239 Increased Preovulatory Estradiol Improves Pregnancy Success of Embryo Transfer in Beef Cows

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 124-125
Author(s):  
Jaclyn Ketchum ◽  
George A Perry ◽  
Kaitlin M Epperson ◽  
Lacey Quail ◽  
Makayla Ogg ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Repeated Measures ◽  
Fixed Effects ◽  
Beef Cows ◽  
Pregnancy Rates ◽  
Treatment Control ◽  
Time Interaction ◽  
Plasma Estradiol ◽  
Preliminary Study

Abstract Preovulatory estradiol concentrations and expression of estrus have been associated with greater pregnancy rates in beef cattle following AI, thus an experiment was designed to determine if supplemental estradiol (E2) at GnRH-induced ovulation would improve pregnancy retention in postpartum beef cows after embryo transfer. Cows were synchronized with the 7-d CO-Synch + CIDR® protocol. On d0 (48h post-prostaglandin) cows were grouped by estrual status (Estrual; n=198, nonestrual; n=406). Nonestrual cows were administered GnRH and randomly assigned to either no treatment (Control; n=204) or administration of 0.1 mg (IM) estradiol 17-β (Estradiol; n=202). In a preliminary study, 0.1 mg (IM) estradiol 17-β increased plasma estradiol (17.11±3.4 pg/mL; P < 0.01) and remained elevated above baseline for approximately 8h compared to control (1.70±0.58 pg/mL). All cows received an in vivo produced embryo on d7. Embryos were matched by grade, stage, and flush across treatments. Pregnancy was classified on d30 by either plasma pregnancy-associated glycoproteins analysis (Year 1) or ultrasonography (Year 2). Plasma estradiol concentrations (d-2, d0h0, d0h2) were analyzed by PROC MIXED as repeated measures in SAS(9.4), while GLIMMIX procedures were used to analyze differences in pregnancy rates with treatment, group, year, and their interactions as fixed effects. There was a treatment by time interaction (P < 0.001) in E2 concentration. There was no difference in plasma E2 concentrations on d0h0 (P >0.30) between treatments. At d0h2, Estradiol cows (15.7±0.25 pg/mL) had greater plasma E2 compared to Estrual (4.0±0.13 pg/mL) or Control (3.4±0.25 pg/mL) cows (P < 0.001), and Estrual cows had greater plasma E2 than Control cows (P = 0.02). Control cows had decreased (26%) pregnancy rates compared to both Estradiol (37%; P = 0.03) and Estrual (40%; P = 0.01) cows. Pregnancy rates did not differ (P = 0.51) between the Estrual and Estradiol cows. In conclusion, elevated preovulatory concentrations of estradiol are critical for improved pregnancy retention following embryo transfer.

Establishing twin pregnancies in cattle by embryo transfer

1995 ◽  
Vol 61 (1) ◽  
pp. 25-33 ◽  
Author(s):  
K. D. Sinclair ◽  
P. J. Broadbent ◽  
D. F. Dolman ◽  
R. G. Watt ◽  
J. S. Mullan
Keyword(s):  
Embryo Transfer ◽  
Twin Pregnancy ◽  
Beef Cows ◽  
Pregnancy Rates ◽  
Uterine Horn ◽  
Embryo Survival ◽  
Pregnancy Status ◽  
Twin Pregnancies

