Academic literature on the topic 'Synchronization of ovulation'
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Journal articles on the topic "Synchronization of ovulation"
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Gibbons, John, and Leigh Anne Busbee. "Ovulation Synchronization in Sheep." Biology of Reproduction 81, Suppl_1 (July 1, 2009): 586. http://dx.doi.org/10.1093/biolreprod/81.s1.586.
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Kishida, K., T. Nishisouzu, S. Aoki, M. Iwata, O. Dochi, and H. Koyama. "337THE ONSET AND DURATION OF OVULATION IN DAIRY COWS SUPEROVULATED FOLLOWING SYNCHRONIZATION OF FOLLICLE WAVE WITH CIDR AND ESTRADIOL BENZOATE." Reproduction, Fertility and Development 16, no. 2 (2004): 288. http://dx.doi.org/10.1071/rdv16n1ab337.
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Determining the optimal time for AI of superovulated cattle is important for yielding acceptable fertilization rates. The objectives of this study were to determine the interval to onset, and the duration of ovulation in dairy cows superstimulated with FSH following synchronization of follicular wave emergence with a CIDR and estradiol benzoate (EB). Holstein (n=8) and Jersey (n=1) cows received an intravaginal progesterone insert (CIDR-B, InterAg, Hamilton, New Zealand) combined with an injection of 2mg EB at a random stage of the estrous cycle (Day 0). Superstimulatory treatments were initiated on Day 6 with a total dose of 24 or 36mg FSH (Antrin, Denka, Kawasaki, Japan) via twice-daily i.m. injections in decreasing doses for 4 days. At 72h after the first FSH injection, 30mg PGF (Pronalgon F, Pharmacia, Tsukuba, Japan) was administered, and CIDR-B were removed at 80h. Transrectal ultrasonography of ovaries was performed at 3-h intervals from 40 to 77h after the PGF injection. The numbers of ovulations were counted as previously described (Purwantara et al. 1994 Anim. Reprod. Sci. 37, 1–5). All detected follicles were counted and classified as small, medium, or large (diameter 2–4mm, 5–9mm, or ≥10mm, respectively). The number of ovulations recorded after each scanning was defined as the change in the number of large- and medium-sized follicles observed since the previous scanning. Data were analyzed using ANOVA. Results are presented in Table 1. There were two patterns of ovulations: one was a concentrated pattern of ovulations (ovulatory period <10h); the other was a prolonged pattern of ovulations (ovulatory period >10h). In cows with a high superovulatory response (≥14 ovulations), the onset of ovulation was earlier (P<0.05) and the duration of the ovulatory period was longer (P<0.05) than in cows with lower (≤8 ovulations) responses. In conclusion, concentrated and prolonged ovulation patterns were seen in dairy cows superstimulated after synchronization of the follicle wave with a CIDR and EB. In cows with a large number of follicles, the onset of ovulation tended to be earlier and the duration of the ovulatory period longer than in cows with fewer follicles. Table 1 The onset and duration of ovulation in dairy cows superstimulated following synchronization of the follicle wave with a CIDR and EB
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Aali, M., J. A. Small, G. Giritharan, N. Ramakrishnappa, K. M. Cheng, and R. Rajamahendran. "In vitro assessment of corpus luteum function in cattle following Ovsynch and CIDR ovulation synchronization protocols." Canadian Journal of Animal Science 84, no. 4 (December 1, 2004): 721–24. http://dx.doi.org/10.4141/a03-044.
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Non-lactating beef cows (N = 40) were used to determine in vitro production of progesterone by CLs collected on days 6–8, 13–15 and 19–20, following Ovsynch or CIDR ovulation synchronization protocols. Progesterone released by the CL tissues into the medium was measured after 1 h of incubation (control) and after 6 h of hormone treatments (LH, PGF2α or LH + PGF2α). In vitro progesterone production did not differ (P > 0.05) between Ovsynch and CIDR ovulation synchronization protocols. Pooled data, irrespective of ovulation synchronization treatments, showed interaction (P < 0.05) between hormone treatment and stage of CL. Key words: Corpus luteum, progesterone, cows, ovulation synchronization
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Ferraz, Priscila A., Mariana A. A. Silva, Bia S. S. Carôso, Endrigo A. B. Araujo, Thereza C. B. S. C. Bittencourt, Marcos Chalhoub, Rodrigo F. Bittencourt, and Antonio L. Ribeiro Filho. "Effect of eCG on the follicular dynamics and vascularization of crossbred cows with different circulating progesterone concentrations during synchronization of ovulation in an FTAI protocol." Pesquisa Veterinária Brasileira 39, no. 5 (May 2019): 324–31. http://dx.doi.org/10.1590/1678-5150-pvb-5520.
