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1.
A total of 169 pregnant cats presented for ovariohysterectomy were examined for the number of corpora lutea (CL) and the number of fetuses per uterine horn. The implantation rate and the frequency of occurrence of transuterine migration of embryos were calculated. The average number of CL was 5.6 +/- 1.9 (mean +/- SD; range, 2-11), the average number of fetuses was 4.5 +/- 1.4 (range, 1-8) and the average implantation rate was 84 +/- 20%. Transuterine migration occurred in 69/169 cats (40.8%). In animals with a 100% implantation rate, transuterine migration occurred in 50/84 cats (59.5%). The number of embryos that migrated ranged from 1-3 per animal and embryos moved from the uterine horn ipsilateral to the ovary with the larger number of CL in 66/69 cats (95.7%). As a result of transuterine migration, the difference in the number of fetuses between uterine horns as compared with the difference in the number of CL between ovaries was smaller in 54 casts (78.3%), unchanged in 8 cats (11.6%) and larger in 7 cats (10.1%). These results indicate that cats tend to equalize the number of fetuses between uterine horns by transuterine migration of embryos.  相似文献   

2.
Studies were made on the number of sperms required for fertilization of ova ovulated from the bilateral ovaries in bitches. The experiment was carried out with 44 female beagles, which were divided into four groups of seven to eleven bitches each. The four groups were inseminated with 40 X 10(6) sperms/0.2 ml, 20 X 10(6) sperms/0.1 ml, 10 X 10(6) sperms/0.1 ml, and 3-5 X 10(6) sperms/0.1 ml, respectively. All the bitches were laparotomized at an optimum time for mating and inseminated at the tip of the horn of an unilateral uterus. In the four groups conception took place at a rate of 7/7, 8/8, 10/11, and 2/7, respectively. The number of puppies exceeded the number of ova ovulated on the inseminated side at a rate of 5/7, 6/8, 0/10, and 0/2 in the four groups, respectively. Therefore, it was clarified that when more than 20 X 10(6) sperms/0.1 ml were inseminated in the ipsilateral uterine horn, ova ovulated on the contralateral side were fertilized also. Then a unilateral ovary was ovariectomized in 11 bitches, which were inseminated with 10 X 10(6) sperms/0.1 ml in the ipsilateral uterine horn. As a result, only one bitch became conceptive and gave birth to only one puppy. From these results, it was considered that 10 X 10(6) sperms/0.1 ml may be most adequate for the ova on the side of insemination alone to be fertilized.  相似文献   

3.
Unilateral intrauterine horn insemination (UIUI) was carried out in cats, and we investigated the fertilization rate of ova ovulated from the contralateral ovary. Various numbers of sperm were used to inseminate the uterine horn on the side where ovulation was inhibited. The rates of conception were 1/11 (9.1%), 2/11 (18.2%), and 5/7 (71.4%) in the 2 x 10(6), 4 x 10(6), and 8 x 10 (6) groups, respectively. Furthermore, the fertilization rate was 70.7% in the 8 x 10(6) group. Thus, ova ovulated from the contralateral ovary were not fertilized or the fertilization rate was low in some cats even when UIUI was performed with a large number of sperm.  相似文献   

4.
Deep intrauterine insemination in pigs allows sperm deposition only into one uterine horn, but bilateral fertilization of oocytes occurs. How the sperm reach the contralateral oviduct remains disputable. The aim of this experiment was to study possible transperitoneal and/or transuterine sperm migration ways. Follicle growth and ovulation were induced in 24 peripubertal gilts with eCG and hCG 72 h after eCG. Endoscopic intrauterine insemination (IUI) was performed 32 h after hCG with 20 ml of extended semen (60 × 10(6) spermatozoa) as follows: Group CONTROL (n=8) received IUI into the right horn, and the left horn served as non-treated control; Group LIGATURE (n=8) received IUI into the right horn, and the left horn was closed by endoscopic double ligature close to the bifurcation; Group INTRAPERITONEAL (IPI; n=8) received IUI into the right uterine horn, the left horn was closed by double ligature and semen was deposited intraperitoneally at the surface of the left ovary. Genital tracts were removed 65-66 h after hCG, the oviducts were flushed and ova (n=299) were analyzed for fertilization and cleavage. Furthermore, the accessory spermatozoa count/oocyte was graded as 0, without spermatozoa, 1, <5 spermatozoa, 2, 5-50 spermatozoa, 3, 50-100 spermatozoa and 4, >100 spermatozoa. The results indicate that low dose IUI into one horn provides a lower grade of accessory spermatozoa in the contra-lateral side (1.6 vs. 2.8). No spermatozoa were found in ova flushed from oviducts of the ligated uterine horn, even after intraperitoneal insemination (P<0.05), and no fertilization occurred, respectively. Our results clearly indicate that after low dose IUI into one uterine horn, spermatozoa reach the contralateral oviduct via transuterine migration.  相似文献   

