219 COMPARISON OF ESTRUS - OVULATION SYNCHRONIZATION TREATMENTS USING HOLSTEIN HEIFERS AS EMBRYO TRANSFER RECIPIENTS

2007 ◽  
Vol 19 (1) ◽  
pp. 226
Author(s):  
H. Ushijima ◽  
N. Tatsuno ◽  
Y. Hara ◽  
T. Mori ◽  
H. Murata ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Final Diagnosis ◽  
Estradiol Benzoate ◽  
Visual Observation ◽  
Pregnancy Rates ◽  
Corpora Lutea ◽  
Estrus Synchronization ◽  
Gnrh Analog ◽  
Estrus Detection ◽  
Rectal Palpation

The Ovsynch system (Pursley et al. 1995 Theriogenology 44, 915–923) has been effectively employed as the synchronization method of recipients for embryo transfer (ET) (Nishisouzu et al. 2004 Reprod. Fertil. Dev. 16, 212–213). To establish the most effective Ovsynch system, we experimentally assessed 3 different protocols by comparing resultant estrus-synchronization rates of Holstein heifers and pregnancy rates of the recipients after ET. Holstein heifers averaging 14–15 months old and weighing over 330 kg were used in this study. They were randomly separated into the following 3 groups: (1) Select-synch (SS) group: an intramuscular (IM) injection of 50 �g GnRH analog was given to heifers at a random stage of the estrus cycle, followed 7 days later by 2 IM injections of 7.5 mg PG analog at an interval of 6 h; (2) Co-synch (CS) group: another IM injection of 50 �g GnRH was given to the SS group at 48 h after the first injection of PG; and (3) Heat-synch (HS) group: an IM injection of 0.75 mg estradiol benzoate was given to the SS group at 24 h after the first injection of PG. Estrus detection was evaluated twice daily by visual observation and use of a Heat Mount Detector. All heifers were additionally injected with 1500 IU hCG 5 days after estrus, to ensure favorable luteal function (Nishigai et al. 2001 J. Reprod. Dev. 47, 283–294). Rectal palpation was used to select acceptable recipients, i.e. those having functional corpora lutea (CL) e17 mm in diameter for 7 days after showing estrus (Nishisouzu et al. 2004 Reprod. Fertil. Dev. 16, 212–213). The size of CL e17 mm was determined by rectal palpation by skillful transferors. Fresh embryos collected from super-ovulated cattle 7 days after estrus were nonsurgically transferred only into acceptable recipients that had functional CL and were properly synchronized, 7–8 days after estrus. Final diagnosis of pregnancy was carried out 60 days after ET. Data were analyzed by the chi-square test. The HS group showed significantly higher (P < 0.01) rates of estrus synchronization (87/89: 98%) at 24–72 h after PG injection, estrus detection (98%), and acceptable suitability as recipients with a functional CL (92%) compared to those of the SS (185/210: 88%, 87%, and 73%, respectively) and CS (68/81: 84%, 74%, and 69%, respectively) groups. The pregnancy rates of heifers that received an embryo were not significantly different among HS, SS, and CS groups (45/82: 55%, 78/153: 51%, and 25/56: 45%, respectively). However, because the yield rate of acceptable recipients in the HS group was higher than in the other groups, the final pregnancy rates (no. pregnant/no. synchronization treatment) of the HS group (50%) was significantly higher than those of the SS and CS groups (37%; P < 0.05, and 31%; P < 0.01, respectively). Taken together, these findings demonstrate that the HS protocol is effective for estrus–ovulation synchronization of Holstein heifers, thus improving the productivity of ET by increasing the yield rates of heifers with a functional CL which leads to acceptable pregnancy results.

213 THE EFFECT OF eCG TREATMENT IN AN ESTRUS SYNCHRONIZATION PROTOCOL ON PREGNANCY RATES AFTER EMBRYO TRANSFER IN HOLSTEIN HEIFERS

2007 ◽  
Vol 19 (1) ◽  
pp. 223
Author(s):  
T. Okazaki ◽  
E. Sasaki ◽  
K. Hasegawa ◽  
T. Takani ◽  
S. Abe
Keyword(s):  
Embryo Transfer ◽  
Prostaglandin F2α ◽  
Estradiol Benzoate ◽  
Pregnancy Rates ◽  
Control Group ◽  
Corpora Lutea ◽  
Estrus Synchronization ◽  
Chi Square ◽  
Synchronization Protocol