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ABSTRACT: This study aimed to evaluate the effect of treatment with equine chorionic gonadotrophin (eCG) on the follicular dynamics and function of crossbred cows with different circulating progesterone (P4) concentrations during synchronization of ovulation in a fixed-time artificial insemination (FTAI) protocol. To this end, 30 crossbred cows were submitted to a pre-synchronization protocol to ensure that all of them presented corpus luteum (CL) at the beginning of the protocol, and were evaluated by transrectal ultrasonography (TRUS) to verify the presence of CL. After that, the animals underwent an ovulation synchronization protocol and evaluation of follicular dynamics and vascularization by B-mode and power-Doppler ultrasound (US). High plasma P4 concentrations at the time of ovulation synchronization negatively influenced follicle diameter on day 10 (D10), preovulatory follicle diameter, and preovulatory follicle wall vascularization area (p<0.05). Cows with high P4 concentration at the time of ovulation synchronization that were treated with eCG showed follicle diameter on D10 and preovulatory follicle diameter and wall vascularization area (p>0.05) similar to those of animals with low P4 concentration at the time of ovulation synchronization. Therefore, high P4 concentrations at the time of ovulation synchronization negatively influence follicular diameter and vascularization, and eCG can be used as a strategy to favor better follicular and luteal response in crossbred cows with high P4 concentrations submitted to an FTAI protocol.
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Bruno-Galarraga, Macarena, Virginia Cano-Moreno, Beatriz Lago-Cruz, Teresa Encinas, Antonio Gonzalez-Bulnes, and Paula Martinez-Ros. "The Use of hCG for Inducing Ovulation in Sheep Estrus Synchronization Impairs Ovulatory Follicle Growth and Fertility." Animals 11, no. 4 (April 1, 2021): 984. http://dx.doi.org/10.3390/ani11040984.
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Currently, there is an intense effort to find an alternative hormone to eCG to induce ovulation after estrus synchronization treatments in sheep. One of the proposed alternatives is based on the use of hCG, but the results are controversial since fertility rates are commonly affected. The present study aims to evaluate, therefore, the adequacy of hCG in protocols for the synchronization of estrus and ovulation. Ovarian follicle dynamics, occurrence of estrus behavior and subsequent ovulation, quality of corpora lutea, and pregnancy rate after controlled natural mating were assessed in two consecutive trials. The findings indicate that the low fertility rates reported for the protocols based on the administration of hCG for inducing ovulation during estrus synchronization in sheep may be related to a high occurrence of abnormal follicular growth patterns, disturbances, and retardments of ovulation and concomitant formation of follicular cysts in the treated females. These results preclude their practical application to induce ovulation concomitantly to estrous synchronization treatments.
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Silva, Otávia Reis, Marco Roberto Bourg de Mello, Lara Nogueira Silenciato, Joaquim Esquerdo Ferreira, Samuel Rodrigues Bonamichi do Couto, Rosane Scatamburlo Lizieire Fajardo, and Osvaldo De Almeida Resende. "Comparison of estradiol benzoate and cypionate in Girolando cows submitted to a timed artificial insemination." Brazilian Journal of Veterinary Research and Animal Science 56, no. 3 (October 10, 2019): e155078. http://dx.doi.org/10.11606/issn.1678-4456.bjvras.2019.155078.
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The various studies on the manipulation of the estrous cycle culminated in the development of estrous and ovulation synchronization protocols, to the point of defining an optimum moment for artificial insemination. The induction of ovulation is a primordial part for the determination of the moment of the TAI, so to study which hormones and how they behave allows a better understanding of this physiological process and, to manipulate it efficiently. The aim of the present study was to compare the use of estradiol benzoate (EB) and cypionate (ECP) as ovulation inducer in Girolando cows submitted to Timed Artificial Insemination (TAI). Ovulations of 108 Girolando cows were synchronized and the initial day of treatment, recorded as D0, which was when the animals received an intravaginal device containing 1g of progestogen and an intramuscular application (im) of 2mg of EB. After 8 days (D8), the device was removed and 500μg of cloprostenol (im) was administered to all females. Then, the animals were randomly divided into two treatments: BG Group (n = 52) and CG Group (n = 56). The CG animals received 1mg of ECP (im) as the ovulation inducer at the time of device removal, while BG Group cows received 1mg of EB (im) 24 h later (D9). TAI occurred at D10. After device removal, ultrasound evaluations were performed every 12 h up to ovulation. The following reproductive parameters were evaluated: interval from intravaginal device removal to ovulation - IDO (hours); interval from ovulation to TAI-IOT (hours); diameter of the largest follicle at intravaginal device removal (mm); maximum diameter of the DF (mm) at D10; the dominant follicle growth rate (mm/day); synchronization rate - SR (%); ovulation rate - OR (%) and PR - pregnancy rate (%). Only the ovulation rate presented a statistical difference (p<0.05). In conclusion, despite the ovulation rate difference, both estradiol esters administered were effective and presented similar pregnancy rates in Girolando cows submitted to TAI.
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Martinez-Ros, Paula, and Antonio Gonzalez-Bulnes. "Efficiency of CIDR-Based Protocols Including GnRH Instead of eCG for Estrus Synchronization in Sheep." Animals 9, no. 4 (April 3, 2019): 146. http://dx.doi.org/10.3390/ani9040146.
