170 PREGNANCY RATES OF NONCYCLING RECIPIENT MARES TREATED WITH A NEW FORMULATION OF LONG-ACTING PROGESTERONE

2010 ◽  
Vol 22 (1) ◽  
pp. 243
Author(s):  
M. M. B. Castro Chaves ◽  
C. G. Schutzer ◽  
M. A. Alvarenga
Keyword(s):  
Embryo Transfer ◽  
Estradiol Benzoate ◽  
Pregnancy Rates ◽  
Control Group ◽  
Limiting Factor ◽  
Transfer Programs ◽  
Embryonic Loss ◽  
Exogenous Progesterone ◽  
Long Acting ◽  
New Formulation

The mare being a seasonal polyestrous animal is a limiting factor for maintenance of embryo transfer programs during the entire year.At the beginning and end of the breeding season, the percentage of recipients showing normal estrous cycles may be low compared to donors. Exogenous progesterone has been administered to acyclic mares to allow them to be used as recipients. Noncyclic recipient mares treated once a week with long-acting progesterone (P4) have been widely used in Brazil in equine embryo transfer (ET) programs. P4LA was developed for weekly administration of 1.5 g of P4 to acyclic recipients until approximately 120 days of pregnancy. The aim of the present experiment was to evaluate the pregnancy rates of noncyclic recipients treated with a new formulation of long-acting P4 developed in our laboratory that allows a longer interval between treatments (14 days). Noncyclic mares (n = 36) were used as recipients between August and September of 2008 (transition between winter and spring in Brazil). Noncyclic mares were treated with 5 mg of estradiol benzoate during 2 consecutive days followed by the application of 10 mL (i.m.) of P4LA containing 300 mg mL-1 of P4, for a total P4 dose of 3 g. Embryos were transferred between 6 to 12 days after P4LA injection. The same dose of P4LA was repeated on the day of ET and every 14 days until 110 days after pregnancy diagnosis. One hundred fifty-five cyclic recipients were used as a control group, with embryos transferred 4 to 8 days after ovulation. No differences were observed (P > 0.05) when comparing pregnancy rates from acyclic recipients treated with P4LA (82%, 56/68) or cyclic recipients (88%; 137/155) on Day 15. The rate of embryonic loss at 50 days was similar (P > 0.05) for noncycling (11%) and cycling recipient mares (10%). The results obtained in the present study demonstrated that the new formulation of P4LA containing 300 mg mL-1 of P4 and administered every 14 days was effective in maintaining pregnancy in noncyclic recipient mares, allowing a larger treatment interval and longer window of time to transfer embryos.

151 PREGNANCY RATES AFTER A NONSTEROIDAL ANTI-INFLAMMATORY (FLUNIXIN MEGLUMINE) AND PROGESTERONE (P4) ADMINISTRATION TO MANGALARGA MARCHADOR RECIPIENT MARES

2011 ◽  
Vol 23 (1) ◽  
pp. 179
Author(s):  
P. G. Rodrigues ◽  
A. M. Resende ◽  
J. C. Souza ◽  
R. R. Carvalho ◽  
R. Maculan
Keyword(s):  
Embryo Transfer ◽  
Pregnancy Rates ◽  
Transfer Programs ◽  
Orthogonal Contrasts ◽  
Flunixin Meglumine ◽  
Proper Diagnosis ◽  
Inflammatory Drugs ◽  
Anti Inflammatory ◽  
Long Acting ◽  
Day Of Embryo Transfer