Recent studies have shown that the presence of accessory or multiple corpora lutea (CL) and increased progesterone (P4) concentrations reduced early embryonic mortality in cattle. The objective of this study was to evaluate the effect of equine chorionic gonadotropin (eCG) treatment on the number of CL, the P4 concentrations, and pregnancy rates after embryo transfer (ET). Holstein heifers (n = 120) from 7 dairy farms received an intravaginal progesterone-releasing device (CIDR; InterAg, Hamilton, New Zealand) and 2 mg IM of estradiol benzoate (EB; Gynandol®; Sankyo, Tokyo, Japan) at random stages of the estrous cycle. After 7 to 9 days, CIDRs were removed and 15 mg of prostaglandin F2α (PG; Pronalgon®; Pfizer Japan, Nagoya, Japan) were administered, followed by 100 µg IM GnRH (Conceral®; Takeda Pharmaceutical Co., Ltd., Osaka, Japan) 2 days later (Day 0). The heifers were placed at random into 3 groups for eCG treatment. The eCG was not administered in a control group (n = 53); heifers in other 2 groups received 1000 IU eCG (Peamex®; Sankyo, Japan) IM at the time (0 h group, n = 37) or 48 h before (48 h group, n = 30) PG injection/CIDR removal. On Day 7, heifers were examined by ultrasonography (Aloka SSD500; Aloka, Tokyo, Japan) for number of CL; heifers with at least one functional CL received an in vivo-derived frozen–thawed embryo by direct transfer. At the same time, a blood sample was collected to determine P4 concentration. Pregnancy rates were determined on Days 30 and 60 by ultrasonography and rectal palpation, respectively. The data were analyzed by ANOVA and means were compared with Fisher's PLSD. Proportional data were analyzed by the chi-square test. P4 concentrations (mean ± SD) on Day 7 were 1.8 ± 1.0, 5.6 ± 3.3, and 2.2 ± 1.1 ng mL−1 for the control, 48 h, and 0 h groups, respectively (48 h vs. control and 0 h; P < 0.001). The number of CL on Day 7 were 1.1 ± 0.4, 2.5 ± 1.4, and 1.8 ± 0.9 for the control, 48 h, and 0 h groups, respectively (control vs. 48 h and 0 h, and 48 h vs. 0 h; P < 0.01). Pregnancy rates did not differ between 0 and 48 h groups but both were higher than in the control group (Table 1). Results suggest that the estrus synchronization protocol with administration of eCG at the time of CIDR removal or 48 h earlier significantly increased the number of CL and the P4 concentration, and improved pregnancy rates in Holstein heifers after ET. Table 1.Pregnancy rates of Holstein heifers synchronized with CIDR and PG and treated with eCG

scholarly journals 165 SYNCHRONIZATION TREATMENT WITH NEW AND REUSED CIDR-B DEVICES: ESTRUS AND PREGNANCY RATES IN AN EMBRYO TRANSFER PROGRAM

2005 ◽  
Vol 17 (2) ◽  
pp. 233
Author(s):  
C.W. Solorzano ◽  
J.H. Mendoza ◽  
A. Villa-Godoy ◽  
C.S. Galina ◽  
S. Romo
Keyword(s):  
Embryo Transfer ◽  
Estradiol Benzoate ◽  
Pregnancy Rates ◽  
Estrus Synchronization ◽  
Transfer Program ◽  
Embryo Transfer Program ◽  
Group 3 ◽  
Group 2 ◽  
Rectal Palpation ◽  
Group 1