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The present study examined, for meat sheep (Segureña breed; 2–5-years old, mean body score of 3.5 ± 0.5), the timings of onset of estrus behavior, preovulatory luteinizing hormone (LH) surge and ovulation, and the ovulation rate and fertility obtained after insertion of controlled internal drug release (CIDR) devices for 5 days plus treatment with equine chorionic gonadotrophin (eCG; single dose at CIDR removal, n = 19 ewes) or gonadotrophin-releasing hormone (GnRH, either in a single dose at 56 h after CIDR removal, group CIDR-GnRH, n = 19 ewes; or in one dose at CIDR insertion and another dose 56 h after CIDR removal, group GnRH-CIDR-GnRH, n = 19 ewes). In all the ewes, the appearance of estrus behavior ranged between 84% and 90% and all females showing estrus signs had subsequent preovulatory LH peaks and ovulations. Onset of these events was earlier in the CIDR-eCG group than in the CIDR-GnRH and GnRH-CIDR-GnRH groups (p < 0.05). These differences were mainly determined by the onset of estrus behavior, since timing and intervals of LH peak and ovulation were similar among treatments. In fact, the range of ovulations was narrower in the GnRH-CIDR-GnRH group, which suggests better synchronization of follicular growth (p < 0.05). In conclusion, protocols with two doses of GnRH offer similar yields to eCG protocols.
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Stuhr, Bhárbara Delboni, Isaac Santos Gil, Tracy Ferreira Lacerda, Mauricio Gomes Favoreto, and Bárbara Loureiro. "Consequences of eight consecutive applications of equine chorionic gonadotropin on ovarian follicle development and ovulation in bos indicus cows." Ciência Rural 46, no. 11 (August 15, 2016): 2018–23. http://dx.doi.org/10.1590/0103-8478cr20160091.
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ABSTRACT: The equine chorionic gonadotropin (eCG) is a glycoprotein produced in mare endometrial calices. In bovine, it is used in estrus synchronization protocols. However, studies have shown that it is potentially immunogenic and its effect can decrease after repetitive use. This study aimed to evaluate antral follicle dynamics, corpus luteum (CL) and ovulation rate in bos indicus cows submitted to an estrus synchronization protocol in association with eCG for eight times consecutively. Ten cyclical, multiparous, and pasture raised beef cows were divided into two groups: control group (n=5) and eCG group (n=5). In 30 day interval, all animals were synchronized with the same estrogen/progesterone based protocol, totalizing 8 re-synchronizations. Cows in the treatment group received 300IU eCG 48 hours prior to the presumable ovulation. Ultrassound examinations were performed on Day 4 of the protocol (approximately 1.5 days after follicle recruitment) to count antral follicles, on Day 10, to count antral follicles and to measure size of the largest follicle and on Day 18 to measure the diameter of the CL. No difference (P>0.05) between follicular growth and size of the pre-ovulatory follicle was reported between groups. Cows treated with eCG had a larger (P<0.05) CL and increased (P<0.05) ovulation rate (18mm and 92%, respectively) when compared with control group (14.1mm and 80%, respectively). Furthermore, consecutive treatments did not affect CL nor ovulation rates. In conclusion, eCG treatment increased CL size and ovulation rate even after 8 consecutive treatments.
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Brogliatti, G. M., H. Lagomarsino, and G. P. Adams. "Follicle ablation for ovulation synchronization in cattle." Theriogenology 49, no. 1 (January 1998): 339. http://dx.doi.org/10.1016/s0093-691x(98)90692-6.
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Wiltbank, Milo C., and J. Richard Pursley. "The cow as an induced ovulator: Timed AI after synchronization of ovulation." Theriogenology 81, no. 1 (January 2014): 170–85. http://dx.doi.org/10.1016/j.theriogenology.2013.09.017.
Full textDissertations / Theses on the topic "Synchronization of ovulation"
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Peeler, Iris Dawn. "Synchronization and Resynchronization of Ovulation and Timed Insemination in Lactating Dairy Cows and Heifers." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/9880.
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This study was conducted to evaluate the efficacy of intravaginal progesterone (P4) inserts (CIDR) in synchronization protocols combined with timed artificial insemination (TAI) as related reproductive performance. In the first study, heifers were synchronized with CIDR inserts followed by TAI. Heifers in the estradiol cypionate (ECP) group were synchronized with a combination of ECP, CIDR, prostaglandin (PGF2α), and ECP (CIDR-ECP), while the gonadotropin-releasing hormone (GnRH) group was synchronized using a combination of ECP, CIDR, PGF2α, and GnRH (CIDR-GnRH). All heifers were bred at either 48, 56, or 72 hours (h) after CIDR removal. Overall pregnancy rate (PR) for synchronized heifers was 60.1%, and embryo survival rate (ESR) was 98%. Pregnancy rate for CIDR-ECP treated heifers was influenced by artificial insemination (AI) time. In conclusion, ECP or GnRH may be used effectively in a CIDR-based TAI program in heifers. In the second study, cows were synchronized with CIDR devices or Ovsynch. The CIDR group received a combination of ECP, CIDR, PGF2α, and GnRH, while the Ovsynch group was synchronized using a combination of GnRH and PGF2α. Cows were bred at either 0, 8, or 24 h after the final GnRH injection. Overall PR for first service was 30.5% with ESR of 82.8%. Overall resynchronization PR was 35.1% with an ESR of 84.8%. In conclusion, Ovsynch and CIDR-based protocols are equally effective in synchronizing ovulation in a TAI program and resulted in comparable PR.Master of Science
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Stutts, Kyle Jeffrey. "Synchronization of follicular wave emergence, luteal regression, and ovulation for fixed-time artificial insemination in beef cows and heifers." Texas A&M University, 2005. http://hdl.handle.net/1969.1/4208.