The aim was to evaluate whether pregnancy rates could be improved by randomly injecting recipient mares with flunixin meglumine (FM; Banamine®, Schering-Plough, São Paulo, Brazil) on the day of embryo transfer combined or not with long-acting progesterone (P4) in commercial embryo transfer programs. One hundred sixty-five Mangalarga Marchador recipient mares from the 2006–2007 breeding season of 4 different commercial programs were used. Ages ranged from 4 to 15 years old. In 86 mares, 1.1 mg kg–1 of BW of FM was given intravenously immediately after embryo transfer, and in 79 mares, only saline was injected. Additionally, 59 mares receiving saline were injected with 1 800.0 mg of progesterone at embryo transfer and every week thereafter until 110 days of gestation. Of the 86 receiving FM, 17 received the same progesterone protocol. Embryos were transferred nonsurgically in Ham’s F-10 or Encare medium. Pregnancy was checked by ultrasonography at 15, 30, and 60 days after transfer, and only a positive diagnosis on the latter was considered pregnancy in the statistical analysis. In a 2 × 2 factorial design (2 levels of FM and P4), pregnancy rates were analysed using the GENMOD procedure considering a binomial distribution (SAS®, Cary NC), and means were compared by orthogonal contrasts. Pregnancy rates were lower (P < 0.0001) in FM-treated (50.2 ± 5.3%) compared with control (88.2 ± 5.1%) mares and in P4-treated (85.9 ± 5.0%) compared with control (52.4 ± 5.5%) mares. An interaction effect between FM and P4 was not observed (P < 0.49). For mares receiving or not receiving FM, the addition of the P4 protocol lowered pregnancy rates. In mares not treated with FM, pregnancy rates were 81.4 ± 5.1% and 95.0 ± 8.8% for P4-treated and nontreated mares, respectively (P < 0.05). In FM-treated mares that did not receive P4, pregnancy rates were 76.8 ± 4.8% compared with 23.5 ± 9.6% of those treated with P4 (P < 0.0001). In conclusion, the indiscriminate use of progesterone and nonsteroidal anti-inflammatory drugs may actually decrease reproductive efficiency and even act synergistically to potentiate their effect. These results must be interpreted with caution, considering that the data are derived from field observations, although sources are from very reliable and well-controlled operations. Nevertheless, the authors consider it imperative to have a proper diagnosis before generalizing the use of medical tools to improve pregnancy rates in horses. Financial support from CNPQ–Conselho Nacional de Desenvolvimento Científico e Tecnológico, CAPES–Coordenação de Aperfeiçoamento de Pessoal de nível Superior. Schering/Plough, JOFADEL, and ABCCMM–Associação Brasileira dos Criadores do Cavalo Mangalarga Marchador.

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 &lt; 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 &lt; 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

136 EARLY EMBRYONIC LOSSES USING PROGESTERONE SUPPLEMENTATION IN CYCLIC AND NONCYCLIC RECIPIENT MARES

2010 ◽  
Vol 22 (1) ◽  
pp. 227
Author(s):  
G. H. M. Araujo ◽  
C. F. Moya-Araujo ◽  
A. N. Rocha ◽  
C. M. Burns ◽  
S. D. Burns ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Control Group ◽  
Chi Square ◽  
Chi Square Test ◽  
Embryonic Loss ◽  
Progesterone Supplementation ◽  
Embryo Loss ◽  
Exogenous Progesterone ◽  
Long Action ◽  
Embryonic Death