5.
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   

6.
The effect upon the reproduction of total resection of the oviductal isthmus, including the uterotubal and ampullary-isthmus junctions followed by end-to-end ampullo-cornual anastomosis was studied in pigs. Normal cycling gifts of proved fertility were submitted to bilateral isthmus deletion (Group I). Other gilts were submitted only to unilateral isthmic resection, while their contralateral medial isthmus was transversally cut and reanastomosed (Group II). A significantly lower nidation index was obtained after bilateral isthmic resection. The gilts in Group I which did not become pregnant and those in Group II were successfully mated during forthcoming standing oestruses, and were in association to that slaughtered on days 3, 4, or 5 of the cycle, and the characteristics and location of ova were determined. Spermatozoa fertilized the ova, and those cleaved normally in the isthmic-resected tube as well as in the sham-operated oviducts. The isthmic-resected oviduct, however, did not transport cleaved ova into the uterus at the time expected as normal. The findings suggest that the fertilized pig ova cannot reach the uterus at the normal expected time in case of total absence of the isthmic part of the oviduct, resulting in impaired fertility.  相似文献   

7.
This study aimed to compare the efficiency of non‐surgical embryo transfer (ET) using a newly developed catheter, which enables transferring embryos into a proximal site of the uterus (mostly uterine body), and surgical ET of vitrified porcine embryos. In Experiment 1, the catheter was inserted into 12 gilts, with each half of the group allocated to skilled or novice operators. The time required for insertion into the uterus did not differ between skilled and novice operators (4 min 9 s and 4 min 6 s, respectively). In Experiment 2, 12 gilts were used as recipients for non‐surgical and surgical ET with vitrified embryos (n = 6, each). There was no significant difference in the rate of piglet production based on the number of transferred embryos between surgical and non‐surgical ET (25.8% vs. 15.4%, p = .098). The results suggest that non‐surgical ET catheter allowed for easy insertion and transfer of embryos without special training. Although the catheter is effective for deposition of embryos into the proximal site of uterus, the efficiency of piglet production is not enhanced compared with surgical ET. The ET method using this catheter, being labor‐saving and less‐invasive, may contribute to the improvement of ET in pigs.  相似文献   

8.
An experiment was conducted to determine whether balancing dietary crude protein for optimal rumen degradability would improve fertilization rate and quality of ova in lactating dairy cows. Thirty-eight Holstein cows in early lactation were fed 1 of 2 diets formulated to be isocaloric and isonitrogenous, containing 16% crude protein. Diet 1 contained 73% rumen degradable intake protein, whereas diet 2 contained 64% rumen degradable intake protein. The cows were induced to superovulate and were inseminated, and ova were recovered nonsurgically on postbreeding day 7. Ova were counted and classified as fertilized or unfertilized. Fertilized ova were scored as excellent, good, fair, poor, or degenerate. Unfertilized ova and poor and degenerate embryos were considered to be nontransferable ova and excellent, good, and fair embryos were considered to be transferable ova. There were no differences for mean number of fertilized, unfertilized, transferable, or nontransferable ova recovered from cows fed the 2 diets (P greater than 0.10). Mean percentage of fertilized ova recovered from cows was greater (P less than 0.05) in those fed diet 2, compared with diet 1. Mean percentage of transferable ova recovered from cows tended to be greater (P = 0.06) in those fed diet 2, compared with diet 1. More cows failed to yield transferable ova (P less than 0.05) when fed diet 1, compared with diet 2. Fertilization failure or early degeneration of embryos may occur in cows fed excess rumen degradable protein.  相似文献   

9.
This study was conducted to establish a new approach for in vivo culture of in vitro produced embryos in the bovine oviduct by transvaginal endoscopy. Embryos were in vitro matured, fertilized and cultured for 1-4 days and assigned to groups consisting of 10-30 embryos. Embryos were transferred unilaterally into oviducts of 24 heifers by the means of transvaginal endoscopy. After 3-6 days of in vivo incubation embryos were re-collected. Experiment I aimed to evaluate the capability of embryos to migrate to the uterus. The uterine horns of four animals were flushed first, followed by a combined flushing of both oviducts and uterine horns resulting in collection rates of 31 and 34%, respectively. In experiment II, the transfer of embryos into the oviduct close to ovulation (day 1-2--experiment IIA) or at a more advanced cyclic stage (day 3--experiment IIB) succeeded in the collection of 46 and 34% of the transferred complexes, of which 13 and 37% showed the blastocyst stage. This is the first report of successful recovery of transferable blastocysts by transvaginal endoscopy after tubal in vivo culture in the homologous species of originally in vitro produced embryos.  相似文献   