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Two experiments tested the efficacy of gonadotropin-releasing hormone
(GnRH) or estradiol cypionate (ECP) administration in combination with
controlled internal drug release (CIDR) inserts on pregnancy rate to fixed-time
artificial insemination (FTAI) in beef heifers. In the first experiment, heifers in the
two ECP groups received ECP in conjunction with the CIDR insert. The CIDR
insert was removed and PGF was administered on either d 7 or 9. Heifers
received ECP 24 h after CIDR removal and were inseminated 30 h after ECP.
Heifers in the two GnRH groups received GnRH in conjunction with the CIDR
insert. Heifers received PGF on either d 6 or 7, and the CIDR insert was
removed on d 7. Heifers were inseminated and received GnRH 48 h after CIDR
removal. Pregnancy rates to FTAI were higher for heifers treated with GnRH.
Pregnancy rate to FTAI was highest for heifers in the GnRH group that received
PGF on d 6 and was lowest for the group that received ECP in combination with
a 7-d CIDR insert. In the second experiment, heifers received GnRH in conjunction with the
CIDR insert. CIDR inserts were removed and PGF was administered on d 7.
Heifers were inseminated 60 h later, with one group receiving GnRH at
insemination. Pregnancy rate to FTAI was higher for heifers that received GnRH
at insemination.
The final experiment tested the efficacy of estradiol 17_ (E17) or GnRH in
combination with a CIDR insert on pregnancy rate to FTAI in Brahman cows.
Either E17 or GnRH was administered in conjunction with the CIDR insert.
CIDR inserts were removed on d 7. Cows in the GnRH group received PGF on
d 6 and GnRH at insemination which occurred 48 h after CIDR removal. Cows
in the E17 group received PGF on d 7, E17 24 h later, and were inseminated 30
h after E17 administration. Pregnancy rate to FTAI was higher for cows treated
with E17.
These data indicate acceptable pregnancy rates were obtained when the
CIDR insert was combined with either GnRH in beef heifers or with E17 in
Brahman cows.
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Cline, Mark Andrew. "Efficacy of Synthetic Gonadotropin Releasing Hormone Analogs for Control of Ovulation During Estrus Synchronization Protocols." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/31372.
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Two experiments were conducted to determine efficacy of GnRH analogs, Cystorelin (CYS, gonadorelin diacetate tytrahydrate) and Factrel (FAC, gonadorelin hydrochloride), for use in beef timed AI synchronization. In Experiment one 342 beef cows from 7 herds were assigned CYS or FAC treatment as part of the Ovsynch protocol (GnRH d 0 and 9, Lutalyse d 7). Cattle treated with FAC had greater tendency (P=.09) to be pregnant at d 45. One individual herd demonstrated FAC-treated cows had more pregnancies at day 45. In Experiment two, 18 beef cows received either CYS or FAC as part of the Ovsynch protocol, intensive blood samples, from time -30 to 525 min post GnRH, were collected at each GnRH injection. Ultrasounds were conducted daily over the course of the protocol. A treatment by phase interaction (P=.03) was found for the time to maximum LH concentration, where CYS-treated follicular cows had a shorter interval than did FAC treated follicular or luteal cows. The duration of detectable LH response showed a treatment by phase interaction (P = .02) where follicular and luteal CYS-treated cows had shorter interval than follicular or luteal FAC-treated cows. The variables maximum LH concentration, and area under LH curve did not differ. Cows treated with CYS had more (P=.02) non-dominant follicles. In Experiment three, 16 ewes randomly received either CYS, FAT or Fertagyl (FER; gonadorelin diacetaate tytrahydrate), and FAT's induced LH maximum concentration occurred sooner (P=.02) than CYS. We conclude that either product may be used in beef cows without compromising fertility.Master of Science
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Gordon, Miriam Bronwen. "Strategies to improve ovulation synchronization/timed artificial insemination protocol to increase pregnancy rate in dairy cattle." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/37788.