The aim of the present study was to determine the effectiveness of the commercial progesterone to maintain the pregnancies in noncyclic recipient mares and if it helps to decrease the early embryonic death when used in cyclic pregnant recipient mares. A total of 199 mares were used during February to April of the 2008 breeding season at Burns Ranch. The mares were assigned to groups according to their reproductive status. Noncyclic (n = 42) mares were prepared as embryo transfer recipients using our standard protocol with estradiol cypionate (3 days, 10/6/4 mg, Wickliffe, USA) and long action progesterone (P4LA, 1500 mg, BET Labs, Lexington, KY, USA), and 157 naturally cyclic mares were used from Day 3 to 8 after ovulation as embryo transfer recipients. After embryo transfer, 134 of the 157 cyclic mares got pregnant at 15 days. Some of the pregnant mares (n = 43) were assigned to a progesterone-supplemented group; these mares were administered P4LA (1500 mg) after the first pregnancy diagnosis at around 15 days and repeated 7 days later. The remaining mares were placed in a control group (n = 91), with no treatment, in order to compare the embryonic loss rates for the 3 groups. Recipients were evaluated for the presence of the embryonic vesicle between 13 and 16 days (embryo age), and pregnancies were monitored at 30 and 45 days to determine the early embryonic loss. Statistical analyzes were performed using the chi-square test with 5% defined as significance. Pregnancy rates at 13 to 16 days were not different (P = 0.336) for noncyclic and cyclic recipients (39/42, 90.7% and 134/157, 85.4%, respectively). The embryonic loss was evaluated in the 3 groups as follows: control group; 7 of 91 pregnancies were lost between 15 and 30 days (7.69%) and 2 of 84 were lost between 30 and 45 days (2.38%); the progesterone-supplemented group had lost 4 of the 43 pregnancies between 15 and 30 days (9.30%); and the noncycling progesterone mares had lost 2 of the 39 between 30 and 45 days (5.13%). Rates of embryo loss before 45 days of gestation were not different for the control mares with no progesterone supplementation (9.89%), progesterone-supplemented cyclic mares (9.3%), and noncyclic recipients (5.13%). The noncyclic recipients maintain gestation with the supplemental progesterone with no influence on embryo loss. These results demonstrate no advantage in the use of exogenous progesterone to supplementation for cyclic embryo recipients. Burns Ranch Inc., Menifee, California, USA.

176 PREGNANCY AND PREGNANCY LOSS RATES OF ACYCLIC RECIPIENT MARES TREATED WITH TWO DIFFERENT LONG-ACTING PROGESTERONE CONCENTRATIONS

2010 ◽  
Vol 22 (1) ◽  
pp. 246 ◽  
Author(s):  
G. M. Greco ◽  
J. A. Dell'aqua Jr ◽  
M. A. Alvarenga
Keyword(s):  
Embryo Transfer ◽  
Pregnancy Loss ◽  
Estradiol Benzoate ◽  
Pregnancy Rates ◽  
Chi Square ◽  
Chi Square Test ◽  
Group 2 ◽  
Long Acting ◽  
Group 1 ◽  
Loss Rates

Long-acting progesterone compounds containing concentrations of 150 mg mL-1 (P4LA150) have been routinely used in Brazil, especially at the beginning and end of the breeding season when the percentage of recipient mares showing normal estrous cycles is low compared to donors (Greco GM et al. 2008 Proceedings 7th International Symposium on Equine Embryo Transfer, 59-60). However, recipients treated with P4LA150 must receive weekly administrations until pregnancies achieve 100 days. The present study aimed to evaluate pregnancy and pregnancy loss rates from acyclic mares treated at 7-day intervals with P4LA150 and 14-day intervals with a long-acting progesterone formulation containing 300 mg mL-1 (P4LA300). Acyclic Campolina breed mares (n = 80) ranging from 4 to 13 years old showing considerable endometrial edema 2 days after estradiol benzoate injection (5 mg, i.m.) were split in 2 groups. Group 1 mares (n = 40) received 10 mL of P4LA150 (1500 mg) i.m. every 7 days, whereas Group 2 mares (n = 40) were treated with 10 mL of P4LA300 (3000 mg) i.m. every 14 days. Steroid hormone formulations were produced in our research laboratory, at São Paulo State University, Botucatu, Brazil. Embryos 7 to 8 days of age were transferred into the uteri of recipients between 4 and 7 days after the first progesterone administration. Following a positive pregnancy diagnosis at 14 to 15 days, mares were examined at Days 50 and 100, when progesterone treatment was discontinued. These evaluations were conducted in order to determine pregnancy loss rates during both periods. Results were analyzed through the chi-square test and significance was set at P < 0.05. Pregnancy rates and pregnancy loss rates at Day 50 from mares treated with P4LA150 (Group 1) and P4LA300 (Group 2) did not differ. Pregnancy rates were 60.0% (24/40) and 75.0% (30/40) at Day 50 for mares treated with P4LA150 (Group 1) and P4LA300 (Group 2), respectively (P > 0.10). Pregnancy loss rates at Day 50 were 8.3% (2/24) and 10.0% (3/30) for mares treated with P4LA150 and P4LA300, respectively (P > 0.10). Pregnancy losses were not identified at Day 100. Based on the results from the present study, we concluded that acyclic recipient mares treated with P4LA150 or P4LA300 are able to obtain satisfactory pregnancy rates with low pregnancy losses. Moreover, the use of 3000 mg of long-acting progesterone every 14 days reduces overall progesterone administrations, minimizes stress in horse handling, and makes the choice for acyclic recipient mares more appealing in commercial embryo transfer programs. Authors would like to thank FAPESP for financial support.