AbstractAn experiment zoas conducted to assess differing methods of twin pregnancy establishment in Hereford × British Friesian beef cows and heifers. The experiment was 2 × 2 × 2 × 2 factorial design in which the factors were (i) source of embryos (in vivo or in vitro produced); (ii) pregnancy status of recipient (inseminated or non-inseminated); (Hi) method of embryo transfer (surgical or cervical); and (iv) uterine location of a native and transferred embryo, or two transferred embryos (both located in the ipsilateral, or one in each of the ipsi and contralateral uterine horns). Pregnancy and twinning rates for 285 animals used for embryo transfer were initially diagnosed at day 56 after induced oestrus by transrectal ultrasonography. Subsequently, calving rate and birth weiglit at calving were recorded.Pregnancy rates at day 56 after induced oestrus were similar for both surgical and cervical transfers (58·6% v. 55·2%), as was the case for twinning rate (36·2% v. 30·0%). Similarly, there were no differences between these two methods of transfer (50·0% v. 46·9%) and (26·1% v. 17·7%) for calving and twin calving rates respectively. Recipients which had two embryos located in the ipsilateral uterine horn had higher (P < 0·001) pregnancy rates (66·6% v. 47·3%) but similar twinning rates (32·6% v. 33·4%) at day 56 after induced oestrus to recipients which had one embryo located in each horn. A greater (P < 0·05) percentage of recipients with two embryos originally located in the ipsilateral horn calved (56·0% v. 41·0%) but fewer (P > 0·05) produced twins (17·8% v. 25·7%) than was the case for recipients which originally had one embryo located in each horn. In vivo produced embryos resulted in higher (P < 0·001) pregnancy rates (74·4% v. 39·7%) and twinning rates (48·3% v. 18·0%) at day 56, and higher (P < 0·001) calving rates (64·5% v. 32·7%) and twin calving rates (36·3% v. 7·6%) than did in vitro produced embryos. Inseminated (Al + ET) recipients had slightly greater (P>0·05) pregnancy rates (61·6% v. 51·6%) and twinning rates (36·9% v. 28·7%) than non-pregnant recipients which received two embryos. A greater (P<0·05) percentage of inseminated recipients (Al + ET) calved (54·3% v. 42·0%) than was the case for non-pregnant recipients which received two embryos. The percentage producing twins at calving were similar for these two methods of twin pregnancy establishment.Embryo survival to day 56 after induced oestrus averaged 45·0% and was found to be non-independent of its co-twin. From day 56 to parturition foetal loss averaged 21·0% and foetal survival was found to be independent of the fate of its co-foetus. Twin foetuses located in the same uterine horn were lighter at birth than twin foetuses located in separate uterine horns (33·0 v. 35·2 kg; P < 0·05).

scholarly journals 166 EFFECT OF TREATMENT WITH hCG OR GnRH AT THE TIME OF EMBRYO TRANSFER ON PREGNANCY RATES IN COWS SYNCHRONIZED WITH PROGESTERONE VAGINAL DEVICES, ESTRADIOL BENZOATE, AND eCG

2005 ◽  
Vol 17 (2) ◽  
pp. 234 ◽  
Author(s):  
R. Tribulo ◽  
E. Balla ◽  
L. Cutaia ◽  
G.A. Bo ◽  
P.S. Baruselli ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Bos Taurus ◽  
Body Condition Score ◽  
Bos Indicus ◽  
Beef Cows ◽  
Estradiol Benzoate ◽  
Pregnancy Rates ◽  
Condition Score ◽  
Pregnancy Status ◽  
To Receive

Although several studies have investigated the relationship between circulating progesterone and pregnancy rates in cattle, the beneficial effect of treatments that increase progesterone concentrations, by insertion of a progesterone (P4) releasing device or induction of an accessory CL with hCG, GnRH, or LH treatment, has resulted in inconsistent effects on pregnancy rates in embryo recipients. An experiment was designed to evaluate the effect of hCG or GnRH treatment, given at the time of embryo transfer without estrus detection, on pregnancy rates in recipients treated with intrauterine P4-releasing devices, estradiol benzoate (EB), and eCG. The experiment was performed in two replicates; non-lactating Bos taurus × Bos indicus crossbred beef cows with a body condition score between 2.5 to 3.5 (1-to-5 scale) were used (replicate 1, n = 180; replicate 2, n = 140). All cows received 1 g of P4 via a P4-releasing device (DIB, Syntex, Argentina) and 2 mg EB i.m. (Syntex) on Day 0, and 400 IU of eCG i.m. (Novormon 5000, Syntex) plus 150 μg d(+)cloprostenol i.m. (Ciclase, Syntex) on Day 5. DIBs were removed on Day 8 and all cows received 1 mg EB i.m. on Day 9. Recipients were not observed for signs of estrus, and those >1 CL, or a single CL with an area >256 mm2, received 195 Grade 1 and 46 Grade 2 frozen/thawed “direct transfer” embryos on Day 17. At the time of embryo transfer, recipients were randomly allocated to 1 of 3 treatment groups to receive 1500 IU hCG (Ovusyn, Syntex), 50 μg Lecirelina (GnRH, Gonasyn, Syntex), or no treatment (control) at that time. Ovarian ultrasonography was performed on Day 0 to determine ovarian status (only cows with a CL or a follicle >10 mm and uterine tone were used), on Day 17 to measure CL area, and 40 days after embryo transfer to determine pregnancy status. Data were analyzed by logistic regression and the effects of replication, technician, treatment, and embryo quality were considered in the model. From the 320 recipients treated with a DIB plus EB and eCG, 241 (75.3%) were selected to receive an embryo. Nine (3.7%) and 1 (0.4%) of the selected recipients had 2 and 3 CL, respectively. Pregnancy rates did not differ between replicates (replicate 1: 80/140, 57.1%; and replicate 2: 57/101, 56.4%; P = 0.84), technicians (technician 1: 65/118, 55.1%; and technician 2: 72/123, 58.5%; P = 0.64), or treatments (hCG: 43/80, 53.8%; GnRH: 45/83, 54.2%; and control: 49/78, 62.8% P = 0.99). However, pregnancy rates were higher (P = 0.001) in recipients receiving Grade 1 embryos (121/195, 62.1%) than in those receiving Grade 2 embryos (16/46, 34.8%). GnRH or hCG treatment at the time of embryo transfer did not increase pregnancy rates in recipients synchronized with P4 releasing devices, EB, and eCG. Research was supported by Syntex S.A., Estancia El Mangrullo S.A., and Agencia Cordoba Ciencia S.E.