10.
The capability of pregnant mare serum (PMS) and human chorionic gonadotropin (HCG) to induce estrus and ovulation was tested in mature, anestrous bitches. The PMS was given for 10 consecutive days in 1 of 3 regimens: 500 IU/day (experiment 1), 250 IU/day (experiment 2), or 20 IU/kg/day (experiment 3). The HCG was given as a single 500-IU dose on experimental day 10. Controls were given saline solution. Vaginal smears were collected on days 1, 3, 5, 7, 9, and 12 by jugular venipuncture, and the plasma was assayed for progesterone concentration by radioimmunoassay. On day 13, the bitches were euthanatized, ova were flushed from the uterine tubes (oviducts), and the ovaries were collected and prepared for microscopic examination. Fourteen of 25 bitches treated with PMS and HCG showed estrus and ovulated. Proestrus (vaginal bleeding) commenced between experimental days 7 and 10. Estrus commenced on day 9 or 10. Progesterone increased from approximately 1 ng/ml on day 1 to more than 6 ng/ml on day 12. Numbers of ovulation sites on both ovaries were 4.7 +/- 1.1 and 4.6 +/- 0.5 (mean +/- SEM) in those given the daily doses of 500 and 250 IU of PMS and 9.8 +/- 1.5 in experiment 3 bitches. Eleven hormone-treated dogs and 7 saline-treated dogs did not show any detectable response. Neither cystic nor unovulated, luteinized follicles appeared on the ovaries.  相似文献   

11.
Artificial insemination was carried out by injecting semen into the upper part of the left uterine horn in rabbits with a duplex uterus. Ovulation was then induced by administration of hCG. As a result, implanted fetuses were observed not only in the left uterine horn but also in the right uterine horn. However, when similar insemination was carried out after ligation of the right utero-tubal junction, fertilization did not occur in the right oviduct. From these finding, we conclude that some of the spermatozoa injected into the left uterine horn was discharged into the vagina, entered the right uterine cervical canal, and reached the right oviduct to fertilize the ova.  相似文献   

12.
The effects of pregnant mare serum gonadotrophin (PMSG) dose and PMSG antiserum on superovulation in crossbred beef cows were studied. In experiment I, three groups were treated with 1200, 2400 or 3600 IU of PMSG and 48 h later with prostaglandin (PGF). The mean numbers of corpora lutea (CL), unovulated follicles, and total ova/embryos collected increased as the PMSG dose increased. The percent of fertilized ova and transferable embryos was lowest in the highest dose group (p < 0.05). In experiment II, all cows received 2500 IU of PMSG; groups 1 and 2 were treated with sheep anti-PMSG serum at 48 h or 60 h after PGF; group 3 cows were PMSG-only controls. The number of CL was lowest and the number of unovulated follicles highest in the PMSG-only group (p < 0.05). The number of CL was higher in group 2 (anti-PMSG at 60 h) than in the control group, with the anti-PMSG at 48 h not different from the other groups. Numbers of total ova/embryos, fertilized ova, and transferable embryos were higher (p < 0.05) in both antiserum-treated groups relative to the PMSG-only group. We conclude that superovulation of beef cows with PMSG and treatment with PMSG antiserum will induce a higher superovulatory response and will result in higher CL numbers and fewer unovulated follicles. Further, the variability in the superovulatory response to PMSG treatment was still evident when PMSG antiserum was administered.  相似文献   

13.
Total 240 flushings of superovulated donor cows were examined after double sedimentation. Altogether 2,810 ova and embryos, i.e. average of 11.7 per donor, including 9.0 (76.97%) transferable embryos, were obtained after the first sedimentation. The sedimentation was carried out separately for the respective uterine horns. The second sedimentation, which was carried out in the flushing from both uterine horns simultaneously, yielded ova and embryos in 82.9% (199/240) of the cases. Total 679 ova and embryos were found, i.e. 3.41 per donor, including 2.61 (76.58%) transferable embryos per donor. The increase of the yield of total ova and embryos, and transferable embryos, was 2.82 and 2.16 (24:16 and 24.04%) respectively after the second sedimentation. Altogether 3.489 total ova and embryos were obtained from 240 donors. The average embryo yield was 14.53 per donor with 76.89% (11.17) transferable embryos. The embryo yield/corpora lutea ratio was at the number of corpora lutea 12.04 on the average 120.68%. It is concluded that the second sedimentation of the flushing provides for the release of a part of the embryos for the mucous and cell aggregations, which density is usually lower. The effect of the second sedimentation is considerable, because as much as 24% of the total number of transferable embryos can be saved. The total efficiency of superovulation may be considerably decreased if no attention is paid to the above mentioned facts.  相似文献   