scholarly journals 380 Effects of estradiol benzoate on reproductive characteristics in beef cows

2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 145-145
Author(s):  
Lacey M Dysart ◽  
Caleb O Lemley ◽  
Riley Messman ◽  
Jamie E Larson
Keyword(s):  
Doppler Ultrasonography ◽  
Blood Perfusion ◽  
Beef Cows ◽  
Estradiol Benzoate ◽  
Pregnancy Rates ◽  
The Other ◽  
Control Group ◽  
Blood Samples ◽  
Doppler Probe ◽  
Imagej Software

Abstract Ovulation prompted by exogenous GnRH may cause the release of sub-mature oocytes and lead to decreased pregnancy rates. Inclusion of estradiol benzoate (EB) has improved pregnancy rates. The objective was to determine if EB affects blood perfusion of follicles, CL, or uterus, concentrations of estradiol, or incidence of standing estrus. Forty-seven suckled beef cows were synchronized (GnRH+CIDR on d -9, PGF2a+CIDR removal on d -2, expected estrus=d 0). On d -1, 24 of 47 cows received an injection of EB (1mg/2mL) while the other 23 remained as a control group. Ovaries were evaluated via Doppler ultrasonography on d -1, 0, 6, 14, and 21. A laser Doppler probe was used to measure blood perfusion of the uterus on d -1, 0, and 6. Only cows that exhibited estrus (n = 29) were evaluated on d 14 and 21. Images were analyzed via ImageJ software to determine mean area of perfusion. Blood samples were collected on d -1 and 0 and analyzed for concentrations of estradiol using RIA. Using SAS, MIXED and FREQ were used to determine the influence of treatment on blood perfusion and estradiol, and incidence of standing estrus, respectively. Treatment with EB increased (P &lt; 0.001) the number of cows exhibiting standing estrus compared to control (21/24 vs 8/23, respectively). Treatment of EB did not (P &gt; 0.10) alter blood perfusion of the follicles or uterus on any day or perfusion of the CL on d 6. However, EB increased (P &lt; 0.036) the size of the CL on d 14 (25.06±1.7 vs 6.06±3.7) and tended (P &lt; 0.097) to increase the size of the CL on d 21. Treatment of EB increased (P &lt; 0.003) concentrations of estradiol on d 0 compared to control (21.35±4.49 vs 9.44±4.61 pg/mL). In conclusion, treatment with EB may play a role in changing the CL after ovulation.

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.

Embryo Transfer in Anovulatory Recipient Mares Treated with Estradiol Benzoate and Long-Acting Progesterone

2013 ◽  
Vol 33 (3) ◽  
pp. 205-209 ◽  
Author(s):  
Fernanda Kaercher ◽  
Luiz Ernandes Kozicki ◽  
Carlos Eduardo Camargo ◽  
Romildo Romualdo Weiss ◽  
Ivo Walter dos Santos ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Estradiol Benzoate ◽  
Long Acting

scholarly journals 181COMPARISON OF THE PREGNANCY RATES AFTER SYNCHRONIZATION OF OVULATION USING GnRH AND PGF2± IN RECIPIENT DAIRY CATTLE