204 RELATIONSHIP BETWEEN RESPIRATORY ACTIVITY AND THE PREGNANCY RATE OF BISECTED BOVINE EMBRYOS IN VIVO

2007 ◽  
Vol 19 (1) ◽  
pp. 219 ◽  
Author(s):  
S. Moriyasu ◽  
H. Hirayama ◽  
K. Sawai ◽  
S. Kageyama ◽  
S. Aoyagi ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Pregnancy Rate ◽  
Embryo Transfer ◽  
Respiratory Activity ◽  
Pregnancy Rates ◽  
Bovine Embryos ◽  
Chi Square ◽  
Important Indicator ◽  
Consumption Rates

Oxygen consumption is an important indicator of the metabolic activity of living cells, which may provide valuable information for evaluating embryo quality. We have found that the bovine embryos with high oxygen consumption possess stronger potential for further development. However, the relationship between respiratory activity and the pregnancy rate of embryos is still unclear. In this study, we investigated the respiration rates of bisected bovine embryos and the pregnancy rates of demi-embryos after embryo transfer. Compact morula-stage embryos were bisected evenly by micro glass needle. One hundred bisected embryos were incubated for 24 h in embryo culture medium (IVD101; Research Institute for the Functional Peptides, Yamagata, Japan) at 39�C under 5% CO2, 5% O2, 90% N2. After the incubation, demi-embryos were classified into 2 groups: blastocoel-formed (BC) and blastocoel-not-formed (CM) embryos. Oxygen consumption rates of demi-embryos were measured by scanning electrochemical microscopy (SECM; Hokuto Denko Corporation, Tokyo, Japan). Within 3 h after the measurement, 80 demi-embryos were transferred into recipient cows (one demi-embryo/one recipient) at 7–8 days after estrus. Recipient cows were diagnosed for pregnancy by ultrasonography approximately 40 days after estrus. Statistical difference was analyzed by Tukey's post-hoc test and chi-square test. A total of 27 recipient cows became pregnant; the pregnancy rates for cows with CM and BC demi-embryos were 40.6% (13/32) and 29.2% (14/48), respectively. Mean oxygen consumption rates (� 10-14 mol s-1) in pregnant and non-pregnant cows were 0.47 and 0.39 for CM demi-embryos and 0.63 and 0.52 for BC demi-embryos, respectively. Retrospective analysis showed that the respiratory activity of demi-embryos in the pregnant group was higher than those in the non-pregnant group. In particular, the pregnancy rates for demi-embryos with respiratory activity higher than 0.35 in CM and 0.40 in BC groups were 52.0% (13/25) and 35.9% (14/39), respectively. On the other hand, cows with demi-embryos having an oxygen consumption rate under 0.35 in CM (n = 7) and 0.40 in BC (n = 9) groups did not become pregnant. These results demonstrated that bovine demi-embryos with higher respiratory activity showed a high pregnancy rate after embryo transfer. It is generally known that the pregnancy rate after the transfer of bisected embryos is lower than that of whole embryos. The measurement of oxygen consumption by SECM procedures is a useful tool to assess the quality of pre-implantation embryos and may contribute to the improvement of the success rate for bisected embryo transfer.