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Physiological stressors of high milk production and intensive management systems affect fertility and pregnancy rates (PR) in lactating dairy cows. A field study was conducted on dairy farms in the Fraser Valley of British Columbia to benchmark current reproductive performance and issues that impact local dairy farms. The results indicated a substantial reduction in reproductive performance due to inaccurate estrus detection, fertilization/ovulation failure, and embryonic mortality. Ovsynch timed artificial insemination (TAI) protocol is used for the induction and synchronization of ovulation in cattle, reducing the need for estrus detection. However, PR to Ovsynch TAI are still low. Strategies to modify Ovsynch TAI protocol were investigated in this study to increase PR. In the first experiment, Ovsynch was compared with a pre-synchronization treatment, using PGF₂α before Ovsynch TAI to improve synchronization rates, and to a treatment of GnRH given 6 d after Ovsynch TAI, to reduce embryonic loss. Although no differences in PR were observed between treatments, days in milk in cows and age and weight in heifers affected PR. In the second experiment, the effects of pLH or hCG vs. GnRH in an Ovsynch TAI protocol were compared. Progesterone concentrations in pregnant cows were greater in the hCG group on days 7, 11, and 14, and greater in the pLH group on day 11 after breeding than GnRH group. There were no differences in synchronization rates or PR between treatments. High protein diets have been associated with reduced PR. Therefore, in the third experiment, cows either continued on a typical high protein diet, which was fed from calving, or switched to a lower protein diet, beginning 7 d before Ovsynch TAI and continued until pregnancy diagnosis. First and second lactation cows fed the low protein diet tended to have greater PR than cows fed the high protein diet. There were no differences in synchronization rates and progesterone concentrations between diets. Cows fed the lower protein diet had lower milk urea nitrogen and lower average daily milk production during treatment. Costs associated with treatments, labour, and producer compliance should be considered before recommending ovulation synchronization Ovsynch TAI protocol to dairy producers.
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Buttrey, Brad Sterling. "Human chorionic gonadotropin and gonadotropin-releasing hormone influence pregnancy survival and resynchronized ovulation before timed artificial insemination in Holstein cattle." Thesis, Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/542.
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Mpoyo, Robert Kabyla. "Effects of different estrus synchronization and superovulation treatments on ovarian response and embryo collection in the South African Boer goat." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/70201.
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Thesis (MSc)--Stellenbosch University, 2004.Full text to be digitised and attached to bibliographic record.
ENGLISH ABSTRACT: Different synchronization and superovulation treatments were evaluated in the South African Boer goat (n = 367). Two progestagen implants, Synchro-Mate-B (SMB)/Crestar™ and Controlled Internal Drug Releases (CIDR), containing 3mg norgestomet and 0.33gm of natural progesterone, respectively, were used in the synchronization treatments. A luteolytic agent, Estrumate (Cloprostenol) 125)lg, was administered 12h before progestagen withdrawal. Synchronization treatment groups were: 1) 5MB x 1 (n = 123), one dose of 5MB for 13 to 17 days; 2) 5MB x 2 (n = 32), two doses of 5MB implanted for 10then 17 days; 3) CIDR x 1 (n = 187), one dose of CIDR; 4) CIDR x 2 (n = 25), two doses of CIDR, inserted for 9 to 17 days. On day 1 of the treatment, 0.5mg of estradiol cypionate (ECP) was administered to a group of randomly chosen goats (n = 112). Superovulation treatments consisted of Ovagen ™ or Embryo-STM. An additional single dose (300 UI) of Pregnant Mare Serum Gonadotropin (PMSG) was administered to a group of randomly chosen does. Superovulation treatment groups were: 1) OV alone (n = 147), Ovagen 9 mg every 12h, 8 times starting 72h prior to progestagen removal; 2) OV + PMSG (n = 164), same treatment as 1 plus 300 ru ofPMSG once 48h prior to progestagen removal; 3) E-S alone (n=16), Embryo-S 25 units twice a day, 8 times starting 72h before progestagen removal; 4) E-S + PMSG (n=40), same treatment as 3 plus 300 ru of PMSG once 48h prior to progestagen removal. Most does were naturally bred to bucks. Embryos were collected using the surgicallaparascopic procedure on day 6 and corpora lutea counted. Data were not normally distributed and therefore analyzed using a nonparametrie test (Wilcoxon, 1945 and Kruskal- Wallis, 1952) with outcome variable using the Mixed Procedure of SAS and the Tukey test. Differences were considered significant at p<0.05. Slightly more CL were on the left (52%) than on the right (48%) ovary. Superovulation treatment was significantly associated (p
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Pulley, Stephanie Leeann. "Hormonal responses and pregnancy outcomes after five-day ovulation synchronization and presynchronization programs in lactating dairy cows." Diss., Kansas State University, 2014. http://hdl.handle.net/2097/18266.