An earlier study demonstrated that in CIDRs used in adult cows on two previous occasions, there was still a sufficient amount of progesterone (P4) remaining that allowed estrus synchronization in heifers (Solorzano et al. 2004 Reprod. Fert. Dev. 16, 214). However, the diverse conditions existing in that study made a statistical comparison impossible. The objective of this study was to study the effect of new and used CIDRs, combined with estradiol benzoate (EB) and prostaglandin F2-α (PGF) treatments, on estrus synchronization rates (ESR) and pregnancy rates (PR) in an embryo transfer program in Brangus cows in a tropical climate. We used the same set of CIDRs in the same location in cows of the same breed, age, and body condition during three consecutive weeks. Cows were randomly allocated to one of three treatment groups. In Group 1, all cows (n = 44) were treated with a new 1.9-g CIDR (CIDR-B, InterAg, Hamilton, New Zealand), combined with 2 mg EB on Day 0. In Group 2, all cows (n = 43) were treated with a reused (first reuse) 1.9-g CIDR and 2 mg EB on Day 0. In Group 3, all cows (n = 42) received a reused (second reuse) 1.9-g CIDR and 2 mg EB on Day 0. CIDR devices were removed on Day 7 and all cows received PGF (0.25 μg cloprostenol) at that time. Estrus was expected to occur 24 h later. Seven days after estrus all cows showing heat were examined by rectal palpation, and those with a CL 15 mm in diameter or larger were selected to receive a frozen/thawed embryo (in 1.5 M ethylene glycol) by nonsurgical direct transfer. PR were determined by rectal palpation 60 days after estrus. In Group 1, a total of 90.9% of the cows displayed signs of estrus (40/44), and 42% of those that received a frozen embryo were pregnant (16/38). In Group 2, a total of 88.4% of the treated cows showed signs of estrus (38/43), and 37% of those recipients became pregnant (13/35). In Group 3, 88% of treated cows showed signs of estrus (37/42), and 36% of cows receiving an embryo were pregnant (13/36). ESR and PR were compared by χ2 and Fisher's tests, and no differences were found among the three groups studied. This confirms that, in 1.9-g CIDRs used on two previous and consecutive occasions, there is still a sufficient amount of P4 remaining that allows successful estrus synchronization and pregnancy rates in a third use.

193 EVALUATION OF A NOVEL ELECTRONIC ESTRUS DETECTION DEVICE IN RECIPIENTS SYNCHRONIZED FOR EMBRYO TRANSFER

2006 ◽  
Vol 18 (2) ◽  
pp. 204
Author(s):  
T. VanEtten ◽  
F. Ireland ◽  
D. Vandever ◽  
D. Kesler ◽  
M. Wheeler
Keyword(s):  
Embryo Transfer ◽  
Electronic Device ◽  
Time Windows ◽  
Electronic Devices ◽  
Accurate Determination ◽  
Visual Observation ◽  
Pregnancy Rates ◽  
Optimal Time ◽  
Estrus Detection

The ability to detect estrus in cattle is an important aspect for both successful artificial insemination (AI) and successful embryo transfer (ET). The use of estrus detection devices has allowed producers to more precisely determine when to breed their cattle. There have been many types of devices including chin-ball marking harnesses, dye patches, and even electronic devices that monitor the animal's activity. With the growing popularity in timed AI and ET, these devices have again become of great interest. The latest tool for estrus detection is the multi-use TattleTale" Heat Detector (Microdyne Co., LLC., St. Joseph, MO, USA). The TattleTale" is an electronic device that is placed in a patch and affixed to the tail head. It is activated by a 3-s mount with subsequent mounts recorded per h through 12 h. Twelve hours after activation the device flashes indicating that the animal is ready for breeding. Such devices may allow breeders to determine exactly when estrus began as well as identify the peak estrus period, resulting in more accurate determination of optimal time for AI or ET. The objective of this study was to compare the accuracy of estrus detection devices when analyzing detection records and pregnancy rates. Cows from the Dixon Springs Agricultural Center (Simpson, IL, USA) were randomly separated into two groups based on estrus detection devices, one group receiving Kamar� patches (Kamor, Inc., Steamboat Springs, CO, USA) and the other receiving TattleTales. Both groups were synchronized using the OvSynch protocol (Syntex, Buenos Aires, Argentina). Cows were checked twice each day for four consecutive days, with a fifth day occurring a week later when the embryos were transferred. Estrus results were analyzed using a PROC UNIVARITE and GLM analyses with differences between treatment means determined by the LSD method of SAS (SAS Institute, Inc., Cary, NC, USA). The TattleTale detected a higher percentage (P < 0.05) of the cows in estrus (92 vs. 70%) than the Kamar� patch. Further, the TattleTale detected more asynchronous recipients (in estrus >48 h before expected) and synchronous recipients (in estrus <24 h than expected), although not significant with this sample size. In the present study, the TattleTale was more accurate in detecting estrus (i.e. fewer pregnancies were observed without estrus detected). Using the TattleTale information, a breeder would be able detect more animals in estrus and determine the most accurate time to breed or transfer embryos. Practically, the use of estrus detection devices in combination with timed AI and ET could allow for the exclusion of animals not in estrus in the optimal time windows for AI or ET, thus saving valuable semen and embryos that would be otherwise wasted on asynchronous females. The advantages of this device to producers include improved pregnancy rates based on timed breeding, lower herd management costs due to reduced quantities of wasted semen or embryos and fewer cows being resynchronized. This device also records any mounting activity missed by visual observation alone. This work was supported by USDA RRF W-1171.