37 EFFECT OF EMBRYO STAGE ON PREGNANCY RATE FOLLOWING DIRECT TRANSFER OF BOVINE EMBRYOS FROZEN IN ETHYLENE GLYCOL

2012 ◽  
Vol 24 (1) ◽  
pp. 131 ◽  
Author(s):  
J. F. Hasler
Keyword(s):  
Ethylene Glycol ◽  
Pregnancy Rate ◽  
Embryo Transfer ◽  
The United States ◽  
Pregnancy Rates ◽  
Bovine Embryos ◽  
Embryo Freezing ◽  
Percentage Points ◽  
Embryo Stage

Annually, more than 400 000 in vivo-recovered bovine embryos are officially reported by members of the Canadian and American Embryo Transfer Associations. Between 65 and 70% of these embryos are cryopreserved and more than 95% are frozen in ethylene glycol (EG). Statistics on factors affecting embryo freezing are difficult to obtain because many cattle breeders/farmers no longer report pregnancy rates back to embryo transfer (ET) practitioners. Concerns are often expressed as to the optimal stage at which to freeze bovine in vivo-derived embryos. This is a retrospective analysis of results from 5 commercial ET programs (1 in the United States, 3 in Canada and 1 in the Netherlands) for which pregnancy data relative to embryo stage at freezing were made available. Embryos representing 4 stages of development, as defined by the IETS (4 = late morula, 5 = early blastocyst, 6 = mid blastocyst and 7 = expanded blastocyst) are included in the data. The number of embryos thawed and transferred ranged from 3954 to 24 827 for the 5 programs, with a total of 72 828. Embryos were frozen in either 1.5 M EG or 1.5 M EG + 0.1 M sucrose and exposure time to cryoprotectant before cooling ranged from 4 to 40 min. Pregnancy rates are shown in Table 1. Although the pregnancy rate for stage 6 embryos was only 2.6 and 3.2 percentage points lower than stages 4 and 5, respectively, these differences were highly significant and pregnancy rates for stage 6 embryos were lower than those for stages 4 and 5 in 4 of the 5 ET programs. The small decreased survival of stage 6 embryos is probably only moderately important in a commercial context. However, the pregnancy rate of stage 7 embryos was lower than all other stages for the combined dataset as well as in all 5 ET programs, with the difference between stages 5 and 7 ranging from 6.5 to 16.4 percentage points. Clearly, stage 7 embryos survive freezing at a significantly lower rate than stages 4, 5 and 6 and neither time of exposure to EG nor inclusion of sucrose in the freezing medium provided an obvious improvement. Although bovine ET practitioners routinely attempt to collect embryos on day 7 post-oestrus, recovery of stage 7 embryos cannot always be avoided. Further investigation into factors contributing to the decreased survival of stage 7 embryos is warranted. Table 1.Effect of embryo stage on pregnancy rate of bovine embryos frozen in EG

363 FACTORS INFLUENCING PREGNANCY RATES FOLLOWING TRANSFER OF BOVINE IN VIVO EMBRYOS BIOPSIED FOR SEX DETERMINATION

2007 ◽  
Vol 19 (1) ◽  
pp. 297
Author(s):  
S. Li ◽  
W. Yu ◽  
J. Fu ◽  
Y. Bai ◽  
F. Jin ◽  
...  
Keyword(s):  
Pregnancy Rate ◽  
Embryo Transfer ◽  
Pregnancy Rates ◽  
Chi Square ◽  
Embryo Survival ◽  
Chi Square Test ◽  
First Time ◽  
Fresh Embryos