2004 ◽  
Vol 16 (2) ◽  
pp. 212 ◽  
Author(s):  
T. Nishisouzu ◽  
M. Sugawara ◽  
S. Aoki ◽  
K. Kishida ◽  
M. Moriyoshi ◽  
...  
Keyword(s):  
Dairy Cattle ◽  
Pregnancy Rate ◽  
Embryo Transfer ◽  
Fixed Time ◽  
Pregnancy Rates ◽  
Control Group ◽  
Corpora Lutea ◽  
Transfer Program ◽  
Chi Square ◽  
Follicle Diameter

Treatments with GnRH and PGF2α for synchronization of ovulation has resulted in acceptable pregnancy rates after fixed-time artificial insemination in dairy cows without estrus detection. The objective of the present study was to evaluate the practicability of ovulation synchronization (Ovsynch, Pursley JR et al. 1995 Theriogenology 44, 915–923) in dairy cattle using GnRH and PGF2α for the embryo transfer recipients. Dairy cattle (cows; n=100, heifers; n=88) were randomly allocated to one of two groups. The control group (cows; n=45, heifers; n=37) was composed of cows in natural estrus. The ovulation synchronization group (cows; n=55, heifers; n=51) was treated with an intramuscular injection of 100μg of GnRH at a random stage of the estrous cycle. Seven days later, the cattle received PGF2α (Cows; 25–30mg) or PGF2α analog (Heifers; 0.5mg) in order to regress the corpora lutea (CL). Forty-eight hours later, cows and heifers received a second injection of 100μg GnRH. Embryo transfer was carried out 7 days after the second injection of GnRH in the ovsynch group and 7 days after estrus in the control group. The cattle judged to have CL 17mm were classified as acceptable recipients. The size of the follicles and the CL were determined to be of estrus stage and embryo transfer by means of ultrasonography. The mean numbers of follicles and CL were analyzed by ANOVA, while pregnancy rates were analyzed by chi-square test. The results are presented in the Table. The proportion of cows and heifers determined to be acceptable embryo transfers was not different between the control group and the ovsynch group. There were no differences in the proportion of acceptable embryo transfers between the control group and the ovsynch group. Follicle diameter at the time of estrus in the control group (cows; 20.7±0.7mm, heifers; 16.8±0.5mm) were significantly larger than that of the ovsynch group (cows; 18.0±1.0mm, heifers; 14.7±0.2mm) (P&lt;0.05). Although CL diameter at the time of embryo transfer in heifers showed no differences between the control group and the ovsynch group (25.0±1.0mm v. 22.8±1.5mm), The CL diameter of the control cow group was larger than that of the ovsynch group (29.8±0.7mm v. 26.1±1.0mm, P&lt;0.05). However, no differences in pregnancy rate were seen between the control group and the ovsynch group. These results suggest that ovsynch can be effectively applied in an embryo transfer program for cattle. Table 1 Proportion of acceptable embryo transfer recipients and pregnancy rate in dairy cattle in the control ovsynch groups

13 USE OF A NEW INTRAVAGINAL DEVICE TO RELEASE PROGESTERONE IN FIXED-TIMED ARTIFICIAL INSEMINATION IN NELLORE COWS (BOS TAURUS INDICUS)

2010 ◽  
Vol 22 (1) ◽  
pp. 164
Author(s):  
F. A. Braga ◽  
F. J. D. Pardo ◽  
P. H. Miguez ◽  
A. Kehrle ◽  
J. R. V. Pimentel ◽  
...  
Keyword(s):  
Pregnancy Rate ◽  
Artificial Insemination ◽  
Body Condition Score ◽  
Estradiol Benzoate ◽  
Sao Paulo ◽  
Pregnancy Rates ◽  
Control Group ◽  
São Paulo ◽  
Effect Of Treatment ◽  
Intravaginal Device