Effect of recombinant bovine somatotropin on pregnancy rates of Nellore cows resynchronized with the use of new DIB and third use, and inseminated at fixed-time

2015 ◽  
Vol 4 (1) ◽  
pp. 356-362
Author(s):  
Josemara Silva Santos ◽  
Tania Cavalcante ◽  
Francisca Elda Ferreira Dias ◽  
Domenica Palomaris Mariano de Souza ◽  
Alencariano J.S. Falcão ◽  
...  
Keyword(s):  
Artificial Insemination ◽  
Linear Models ◽  
Plasma Concentrations ◽  
Fixed Time ◽  
Estradiol Benzoate ◽  
Pregnancy Rates ◽  
Recombinant Bovine Somatotropin ◽  
Equine Chorionic Gonadotropin ◽  
Rectal Palpation ◽  
Intravaginal Device

The objective of the experiment was to evaluate the effects of recombinant bovine somatropin (rbST), and the reuse of the progesterone (P4) releasing devices in resynchronization, on the pregnancy rates of Nellore cows submitted to fixed-time artificial insemination. A group of 123 multiparae Nellore cows, was submitted to a resynchronization protocol: on day 0 a Bovine Intravaginal Device (DIB® ) with 1,0g of P4 was implanted, associated with intramuscular administration of 2,0mg of estradiol benzoate (IM); on day 8 DIB was removed; and 1,0mg of estradiol cypionate, 0,15mg of prostaglandin F2? and 300 UI of equine chorionic gonadotropin were administered; on day 10, fixed-time artificial insemination was conducted (FTAI). The cows were randomized into G1 (n=12) – without rbST / with used Bovine Intravaginal Device, G2 (n=50) – without rbST / with new DIB, G3 (n=11) - with rbST / with used DIB and G4 (n=50) – with rbST/ with new DIB. rbST was introduced on the eighth day of the protocol. Sixty days after TAI, pregnancy diagnoses were conducted, via rectal palpation. Blood samples were taken on day 0, 8 and 10 of the protocol, in order to assess P4 plasma concentrations. Pregnancy rates were statistically evaluated through Generalized Linear Models Theory and their significance was tested with Analysis of Deviance. Pregnancy rates were 58%, 40%, 81% and 48% for G1, G2, G3 and G4, respectively, with significant statistical difference for G3. Plasma concentrations of P4 were not statistically different among groups, or collections. In view of the results obtained, we concluded that the administration of rbST in association with P4 DIB, used for the third time, improves pregnancy rates. Estrus resynchronization and re-insemination positively impacted pregnancy rates.

scholarly journals COMPARISON OF LONG-TERM PROGESTERONE-BASED PROTOCOL ON REPRODUCTIVE PERFORMANCE OF PREPUBERTAL AND PUBERTAL BEEF HEIFERS.

2014 ◽  
Vol 19 (1) ◽  
Author(s):  
Emanoel Faleiros Silveira ◽  
Luiz Ernandes Kozicki ◽  
Marcio Saporski Segui ◽  
Romildo Romualdo Weiss ◽  
Ivo Walter Santos ◽  
...  
Keyword(s):  
Ultrasound Examination ◽  
Prostaglandin F2α ◽  
Estradiol Benzoate ◽  
Pregnancy Rates ◽  
Estrus Synchronization ◽  
Device Removal ◽  
Timed Artificial Insemination ◽  
Red Angus ◽  
Natural Service