Data collected from commercial embryo transfer programs in 63 farms in China during June 2002 to December 2005 was analyzed to examine the effects of various factors (biopsy, freezing, sample size, embryo development and quality, in vitro culture, and recipient quality) on pregnancy rates of in vivo-biopsied embryos. Embryos were flushed from superovulated dairy cattle and subjected to a biopsy for sexing determination using protocols and sexing kits supplied by AB Technology Ltd. Fresh embryos were implanted on the same day or frozen with AG freeze medium (AB Technology Ltd., Pullman, WA, USA) for later transfer. Recipients were synchronized with CIDA + PG protocols. Embryos were cultured in 6-well dishes containing 1.3 mL of holding medium (AB Technology Ltd.) in each well at room temperature (20–25�C) for examination of embryo survival in vitro. The chi-square test was used in statistic analysis. The implantation of fresh embryos after biopsy did not affect pregnancy rates (49.6%, 257/518) compared to that of non-biopsied fresh and frozen–thawed embryo groups (52.9%, 47/140 and 46.6%, 177/380, respectively). However, for biopsied embryos subjected to frozen and thawed procedures before implantation, particularly for those subjected to the removal of a larger biopsy, a reduced pregnancy rate was observed (41.8%, 297/710; P &lt; 0.01). Pregnancy rates among biopsied embryos at 3 different development stages (morula-early blastocyst, blastocyst, and expanded blastocyst) were not different. Similar results were found between embryo groups of grade 1 and 2. A significant decrease in pregnancy rate (0/10) was observed with embryos held in vitro for a longer period of time (&gt;5 h), suggesting detrimental effects of in vitro conditions on embryo survival. The highest pregnancy rate (68.0%) was observed in recipients synchronized for the first time before being implanted with biopsied embryos. Significant decreases in such rates were found in recipients synchronized for the second or third times or those with an abortion history at the first or second synchronization-implantation treatment (P &lt; 0.01). Better pregnancy rates (45.6%, 41/90; 46.1%, 76/165; and 45.5%, 5/11) were obtained for recipients implanted with biopsied embryos at Days 7.5, 8.0, and 8.5 post-heat detection, respectively, compared to 16% at Day 7 (3/18, P &lt; 0.05). It is concluded that mechanical treatment (cutting) does not reduce the survival of biopsied embryos; however, cryopreservation reduces their ability to survive in vivo. The analyses also suggest that holding embryos in vitro should not be longer than 5 h unless more favorable in vitro conditions can be provided. To achieve better results of implantation of biopsied embryos, embryo transfer should be performed during 7.5–8.5 days post-estrus, and the healthy recipients synchronized for the first time should be used.

PSI-7 Comparison of 6-day versus 7-day CIDR protocol with GnRH and PGFα to synchronize crossbred beef cows for fixed-timed ai with sexed semen at two different times

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 281-282
Author(s):  
Nicole N Noga ◽  
Jeremy G Powell ◽  
Brittni P Littlejohn ◽  
Whitney L Rook ◽  
Martin Mussard ◽  
...  
Keyword(s):  
Fixed Effects ◽  
Prostaglandin F2α ◽  
Fixed Time ◽  
Beef Cows ◽  
Pregnancy Rates ◽  
Chi Square ◽  
Treatment Groups ◽  
Conception Rates ◽  
Sexed Semen ◽  
Chi Square Analysis

Abstract Preliminary data indicate that shortening the progesterone exposure with CIDR can improve conception rates compared to the established 7-day CO-Synch protocols. The objective was to determine the effects of shortening progesterone exposure from 7 days to 6 days among crossbred beef cows and fixed-time artificial insemination (FTAI) with sex-sorted semen. A total of 147 fall calving (September-November) crossbred beef cows from one location were randomized to one of four treatments: 1 and 4) 7-d CO-Synch + CIDR protocol with administration of gonadotropin-releasing hormone (GnRH) and a CIDR insert on day 0, prostaglandin F2α (PGF) at CIDR removal on day 7, and FTAI occurring 66 h (Treatment 1) or 74 h (Treatment 4) later; 2 and 3) 6-d CO-Synch + CIDR protocol with administration of GnRH and CIDR insert on day 0, prostaglandin F2α (PGF) at CIDR removal on day 6, and FTAI occurring 72 h (Treatment 2) or 80 h (Treatment 3) later. Sex-sorted semen from Angus sires was used for AI. Pregnancy was determined by ultrasound 40 days after AI. Pregnancy rate was analyzed using the MIXED procedure of SAS with CIDR and AI service time as fixed effects. Chi-square analysis was used to assess the number of pregnant and open cows in each treatment using the FREQ procedure of SAS. There was no difference (P = 0.78) in pregnancy rates between 6-d CIDR (0.59 ± 0.05%) and 7 d CIDR (0.57 ± 0.05%) protocols. Cattle bred a shorter period after CIDR removal (0.64 ± 0.05%) had numerically (P = 0.11) greater pregnancy rates compared to those with a longer period after CIDR removal (0.51 ± 0.05%). There was no difference in the number of pregnant and open cows between treatment groups. These data suggest that using a 6-day or 7-day protocol, regardless of breeding time, results in similar conception rates.