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Doctor of PhilosophyDepartment of Animal Sciences and Industry
Jeffrey S. Stevenson
Two experiments assessed pregnancy outcomes (pregnancy per AI; P/AI) after 5-d Ovsynch-56 Resynch (RES; GnRH injection 5 d before [GnRH-1; d 0] and 56 h (GnRH-2) after the last PGF2α [PGF] injection on d 6 given 24 h after first PGF injection on d 5, and TAI on d 8) with and without a 5-d progesterone insert. In Exp. 1, only 76% of 1,023 nonpregnant cows enrolled on d 34 post-AI had high (≥1 ng/mL) progesterone. The RES-CIDR cows with low progesterone at treatment initiation had greater P/AI than RES-CON (37.7 vs. 29.4%), whereas RES-CIDR cows with high progesterone had lesser P/AI than RES-CON (27.4 vs. 34.3%) suggesting that supplemental progesterone is progesterone-dependent. In Exp. 2, 381 cows were enrolled in similar treatments on d 31 with RES on d 41post-AI plus a third treatment including PG-3-G (Pre-PGF on d 31, Pre-GnRH on d 34, and RES on d 41. The P/AI was similar among treatments but was greater in cows starting RES on d 41 when progesterone was low (44%) than high (33%).Experiment 3 determined LH and ovulatory responses in cows enrolled in two treatments before AI: 1) Pre10 (n = 37): PGF-1 and PGF-2 given 14 d apart (Presynch); or PG3G (n = 33): PGF given concurrent with the PGF-2, 3 d before GnRH-1 followed in 7 d by Ovsynch [injection of GnRH (GnRH-2) 7 d before PGF (PGF-3) and GnRH-3 at either 56 or 72 h after PGF-3] that was initiated 10 d after PGF-2 for Pre10 or 7 d after GnRH-1 of PG3G. The GnRH- 1 increased incidences of LH surges and ovulation in PG3G compared with Pre10. The LH in serum of Pre10 was greater than that of cows receiving PG3G after GnRH-2. Following GnRH- 3, cows receiving GnRH at 72 h had increased incidence of spontaneous LH surges before GnRH-3. The P/AI for PG3G vs. Pre10 and for 56 vs. 72 h was similar, but the Pre10-72 h treatment combination was less than all other treatment combinations. Release of LH is protocol dependent and flexibility of GnRH timing is an advantage for PG3G before first-service TAI.
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Reway, Ana Paula. "Desenvolvimento de protocolo de sincronização da onda folicular e determinação do momento ideal para indução da ovulação na espécie equina." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/10/10132/tde-30032017-101852/.
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Foram realizados cinco experimentos com o objetivo de sincronização do estro e indução da ovulação em tempo fixo em éguas. Experimento I: avaliou a eficácia de um novo protocolo hormonal para a sincronização do estro, sendo realizado durante o período transicional em éguas cujo status reprodutivo era desconhecido. Experimento II: foi delineado para determinar o momento ideal para retirada dispositivo intravaginal de progesterona (DIP), sendo o dispositivo retirado no dia 7, 8 ou 9 do protocolo de tratamento hormonal. Experimento III: testou se a eficiência do protocolo é dependente da fase do ciclo estral da égua e definiu o melhor momento para indução da ovulação. Experimentos IV e V: as éguas foram submetidas ao protocolo completo de sincronização da onda folicular e indução da ovulação em diferentes fases do ciclo estral ou com status reprodutivo conhecido. A hipótese testada foi de que a sincronização do estro e indução da ovulação, com o uso do DIP de 1,44g provoca a supressão do crescimento folicular e através da indução da ovulação, com hCG e GnRH, promove a ovulação dentro de 42 ± 6 horas de no mínimo 75% dos animais. Para isso, os efeitos das prostaglandinas e progestágenos foram avaliados quanto à capacidade de sincronizar a onda de crescimento folicular. Um novo tratamento para induzir a ovulação em tempo fixo foi testado com uma combinação de GnRH e hCG em dois momentos estratégicos (D10 e D12) visando maximizar o número de éguas ovuladas. O protocolo com administração de prostaglandina no D0, D6 e D8 juntamente com a colocação do DIP mantido durante 8 dias (D0 ao D7) demonstrou ser eficaz para suprimir a taxa de crescimento folicular em éguas cíclicas. Nas éguas submetidas a este protocolo as ovulações que ocorreram naturalmente se concentraram entre os dias 10 e 13 do tratamento. Foi testada a eficiência da indução da ovulação no D10 e D12. Na maioria dos animais tratados, o folículo pré-ovulatório foi responsivo à combinação de GnRH e hCG promovendo o sucesso da indução da ovulação. A eficiência do protocolo hormonal testado para sincronização do estro e da ovulação foi de 76,73%, sustentando a hipótese deste estudo. Novos estudos devem ser realizados em um maior número de animais para possíveis adequações na terapia hormonal e verificação do resultado em um grande número experimental de animais.Five experiments were conducted with the objective of estrus synchronization and fixed time ovulation induction in mares. Experiment I: evaluated the efficacy of a new hormonal protocol for estrus synchronization in mares whose reproductive status was unknown during the transitional period. Experiment II: was designed to determine the best time to remove the P4 intravaginal device (PID). The device was removed on day 7, 8 or 9 of the hormonal treatment protocol. Experiment III: tested if protocol efficiency depends on the stage of mares estrus cycle and indicated the best time for hormonal induction of ovulation. Experiments IV and V: mares were submitted to the full protocol of follicular wave synchronization and ovulation induction at different stages of estrus cycle or at known reproductive status. The tested hypothesis was that the estrus synchronization and induction of ovulation, using an PID of 1.44g, causes suppression of follicular growth, and ovulation induction using hCG and GnRH promote ovulation within 42 ± 6 hours of at least 75% of treated animals. The effect of prostaglandin and progestagens at specific times were evaluated for the ability to synchronize follicular wave. A new treatment to induce fixed time ovulation was tested with GnRH and hCG combination in two strategic moments (D10 and D12) to maximize the number of ovulated mares. Administration of prostaglandin at D0, D6 and D8 together with PID maintained for 8 days (D0 to D7) proved to be effective to suppress follicular growth during reproductive period. In mares submitted to this protocol, ovulation occurred naturally and concentrated between D10 and D13. The ovulation induction efficiency was tested at D10 and D12. Most of the animals had preovulatory follicle responsiveness to GnRH and hCG, promoting the success of ovulation induction. The efficiency of the tested synchronization of estrus and ovulation induction protocol was 76.73% and supported the hypothesis of this study. Further studies should be performed on a larger number of animals for possible adjustments in hormonal therapy and verification of the result in a large number of animals.