The aim of this study was to investigate estrus synchronization in prepubertal and pubertal heifers (crossbred ½ Nelore x Red Angus - commercial herd) submitted to a long-term progesterone-based protocol for timed artificial insemination (TAI), as well as overall pregnancy rates. Four hundred forty-seven heifers underwent ultrasound examination of the ovaries and were assigned to one of 3 groups: (1) prepubertal heifers (PPNS; n = 114) with ovarian follicles <8 mm in diameter and no corpus luteum (CL) that were submitted to natural service (NS) by bulls for 10 days; (2) prepubertal heifers (PPTAI; n = 124) with follicles <8 mm in diameter and no CL that underwent estrus synchronization with injection of 4.0 mg estradiol benzoate (EB) and insertion of a controlled-release intravaginal progesterone (P4) device containing 0.558 g P4 on d 0, followed by P4 device removal and injection of 150 mg prostaglandin F2α and 0.6 mg estradiol cypionate (ECP) on d 8, and TAI on d 10; and (3) pubertal heifers (PTAI; n = 209) with follicles >8 mm in diameter and/or a CL that underwent the same protocol as PPTAI heifers. Overall pregnancy rate was determined by transrectal ultrasonography on d 45 after NS or TAI. Data were analyzed using the FREQ procedure of SAS (SAS Inst. Inc., Cary, NC). Pregnancy rates were as follows: 20.1% in PPNS, 37.0% in PPTAI, and 48.5% in PTAI (P < 0.05). In conclusion, TAI after estrus synchronization with a hormonal protocol using EB and ECP in prepubertal and pubertal heifers resulted in higher pregnancy rates than prepubertal heifers exposed to natural service, and exposure of prepubertal heifers to a long-term progesterone-based protocol effectively synchronized estrus.

scholarly journals 184PREGNANCY RATES AFTER ESTRUS SYNCHRONIZATION TREATMENT WITH NEW AND REUSED CIDR-B DEVICES

2004 ◽  
Vol 16 (2) ◽  
pp. 214 ◽  
Author(s):  
C.W. Solorzano ◽  
J.H. Mendoza ◽  
J. Oden ◽  
S. Romo
Keyword(s):  
New Zealand ◽  
Ethylene Glycol ◽  
Prostaglandin F2α ◽  
Estradiol Benzoate ◽  
Direct Transfer ◽  
Estrus Synchronization ◽  
Experimental Conditions ◽  
Statistical Comparison ◽  
Rectal Palpation ◽  
To Receive

It is not well known whether used CIDR devices containing progesterone (P4) combined with estradiol benzoate (EB) and prostaglandin F2α (PGF) can provide acceptable estrus synchronization rates (ESR) and pregnancy rates (PR) in ET or AI programs. Three experiments were designed to study the effect of new and used CIDR-B, with different P4, EB and PGF treatments on ESR and PR in a reproductive program in beef cattle in a tropical climate. Experiment 1 was a control to evaluate ESR and PR in lactating recipient females. All cows (n=284) were treated with a new 1.9-g CIDR (CIDR-B, InterAg, New Zealand), combined with 2mg EB and 50mg P4 on Day 0. CIDR devices were removed on Day 8 and all cows received 0.25mg cloprostenol at that time. Estrus was expected to occur 24h later. Seven days after estrus, all cows showing heat were examined by rectal palpation and those with a CL 15mm in diameter or larger were selected to receive a frozen/thawed embryo (1.5M ethylene glycol=EG) by nonsurgical direct transfer (DT). PR were determined by rectal palpation 60d after estrus. Ninety percent of the cows displayed signs of estrus (256/284) and 40% of those that received a frozen embryo were pregnant (96/239). Experiment 2 was designed to evaluate ESR and PR in dry recipient cows treated with a used CIDR-B (first reuse). All cows (n=274) were treated with a reused 1.9-g CIDR combined with 2mg EB and 50mg P4 on Day 0. CIDR devices were removed on Day 8 and all cows received 0.25mg cloprostenol at that time. Estrus was expected to occur 24h later. Seven days after estrus, all cows that showed estrus were rectally evaluated and those with a CL 15mm in diameter or larger received a frozen/thawed embryo (1.5M EG) by DT. A total of 93% of the treated cows showed signs of estrus (254/274) and 51% of those that received an embryo were pregnant (110/217). Experiment 3 was designed to evaluate ESR and PR in virgin heifers, treated with a used CIDR (second reuse). All heifers (n=414) were treated with a reused 1.9-g CIDR combined with 1mg EB on Day 0. CIDR devices were removed on Day 8 and all heifers were expected to show estrus 24h later. Approximately 12h after estrus, all heifers that showed signs of estrus were inseminated, using frozen/thawed semen from a single bull. Of the treated females, 78% showed signs of estrus (323/414) and 69% of the inseminated were pregnant (223/323). These results suggest that in a CIDR that was used in two previous occasions, there is still a remaining amount of P4 that allows estrus synchronization in heifers. Furthermore, the reutilization of CIDR-B devices can contribute to reduce the costs related to ET or AI programs in cattle. However, the diverse existing conditions among the 3 experimental groups in this study make a statistical comparison impossible. Therefore, further studies are needed, under controlled experimental conditions, to confirm the results obtained.