scholarly journals 161 PREGNANCY RATES OBTAINED AFTER EMBRYO TRANSFER AT FIXED TIME OF IN VIVO-, IVF- AND CLONED-DERIVED EMBRYOS

2005 ◽  
Vol 17 (2) ◽  
pp. 231
Author(s):  
J. Lagioia ◽  
M. Panarace ◽  
M. Marfil ◽  
M. Basualdo ◽  
J. Gutierrez ◽  
...  
Keyword(s):  
Pregnancy Rate ◽  
Embryo Transfer ◽  
Fixed Time ◽  
Pregnancy Rates ◽  
Transfer Programs ◽  
Estrus Detection ◽  
Group 2 ◽  
Low Efficiency ◽  
Group 1

The most important factor in bovine embryo transfer programs is the low efficiency in the utilization of the recipients; this low efficiency is associated with low response to synchronization protocols and failures in estrus detection. It has been shown that cows transferred at fixed time with in vivo-derived embryos resulted in high rates of recipients selected for transfer and high overall pregnancy rates (recipients pregnant/recipients treated) (Tribulo et al. 2002 Theriogenology 57, 563). An experiment was designed to evaluate the pregnancy rate in recipients transferred with in vivo (fresh and frozen), IVF, and cloned-derived embryos without estrus detection. A total of 1555 non-lactating Bos Taurus crossbred beef cows was divided into two groups. Cows from group 1 (n = 421) were synchronized with a progesterone intravaginal releasing device (1 g P4; DIB, Syntex®, Buenos Aires, Argentina) plus 2 mg of estradiol benzoate (EB) i.m. (Syntex®) on Day 0. On Day 5, they received 400 IU of eCG (Novormon 5000, Syntex®) i.m. and 150 μg of D-Cloprostenol (PGF2α) (Bioprost-D, Biotay®, Buenos Aires, Argentina). The DIB devices were removed on Day 8 and on Day 9, 1 mg of EB was injected. Day 10 was arbitrarily considered as the day of estrus. Cows from group 2 (n = 1134) received 2 doses of PGF2α 14 days apart and were checked for heat during 5 days after the second PGF2α dose. Cows of both groups were examined 7 days after estrus by ultrasonography (Pie Medical Scanner 200®) and those with a corpus luteum >10 mm of diameter were transferred nonsurgically with in vivo (fresh and frozen), IVF, and cloned-derived embryos. In group 1, 360 cows were transferred, and in group 2, 726 cows were transferred (Table 1). Pregnancy was diagnosed 23 days later by ultrasonography (Pie Medical Scanner 200®). The pregnancy rates were compared statistically between groups 1 and 2 by analysis of variance (Infostat, LSD Fisher). There was no significant statistic difference (P > 0.05) between pregnancy rate in group 1 and 2 with in vivo (fresh), IVF, and cloned-derived embryos. However, pregnancy rate of frozen in vivo-derived embryos was lower in group 1 than in group 2 (P < 0.05). Results showed that treatment using DIB combined with EB, PGF2α, and eCG associated with embryo transfer without estrus detection (group 1) had no difference in pregnancy rate when compared with the treatment where synchronization with PGF2α and heat detection were used (group 2). Another important advantage is the use the group 1 treatment for increasing the flexibility and efficiency in the management of the recipients of in vivo, IVF, and cloned-derived embryo transfer programs. Table 1. Comparison of pregnancy rates between group 1 (embryo transfer at fixed time) and group 2 (embryo transfer 7 days after estrus detection)

190 EFFECT OF THE PROPERTIES OF CERVICAL MUCUS ON PREGNANCY RATES IN HOLSTEIN HEIFERS AND COWS AFTER EMBRYO TRANSFER

2006 ◽  
Vol 18 (2) ◽  
pp. 203
Author(s):  
T. Maekawa ◽  
S. Morita ◽  
O. Douchi ◽  
H. Koyama
Keyword(s):  
Embryo Transfer ◽  
Evaluation Method ◽  
Subjective Evaluation ◽  
Selection Criterion ◽  
Pregnancy Rates ◽  
Cervical Mucus ◽  
Chi Square ◽  
Significant Difference