Artificial insemination results can be improved using fixed-timed AI (FTAI). Currently, progesterone release devices, indispensable in FTAI procedures, such as DIB® (Schering-Plough, Kenilworth, NJ, USA), are made of silicone, a nonbiodegradable biocompatible polymer. Recently, biodegradable progesterone (P4)-releasing devices made of poly(3-hydroxy)butyrate-valerate copolymer (PHB-V) and poly-ϵ-caprolactona (PCL) have been developed. To investigate the efficiency on pregnancy rate of FTAI programs using a new intravaginal device made of PHB-V (Progestar®, Innovare, São Paulo, Brazil), 240 Nellore (Bos indicus) cows, between 3 and 8 years of age, were randomly assigned to 2 experiments. In experiment 1, new P4 devices DIB (control group, DIB1; n = 60) were compared with PHB-V (Progestar1; n = 76); in experiment 2, previously used DIB (DIB2; n = 52) and PHB-V (Progestar2; n = 52) devices were compared. All groups were treated with 2 mg of estradiol benzoate i.m. (Innovare) and received the intravaginal device according to group (Day 0). Together with P4 device withdrawal (Day 8) all animals received 300IU of eCG i.m. (Novormon®, Schering-Plough) and 150 μg i.m. of D-cloprostenol (Croniben®, Biogenesis-Bagó, Buenos Aires, Argentina). On Day 9, all cows were treated with 1 mg of estradiol benzoate and the FTAI was performed 30 h later. The data were submitted to ANOVA (PROC GLM of SAS, SAS Institute, Cary, NC, USA), separating as causes of variance the effect of treatment, postpartum period (PPP1-45 until 70 days and PPP2-71 until 90 days), body condition score (BCS4, BCS5, and BCS6 using a 1 to 9 scale), cyclicity (cycling and noncycling) and clean-up bulls (5 bulls nominated with numbers 1 to 5). Significant differences were considered to have P < 0.05. In experiment 1, interactions were not significant, there was no effect of treatment on FTAI (DIB1: 66.7% v. Progestar1: 65.8%) or breeding season pregnancy rates (BSPR; DIB1: 95.0% v. Progestar1: 94.7%) and no effect of other variables on FTAI pregnancy rates (FTAIPR) and BSPR. In experiment 2 there was no effect of treatment on FTAIPR (DIB2: 61.6% v. Progestar2: 55.8%) and BSPR (DIB2: 94.2% v. Progestar2: 88.5%). As ANOVA indicated a significant effect of clean-up bulls on BSPR, Tukey test was used to split it up. A bull of the Progestar2 group had lower performance (41.7%) causing the difference (albeit nonsignificant) on BSPR. This experiment showed that Progestar and DIB had the same efficiency on pregnancy rate and both treatments have the potential to produce FTAIPR >50% and BSPR >90%. Fapesp-Fundação de Amparo à Pesquisa do Estado de São Paulo. CNPq-Conselho Nacional de Desenvolvimento Científico e Tecnológico.

Use of a norgestomet implant to reduce embryonic loss and resynchronise oestrus in dairy heifers

1992 ◽  
Vol 1992 ◽  
pp. 119-119
Author(s):  
D N Logue ◽  
J A Bax ◽  
J P Renton ◽  
J McNally
Keyword(s):  
Embryo Transfer ◽  
Pregnancy Rates ◽  
Beef Heifers ◽  
Foetal Loss ◽  
Preliminary Results ◽  
Dairy Heifers ◽  
Embryonic Loss

In a recent study of the efficacy of two methods of oestrous synchronisation in dairy heifers, progesterone profiles and ultrasound results showed that late embryonic/early foetal loss had a small but nevertheless important effect upon pregnancy rates (Logue & others 1991). Since some preliminary results were available which showed that the use of a 3 mg norgestomet ear implant alone, rather than in combination with a 3 mg norgestomet and 5 mg oestradiol valerate injection (Crestar Intervet UK Ltd), enhanced pregnancy rates in beef heifers (Favero & others 1989) and the technique was being used in Embryo transfer (ET) recipients (Broadbent pers com) it was felt that a further investigation of the technique was merited.

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