206 EFFECTS OF A COMBINATION OF A PRID, PGF2α AND eCG, ON ESTRUS SYNCHRONIZATION AND PREGNANCY RATE FOLLOWING EMBRYO TRANSFER IN HOLSTEIN HEIFERS

2007 ◽  
Vol 19 (1) ◽  
pp. 220 ◽  
Author(s):  
Y. Aoyagi ◽  
A. Ideta ◽  
M. Matsui ◽  
K. Hayama ◽  
M. Urakawa ◽  
...  
Keyword(s):  
Pregnancy Rate ◽  
Embryo Transfer ◽  
Plasma Concentrations ◽  
Pregnancy Rates ◽  
Bovine Embryo ◽  
Estrus Synchronization ◽  
Chi Square ◽  
End Of Treatment ◽  
Chi Square Analysis ◽  
Day Of Embryo Transfer

Successful bovine embryo transfer requires synchronization of luteolysis, estrus and ovulation. The objective of the present study was to evaluate the effect of a combination of a PRID, PGF2� and eCG, on estrus synchronization and pregnancy rate in recipient heifers. A PRID� (ASKA Pharmaceutical Co., Ltd., Tokyo, Japan) was inserted into the vagina at random days of the estrous cycle for 7 (n = 35) or 9 (n = 43) days. Two days before removal of the PRID, the heifers were injected with PGF2� IM (2 mL Resipron�-C containing 0.25 mg mL-1 cloprostenol; ASKA). About half of the heifers in each group received 250 IU eCG IM (Serotropin�; ASKA) at the time of PRID removal. Blood was collected several times from the start of treatment for 7 (n = 9) or 9 (n = 9) days and on the day of embryo transfer by jugular venipuncture; plasma was immediately separated and stored at -20�C until assayed for plasma concentrations of estradiol-17α (E2) and progesterone (P4). The E2 and P4 determinations were performed by enzyme immunoassay after extraction by diethyl ether. Pregnancy was determined by ultrasonography on Day 30 (Day 0 = estrus). The rates of successful standing estrus (no. in estrus/PRID inserted), embryo transfer (no. transferred/estrus), and pregnancy (no. pregnancy/transferred) were compared between groups. Data were analyzed by chi-square analysis or Fisher&apos;s PLSD test following ANOVA. Injection of eCG at the time of PRID removal had no significant effect on the rates of successful standing estrus, embryo transfer, or pregnancy (P &gt; 0.05). The proportion of heifers treated for 9 days that exhibited standing estrus (93&percnt;, 40/43) was significantly higher than the proportion of heifers treated for 7 days that exhibited standing estrus (66&percnt;, 23/35, P &lt; 0.01). Of the heifers that were treated for 9 days, the proportion of heifers exhibiting standing estrus within 2 days after the end of treatment was significantly higher (93&percnt;, 37/40) than for heifers that were treated for 7 days (65&percnt;, 15/23; P &lt; 0.01). Pregnancy rates of heifers treated for 9 days (84&percnt;, 32/38) and 7 days (81&percnt;, 17/21) were not significantly different. The E2 : P4 ratio normally increases during follicle growth and CL regression. The plasma E2 : P4 ratio between the time of injection of PGF2&alpha; and the time of PRID removal was significantly higher for heifers that were treated for 9 days than it was for heifers that were treated for 7 days (P &lt; 0.01). These results suggest that a combination of PRID treatment for 9 days and injection of PGF2&alpha; 2 days before PRID removal successfully synchronized estrus in recipient heifers and led to high pregnancy rates following embryo transfer.

205 INCREASED PREGNANCY RATES OF POOR QUALITY BOVINE EMBRYOS BY ASSISTED HATCHING

2007 ◽  
Vol 19 (1) ◽  
pp. 219
Author(s):  
A. Taniyama ◽  
Y. Watanabe ◽  
Y. Nisino ◽  
T. Inoue
Keyword(s):  
Embryo Transfer ◽  
Zona Pellucida ◽  
Poor Quality ◽  
Pregnancy Rates ◽  
Assisted Hatching ◽  
Bovine Embryos ◽  
Production Rates ◽  
Chi Square ◽  
Chi Square Test ◽  
Rectal Palpation