14.
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   

15.
Tissue strips from the ovary, (uterine tube), and oviduct, and uterus of pregnant and nonpregnant cows were tested for their contractile response to prostaglandin F2 alpha (PGF2 alpha). When 2.1 x 10(-6)M PGF2 alpha was added to the uterine strips, tension of tissues from pregnant cows increased sharply; however, tension in tissues from nonpregnant cows only increased moderately. Similar concentrations failed to elicit any response from oviductal tissues of either group. Unlike the uterus and the oviduct, the ovaries contracted slowly and irregularly. They responded with varying degrees of stimulation; ovaries from pregnant cows with brief and mild stimulation and ovaries from nonpregnant cows with slower and relatively stronger stimulation. Results indicate that the bovine ovary contracts rhythmically and that its sensitivity to PGF2 alpha decreases during pregnancy in contrast to the bovine uterus which becomes increasingly sensitive during pregnancy.  相似文献   

16.
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   

17.
Reasons for performing the study: During embryo transfer (ET) the equine embryo can tolerate a wide degree of negative asynchrony but positive asynchrony of >2 days usually results in embryonic death. There is still confusion over whether this is due to the inability of the embryo to induce luteostasis or to an inappropriate uterine environment. Objectives: To assess embryo survival and development in an advanced uterine environment. Hypothesis: Embryo–uterine asynchrony, not the embryo's inability to induce luteostasis, is responsible for embryonic death in recipient mares with a >2 days chronologically advanced uterus. Methods: Experiment 1: Thirteen Day 7 embryos were transferred to the uteri of recipient mares with luteal prolongation, occasioned by manual crushing of their own conceptus, such that donor–recipient asynchrony was between +13 and +49 days. Experiment 2: Day 7 embryos were transferred to recipient mares carrying their own conceptus at Days 18 (n = 2), 15 (n = 2), 14 (n = 4), 12 (n = 4) or 11 (n = 4) of gestation. In addition, Day 8 embryos were transferred to 4 pregnant recipient mares on Day 11 of gestation. Results: No pregnancies resulted following transfer of Day 7 embryos to recipients in prolonged dioestrus with asynchronies between +13 and +49 days. However, the use of early pregnant mares as recipients resulted in 5/20 (25%) twin pregnancies, 4 of which came from the transfer of a Day 8 embryo to a Day 11 recipient. All transferred embryos showed retarded growth, with death occurring in 4/5 (80%). Conclusions and potential relevance: The results emphasise the importance of an appropriate uterine environment for embryo growth and the inability of equine embryos to survive transfer to a uterus >2 days advanced even when luteostasis is achieved. It is possible that in normal, non‐ET equine pregnancy, embryo–uterine asynchrony may account for some cases of embryonic death.  相似文献   

18.
OBJECTIVES: To determine the prevalence of fetal resorption in 77 pregnant bitches and its association with the age, size and body condition score of the bitch and to determine the frequency of transuterine migration of embryos. METHODS: The number and position of embryos or fetuses and placental zones were registered postmortem. The prevalence of fetal losses was determined by comparing the number of corpora lutea with the number of embryos or fetuses in each bitch. The prevalence of transuterine migration of embryos was determined by correlating the number of fetuses in each horn and the number of corpora lutea in the ipsilateral ovary. RESULTS: Fetal resorption zones were demonstrated in 42.9 per cent of the bitches. However, pregnancy continued in 84.9 per cent of cases. Of the fetal losses, 25.9 per cent were determined by counting the number of corpora lutea and viable embryos or fetuses. Young bitches tended to have a higher probability of fetal resorption than adult bitches (P<0.06). The presence of fetal resorption zones was not associated with size or body condition. Transuterine migration of embryos had occurred in 15.8 per cent of the bitches. CLINICAL SIGNIFICANCE: This study demonstrated that embryo resorption is a normal event in the bitches, with a higher prevalence than previously thought.  相似文献   

19.
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   

20.
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   

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