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Saldarriaga, Lopez Juan Pablo. "Ovarian and hormonal events during synchronization of ovulation and timed appointment breeding of Bos indicus-influenced cattle using intravaginal progesterone, GnRH and prostaglandin F2(alpha)." Texas A&M University, 2005. http://hdl.handle.net/1969.1/4733.
Full textAbstract:
Objectives were to 1) evaluate the use of the CO-Synch + CIDR (COS-C)
protocol for synchronization of ovulation and timed AI (TAI) in Bos indicus-influenced
cattle, 2) compare cumulative pregnancy rates after COS-C synchronization and TAI to
those in a traditional management (TM) scheme, and 3) evaluate specific ovarian,
hormonal, and estrual events associated with COS-C. The COS-C regimen included
insertion of a controlled internal drug release device (CIDR) containing progesterone
and injection of GnRH (GnRH-1) on day 0, removal of the CIDR and injection of
prostaglandin F2a
(PGF on d 7, and injection of GnRH (GnRH-2) and TAI 48 h later. In
experiment 1 (Exp. 1), 335 females were stratified by BCS, parity and d postpartum
before random assignment to COS-C or TM. An additional 96 females in which TM
controls were not available for comparison also received COS-C. Conception rates to
TAI averaged 39% (n = 266). Cumulative pregnancy rates were greater (P < 0.05) after
30 and 60 d of the breeding season in COS-C than in TM (n = 170 and 165 females respectively). In experiment 2 (Exp. 2), 100 postpartum (F1) females were stratified as
in Exp. 1 within four replicates (25 each) and assigned randomly to receive either COSC
or COS (no CIDR) treatment. No differences were observed between treatments and
all data were pooled. Percentages of cows ovulating after GnRH-1, developing a
synchronized follicular wave, exhibiting luteal regression to PGF, and ovulating to
GnRH-2 were 40, 60, 93, and 72%, respectively. In experiment 3 (Exp. 3), primiparous
(F1) heifers (n = 32) and pluriparous cows (n = 18) received the Select Synch + CIDR
synchronization regimen (no GnRH-2 or TAI). Mean intervals from CIDR removal to
estrus and ovulation, and from estrus to ovulation were 70 ñ 2.9, 99 ñ 2.8, and 29 ñ 2.2
h, respectively. Relatively low TAI conception rates (< 50%) were attributed to failure
of 40% of cattle to develop a synchronized follicular wave after GnRH-1 and to
inappropriate timing of TAI/GnRH-2. It may be possible to improve TAI conception
rates by delaying TAI/GnRH-2 to between 66 and 72 h, and by developing methods to
increase the number of ovulations after GnRH-1.
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Costa, AntÃnio Nelson Lima da. "SincronizaÃÃo do estro e da ovulaÃÃo em novilhas girolandas: comparaÃÃo entre os protocolos hormonais âcidr-bâ e âovsynch." Universidade Federal do CearÃ, 2006. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=1385.
Full textAbstract:
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel SuperiorAvaliou-se a eficiÃncia de dois protocolos de induÃÃo e sincronizaÃÃo do estro e da ovulaÃÃo (âCIDR-Bâ âOVSYNCHâ) em 90 novilhas acÃclicas da raÃa Girolanda. Os animais foram distribuÃdos em trÃs grupos, onde o primeiro (n=30) foi submetido ao protocolo âOVSYNCHâ, que consiste na aplicaÃÃo intramuscular (IM) de 1,0ml de GnRH, sete dias depois 2,0ml de prostaglandina F2a (PGF2a), 48h depois mais 1,0ml de GnRH e IATF 16h apÃs a segunda dose de GnRH. O segundo grupo (n=30) foi submetido ao tocolo âCIDR-Bâ, que consiste na introduÃÃo do implante intravaginal âCIDR-Bâ juntamente com a aplicaÃÃo IM de 2,0ml de benzoato de estradiol (BE), apÃs 8 dias à feita a remoÃÃo do âCIDR-Bâ e a aplicaÃÃo IM de 500UI de gonadotrofina sÃrica da Ãgua prenhe (PMSG) e 2,0ml de PGF2a, 24h apÃs à feita mais uma aplicaÃÃo IM de BE e IATF 30h depois desta aplicaÃÃo, ou seja, 54h apÃs a remoÃÃo do âCIDR-Bâ. O rceiro grupo (n=30), grupo controle, nÃo foi submetido a tratamento hormonal. Os diagnÃsticos de gestaÃÃes foram feitos 35 dias apÃs a primeira, segunda e terceira nseminaÃÃes artificiais (IA) por meio de ultra-sonografia (US). TambÃm foi avaliado o custo/benefÃcio de cada protocolo. O tratamento âCIDRBâ mostrou-se mais eficiente em primeira IA (p<0,05), assemelhando-se ao grupo controle com taxas de concepÃÃo e prenhez de 60 e 50%, respectivamente, demonstrando ter uma qualidade de estro comparÃvel ao natural. Na segunda IA, os tratamentos foram equivalentes nas taxas de prenhez, mas diferiram nas de concepÃÃo (96% âCIDR-Bâ e 76% âOVSYNCHâ). Deste modo, o protocolo âCIDR-Bâ mostrouse mais eficiente na induÃÃo da puberdade em novilhas girolandas com melhores taxas de concepÃÃo e prenhez em primeira IA, reduzindo onsideravelmente a idade ao primeiro parto. AlÃm disso, apresenta-se economicamente viÃvel com possibilidade de reutilizaÃÃo do implante, devendo-se atentar aos cuidados com higiene e manipulaÃÃo do produto.