Embryo transfer after superovulation is commonly used for efficient embryo and animal production and for genetic improvement in cattle. However, the quality of collected embryos varies greatly, which affects pregnancy rate. Usually, poor quality embryos are related to low pregnancy rates after embryo transfer and low viability after cryopreservation. Therefore, it is important to improve chances for survival of poor quality embryos after embryo transfer. The objective of this experiment was to improve pregnancy rates by applying the assisted hatching technique to poor quality embryos. Embryos were collected from Japanese Black cows after superovulation on Day 7 post-insemination. After being washed, embryos were morphologically classified. Embryos having more than 30% degenerated cells were assigned as poor quality embryos. The assisted hatching of embryos (cutting the zona pellucida) was performed under a stereoscope or an inverted microscope by making a cutting slit on the zona pellucida for about 20% of its circumference using a micromanipulator equipped with a cutting needle and holding pipette. After cutting, single or two embryos were transferred fresh to one uterine horn of recipient cows on Day 7 of the estrous cycle. Pregnancy and calf production rates were compared between 2 embryo transfer groups composed of fresh zona-cut embryos (ZC group) or fresh embryos with non-cut zonae pellucidae (NZC group). Pregnancy rates were determined by rectal palpation on Day 45, and calf production rates were calculated by the following formula: number of calves born/number of pregnancies. Statistical analysis was carried out using the chi-square test. Pregnancy rates of poor quality embryos in the double ET ZC group (60.3%; 44 pregnancies/73 transfers) were significantly higher (P &lt; 0.05) than those in the single ET NZC group (25.0%; 6 pregnancies/24 transfers) and in the single ET ZC group (44.0%; 37 pregnancies/84 transfers). Calf production rates were 67.3%, 45.5%, and 35.6% for the double ET ZC group, the double ET NZC group, and the single ET ZC group, respectively. Pregnancy rates of poor quality bovine embryos after double ET were remarkably improved by assisted hatching compared with those of single ET with non-assisted hatching. These results suggest that the combined methods of assisted hatching and double ET may be beneficial to produce calves from poor quality embryos.

289 EFFECTS OF YEAR PERIOD, TECHNICAL TEAM, AND BREED ON THE PREGNANCY RATES AFTER TRANSFER OF IVF BOVINE EMBRYOS IN THE SOUTHERN REGION OF RIO DE JANEIRO

2010 ◽  
Vol 22 (1) ◽  
pp. 301
Author(s):  
B. G. Moura ◽  
J. Almeida ◽  
F. L. Lima ◽  
G. Balbi ◽  
R. Calmerani ◽  
...  
Keyword(s):  
Beef Cattle ◽  
Dairy Cattle ◽  
Embryo Transfer ◽  
Pregnancy Rates ◽  
Chi Square ◽  
Chi Square Test ◽  
Few Data ◽  
Rectal Palpation ◽  
Fresh Embryos

The aim of the work was to study the effects of year period, technical team, breed, beef cattle and dairy cattle on the pregnancy rates in fresh embryos used in bovine transfer of IVF programs. The study was carried out at the fertilization laboratory In Vitro Nyltta Britto de Carvalho, in partnership with In Vitro Brazil, located at the Boa Vista farm, Barra do Pirai, during August 2007 to September 2008, seeking subsidies to improve the use of the technique in the field. During that period, aspirations and inovulations in 3 different periods I (August to December), II (January to April), and III (May to September) were carried out. The jobs were accomplished by 9 technical teams (A, B, C, D, E, F, G, H, and I) rendering services to the laboratory, by working with 2 beef breeds (Brahman and Nelore) and 3 dairy breeds (Gir, Girolando, and Holstein). The different breed receivers were synchronized, and in general, from 6 to 8 days after heat, they received embryo transfer, the cervical way, under low epidural anesthesia, where each female received 1 fresh embryo of IVF. All cows were submitted to gestation diagnosis by rectal palpation and ultrasonography, in general, 42 days after embryo transfer. The numbers of embryo transferred and pregnancy rates were submitted to the chi-square test, which presented significant differences (P < 0.05). There were pregnancy rates of 36.25%a (n = 960), 39.83%a (n = 1180), and 32.59%b (n = 919) in the I, II, and III periods, respectively. Among the 9 technical teams, there were verified pregnancy rates (%) of 33.51d (n = 1313), 30.30d (n = 330), 35.00cd (n = 405), 39.24cd (n = 1060), 59.25a (n = 7), 33.33d (n = 24), 53.57bc (n = 28), 43.31c (n = 157), and 58.33ab (n = 12) for A, B, C, D, E, F, G, H, and I teams, respectively. Among breeds there were rates (%) of 36.89ab (n = 412), 34.68b (n = 1286), 35.13ab (n = 74), 38.94a (n = 1140), and 37.80ab (n = 82) for Brahman, Nelore, Gir, Girolando, and Holstein, respectively. In the study, pregnancy rates (%) of 35.21b (n = 1698) in beef cattle and 38.65a (n = 1296) in dairy cattle were observed. The differences in pregnancy rates with respect to the evaluated factors, may be explained by individual, breed, and nutritional variations of the animals. There are few data in the literature with results on the embryo transfer use of IVF bovine under field conditions.