Selection of animals as recipients of embryo transfer is an important procedure of embryo transfer on farms. Most animals are evaluated for their acceptability as recipients based on the quality of their corpus leteum (CL). However, since rectal palpation is a subjective evaluation method, a more objective method of assessing the suitability of the recipient is required. Cervical mucus may be able to be used to evaluate the condition of the uterus indirectly. The purpose of this study was to investigate the relationship between the properties of cervical mucus and pregnancy rates after embryo transfer in Holstein heifers and cows. Cervical mucus was collected using a swab off the ostium uteri externum and was stained with 5% Giemsa's solution for 20 min one day before embryo transfer. The stained cervical mucus were classified based on the type of staining pattern (Kitamura et al. 2003 Theriogenology 59, 307) into five groups: filiaceous (Type 1), taenia (Type 2), claustral (Type 3), nubecula (Type 4), or aqueous (Type 5). Proportions of the types of cervical mucus and pregnancy rates were analyzed by chi-square test. In Experiment 1, 113 heifers and 266 cows were examined for cervical mucus type. No significant difference was observed in the proportions of the types of cervical mucus between heifers and cows (heifers: 35.4%, 18.6%, 16.8%, 25.7%, and 3.5%; cows: 24.4%, 14.3%, 20.3%, 30.8%, and 10.2% for Types 1∼5, respectively). In Experiment 2, either a fresh or frozen-thawed embryo was implanted in vivo in 84 heifers and 163 cows 7 days after estrus. The heifers and cows were judged to have normal sized CLs (normal, 17 mm or more) and have no vaginal abnormalities such as cervical mucus contaminated with pus and urovagina as per vaginal examination. The proportions of acceptable Type 5 recipients was lower than that of Type 1 (P < 0.05). The pregnancy rates were 47.6% for heifers and 45.4% for cows (Table 1). The pregnancy rates of Types 1–3 (53.5%) were significantly higher than for Types 4 and 5 (29.9%) in the cows (P < 0.05). Although there was no statistically significant difference, the same tendency was observed in the heifers. Pregnancy was unsuccessful in Type 5 recipients, both heifers and cows. The total pregnancy rates of Types 1–3 were significantly higher than for Types 4 and 5 (53.5% vs. 29.9%, P < 0.001). These results suggest that cervical mucus type can serve as an objective selection criterion for embryo recipients. Further, embryo transfer should be avoided in Type 5 recipients. Table 1. Cervical mucus type and pregnancy rates (%) in dairy cattle

scholarly journals 182LAPAROSCOPIC EMBRYO TRANSFER IN KOREAN BLACK GOATS

2004 ◽  
Vol 16 (2) ◽  
pp. 213
Author(s):  
S.T. Shin ◽  
S.K. Jang ◽  
H.S. Yang ◽  
O.K. Lee ◽  
Y.H. Shim ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Efficient Method ◽  
Pregnancy Rates ◽  
Capra Hircus ◽  
Operating Table ◽  
Polyethylene Tube ◽  
Pronuclear Microinjection ◽  
Duration Of Surgery ◽  
Transgenic Embryos

In this study, laparoscopic embryo transfer (ET) was conducted to overcome the disadvantages of laparotomic ET including invasiveness, adhesions and duration of surgery in Korean black goats (Capra hircus aegagrus). Transferred transgenic embryos were produced by DNA pronuclear microinjection of in vivo derived zygotes. Recipient goats were synchronized in estrus by using an intravaginal progesterone device CIDR® for 13 days and injection of 400IU PMSG 48hrs before CIDR® removal. Embryos were transferred on day 4 after CIDR® removal. Recipient goats were starved for 48hrs and suspended head down in an operating table at an angle of 45° to the horizontal under general anesthesia. A Veress needle (Vomed, Tuttlingen, Germany) was inserted through the abdominal wall to make a pneumoperitoneum. After obtaining sufficient pneumoperitoneum, a 5-mm laparoscope and grasping forceps (MGB, Berlin, Germany) were inserted through the 5-mm trocar sleeves. After investigation of the ovaries, uterine horns and oviducts, embryos in a polyethylene tube (SP 65, Nastume, Tokyo, Japan) were transferred into the oviduct via the infundibulum in 76 recipients. To compare the pregnancy rates, laparotomic ET was also conducted in 21 recipients. In both groups, two microinjected embryos were transferred per recipient. Pregnancy of the recipient goats was examined by ultrasound on day 30 after embryo transfer. Pregnancy rates of laparoscopic ET were significantly higher than those of laparotomic ET (46.1% v. 28.6%; P&lt;0.05). Our results suggest that laparoscopic ET is a highly efficient method for the transfer of goat embryos.

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