Two oestrus and ovulation synchronization protocols (CIDR-B and OVSYNCH) were tested on 90 acyclical Girolanda heifers. The animals were distributed in three groups. Group I (n=30) was submitted to the OVSYNCH protocol, consisting of: intramuscular (IM) application of 1.0 ml gonadotropin-releasing hormone (GnRH), 2.0 ml rostaglandin F2a (PGF2a) after 7 days, 1.0ml GnRH 48h later, then timed artificial insemination (TAI) 16h after the second application of GnRH. Group II (n=30) was submitted to the CIDR-B protocol, consisting of: introduction of intravaginal CIDR-B implant and application of 2.0 ml estradiol benzoate (EB) IM, implant removal after 8 days, application of 500 UI pregnant mare serum gonadotropin (PMSG) and 2.0 ml PGF2a, a second IM application of BE 24h subsequently, then TAI 30h later (i.e. 54h following implant removal). Group III (n=30; control group) received no hormonal treatment. Gestation was verified ltrasonographically 35 days after the first, second and third AI. The cost-benefit ratio of each protocol was also determined: The CIDR-B protocol was most efficient in the first AI in which it was comparable to the control group in providing a near-natural oestrus quality (conception and pregnancy rates of 60% and 50%, respectively; p<0.05). In the second AI, the two treatments yielded similar pregnancy rates, but differed in conception rates (96% for CIDR-B; 76% for OVSYNCH). Thus the CIDR-B protocol was the more efficient in inducing puberty in Girolanda heifers, featuring the best conception and pregnancy rates in the first AI and considerably reducing age at first birth. It is moreover economically feasible as the implant may be reused provided apropriate care is given to hygiene and handling.
Book chapters on the topic "Synchronization of ovulation"
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Thatcher, W. W. "OESTRUS CYCLES, CONTROL | Synchronization of Ovulation and Insemination." In Encyclopedia of Dairy Sciences, 2178–84. Elsevier, 2002. http://dx.doi.org/10.1016/b0-12-227235-8/00424-7.
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PINTO, CARLOS R. F., and PATRICK J. MEYERS. "Control and Synchronization of the Estrous Cycle and Ovulation." In Current Therapy in Large Animal Theriogenology, 91–98. Elsevier, 2007. http://dx.doi.org/10.1016/b978-072169323-1.50013-1.
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Thatcher, William W., and Jose E. P. Santos. "Control of Estrous Cycles: Synchronization of Ovulation and Insemination." In Reference Module in Food Science. Elsevier, 2020. http://dx.doi.org/10.1016/b978-0-12-818766-1.00059-3.
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PURSLEY, JAMES RICHARD, and NORA M. BELLO. "Ovulation Synchronization Strategies in Dairy Cattle Using PGF2α and GnRH." In Current Therapy in Large Animal Theriogenology, 286–93. Elsevier, 2007. http://dx.doi.org/10.1016/b978-072169323-1.50041-6.
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VAUGHAN, JANE. "Ovarian Synchronization and Induction of Ovulation in Llamas and Alpacas." In Current Therapy in Large Animal Theriogenology, 884–89. Elsevier, 2007. http://dx.doi.org/10.1016/b978-072169323-1.50123-9.
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Thatcher, W. W., and J. E. P. Santos. "Reproduction, Events and Management | Control of Estrous Cycles: Synchronization of Ovulation and Insemination." In Encyclopedia of Dairy Sciences, 454–60. Elsevier, 2011. http://dx.doi.org/10.1016/b978-0-12-374407-4.00453-2.
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Joselin, Calderón-Luna, and Santos-Calderón Carlos. "Bibliographic Review of the Application of Ovulation Synchronization Protocol Based on Gonadotropin-Releasing Hormone (GnRH) and Insulin to Increase the Conception Rate in Crossbred Holstein Cows." In Estrogen. IntechOpen, 2019. http://dx.doi.org/10.5772/intechopen.85523.
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