and 2 doses of PGF(2alpha) given with the last two doses of FSH. The superovulated heifers were given a GnRH analogue 48 h after the first PGF(2alpha) treatment and were artificially inseminated 48 h (n=10) or 56 h (n=8) after the first PGF(2alpha) treatment. There were no significant differences in the percentages of unfertilized ova and transferable embryos (grades 1 to 3) between the two groups. The proportions of female grade 1 embryos did not significantly differ from the expected ratio of 50:50 (49.3% at 48 h and 52.5% at 56 h). We then compared the estrous behavior and superovulatory responses of the heifers with a proportion of female embryos of 50% or less (n=7, Low group) to those of the heifers with a proportion of female embryos of more than 50% (n=9, High group). The Low group had a longer duration of estrus and a higher superovulatory response than the High group. These findings offer little encouragement for prediction of the population of female embryos collected from superovulated heifers. Further studies are necessary to evaluate to what degree maternal hormone levels are related to estrus duration and sex ratio.  相似文献   

19.
Inhalt: An 52 Kuhen aus verschiedenen ET-Programmen (n=39) sowie aus dem normalen Besamungsbetrieb (n=13) wurde geprüft, ob es auch bei dieser Spezies in der frühen Trachtigkeit im Blut zu einer vorübergehenden Thrombozytopenie kommt, wie es von O'Neill (1985) bei Mausen beobachtet wurde. Die Blutproben (Sepzialrohrchen, 5 ml mit EDTA als Antikoagulans) wurden am Tag der Besamung und an den 4 folgenden Tagen aus der V. jugularis und V. subcutanea abdominis entnommen. Die Zahl der Thrombozyten wurde aus dem Volblut im Coulter Counter, Modell S-Plus bestimmt. Nach Gruppierung der Kühe in solche mit transfertauglichen und solche rnit unbefruchteten Eizellen ergab sich bei den ersteren ein Abfall der Thrombozytenzahl bis zur 4. Probe, bei den letzteren dagegen ein vorübergehender Anstieg der Thrombozytenzaht. Dieser Unterschied erwies sich für den gesamten Untersuchungszeitraum als hochsignifikant (p ≤ 0,001). Bei den Kühen aus dem normalen Besamungsbetrieb tendier-ten die Ergebnisse nach Gruppierung der Tiere hinsichtlich ihres Trächtigkeitsstatus in die gleiche Richtung. Contents: Transitory thrombozytopenie during early pregnancy in superovulated and non-treated cows 52 cows from different ET-programs (n=39) and from the normal AI-service (n=13) were checked to see wether there is during early pregnancy a similar transitory thrombozytopenie as O'Neill has detected it in mice. Venous blood samples (5 ml EDTA as anticoagulant) were taken for 5 days, beginning from the day of AI. The number of thrombocytes was counted from whole blood in a Coulter counter, modell S plus. After grouping the tested cows in such with suitable embryos and such with unfertilized ova in the first group a drop of the thrombocytes up to the fourth sample was seen, in the second group however a transitory increase of the number of thrombocytes. This difference was highly significant (p ≤ 0,001) for the whole test periode but not from day to day. In the cows of the normal AI-service the results tended in the same direction after grouping them according their pregnancy-status.  相似文献   

20.
以含有 1.6 kb的小鼠乳清酸蛋白 (WAP)上游调序列的 p CAT- WAP和含有人 c- myc c DNA的 p WM为原始质粒 ,构建了 WAP启动子调控下的 c- myc乳腺定位表达载体 p WCS。载体用 Bgl Bam H 酶切 ,回收 3.5 kb的基因片段 WAP- c- myc- SV40 Poly A,通过显微注射方法导入 C5 7BL/ 6 J× DBA/ 2 JF1 代小鼠受精卵的雄原核内。共注射10 0 0枚卵 ,将存活的约 6 0 0枚卵分别移植至 2 9只假孕母鼠输卵管内 ,获得仔鼠 45只。PCR检测 ,阳性鼠 9只 ,South-ern blot检测 ,阳性鼠 3只 ,其中 1只母鼠 ,2只公鼠 ,在饲养过程中 ,1只母鼠意外死亡。对 2只转基因公鼠的 F1代PCR检测表明 ,仅 1只公鼠具有遗传性 ,在所生的 2 7只 F1代小鼠中有 13只为 PCR阳性。  相似文献   

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