109 RELATIONSHIP BETWEEN ULTRASONIC MORPHOLOGY OF CORPUS LUTEUM IN HOLSTEIN HEIFERS AND PREGNANCY RATE AFTER EMBRYO TRANSFER

2012 ◽  
Vol 24 (1) ◽  
pp. 167
Author(s):  
A. Shirasawa ◽  
Y. Nakamura ◽  
A. Ideta ◽  
Y. Oono ◽  
M. Urakawa ◽  
...  
Keyword(s):  
Corpus Luteum ◽  
Pregnancy Rate ◽  
Embryo Transfer ◽  
Blood Clot ◽  
Pregnancy Rates ◽  
Bovine Embryo ◽  
Tissue Area ◽  
The Mean ◽  
Rectal Palpation ◽  
Experimental Group

Recipient animals for bovine embryo transfer (ET) are routinely selected according to the morphology of the corpus luteum (CL) estimated by rectal palpation. However, rectal palpation is not a precise method of diagnosing the functional status of a CL. Ovarian ultrasonography (US) may be used to improve such diagnoses. The aim of this study was to evaluate the relationship between ultrasonographic images of CL and pregnancy rates after ET in Holstein heifers to determine whether US can be used to select recipients for ET. Recipient heifers (n = 285) were selected by detection of natural oestrus or following oestrus synchronization using a progesterone-releasing intravaginal device (PRID; ASKA Pharmaceutical, Tokyo, Japan). Transrectal US was performed immediately before ET, on Days 6 to 8 of the oestrous cycle (oestrus = Day 0), using a B-mode scanner (HS1500V; Honda Electronics Co. LTD, Aichi, Japan) equipped with a 7.5-MHz linear-array transducer designed for intrarectal placement. A cross-sectional image of the maximal area of the CL and luteal cavity was obtained. The areas of the CL and luteal cavity were each calculated using the formula for the area of an ellipse (height/2 × width/2 × π). (1) Ultrasonic morphology of CL was classified into 3 types: without cavity (n = 128), with cavity (n = 145) and with blood clot (n = 12). (2) The luteal cavity was categorized into 3 groups: small (<100 mm2, n = 93), medium (100 ≤ x < 200 mm2, n = 32) and large (≥200 mm2, n = 20). (3) Luteinized tissue area (total area of CL minus the area of the luteal cavity) was categorized into 3 groups: small (<250 mm2, n = 61), medium (250 ≤ x < 350 mm2, n = 128) and large (≥350 mm2, n = 84). In vivo–produced embryos were transferred nonsurgically into the uterine horn ipsilateral to the CL. Pregnancy was determined by transrectal US on Days 30 to 40 of gestation. The pregnancy rates of each experimental group were analysed by logistic regression. In this study, the pregnancy rate did not differ significantly in each experimental group: (1) without cavity: 77.3% (99/128), with cavity: 75.2% (109/145) and blood clot: 75.0% (9/12); (2) small cavity: 73.1% (68/93), medium: 75.0% (24/32) and large: 85.0% (17/20). The mean area of the cavity was 100.8 ± 110.3 mm2 (mean ± standard deviation) and recipients with 0 to 539.7 mm2 sized cavities had successful pregnancies (observational range was 0 to 539.7 mm2). (3) The pregnancy rates of recipients that had small, medium and large luteinized tissue were 77.0% (47/61), 75.0% (96/128) and 77.4% (65/84), respectively. The mean area of luteinized tissue was 318.9 ± 90.3 mm2 and 155.0 to 620.0 mm2 sized luteinized tissue had pregnancy success (observational range was 132.8 to 620.0 mm2). In conclusion, the results from this study indicate that the presence of a luteal cavity or blood clot has no detrimental effect on pregnancy success after ET in Holstein heifers. Furthermore, no relationship was found between luteinized tissue area at the time of ET and pregnancy rate.

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