Hormonal protocols for early resynchronization of ovulation in ewes: The use of progestagens, eCG, and inclusion of early pregnancy diagnosis with color Doppler ultrasound

Cosentino, Isabel Oliveira; Balaro, M. F. A.; Arashiro, E. K. N.; Santos, Juliana Dantas Rodrigues; Carvalho, Ana Beatriz da Silva; Clariget, Raquel Pérez; Ungerfeld, Rodolfo; Brandão, Felipe Zandonadi

doi:10.1016/j.theriogenology.2019.04.033

Cited by 20 publications

(21 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(2018) proposed a negative effect of MAP devices on P4 production in ewes (5.8 ± 0.5 ng/ml for control group vs. 4.7 ± 0.5 ng/ml for MAP group on Day 15), although without negative effects on the final percentage of pregnant females. A later study found no effect on P4 values either on pregnancy or luteolysis in sheep species (Cosentino et al., 2019). The results of the present study indicate that the use of a second P4 device does not imply negative effects on ovarian activity, since no difference was found between P4 values in does that received the second device and those which did not (G NPSP vs. G NPNSP or G PSP vs. G PNSP ).…”

Section: Discussionmentioning

confidence: 93%

“…In ewes, even though Miranda et al (2018) demonstrated a negative effect on P4 production, Cosentino et al (2019) did not.…”

Section: Introductionmentioning

confidence: 81%

“…(2018) demonstrated a negative effect on P4 production, Cosentino et al. (2019) did not. Both studies concluded that the use of a second progestogen device from Day 12 to Day 17 of the cycle had no effects on pregnancy or luteolysis, enabling its use in the early resynchronization protocol.…”

Section: Introductionmentioning

confidence: 93%

See 2 more Smart Citations

Early resynchronization protocols for goats: Progestogens can be used prior to an early pregnancy diagnosis without affecting corpus luteum functionality

Cosentino

Balaro

Leal

et al. 2020

Reprod Domestic Animals

Self Cite

View full text Add to dashboard Cite

Resynchronization protocols have been studied and successfully performed in cattle since the beginning of the century (Bartolome et al., 2005; Sani et al., 2011; Stevenson et al., 2003). With variations in timing and procedures, such protocols are primarily used to reduce the calving interval by inducing more synchronic ovulations during the breeding season. Hence, early resynchronization protocols are being studied to allow fixed time artificial insemination (FTAI) at intervals similar to the natural oestrous cycle (Palhão et al., 2020; Pugliesi et al., 2019), for which a new progesterone (P4) device should be inserted before the pregnancy diagnosis. The corpus luteum (CL) is a temporary endocrine gland of high importance in the maintenance of pregnancy, especially for goats, since ewes and cows can sustain late pregnancy without it (Casida

show abstract

Section: Discussionmentioning

confidence: 93%

“…In ewes, even though Miranda et al (2018) demonstrated a negative effect on P4 production, Cosentino et al (2019) did not.…”

Section: Introductionmentioning

confidence: 81%

See 1 more Smart Citation

Early resynchronization protocols for goats: Progestogens can be used prior to an early pregnancy diagnosis without affecting corpus luteum functionality

Cosentino

Balaro

Leal

et al. 2020

Reprod Domestic Animals

Self Cite

View full text Add to dashboard Cite

show abstract

“…The reported pregnant rates with cervical insemination range between 36 and 60% and depend on the deeply of semen deposition, the protocol, and time of insemination [22]. On the other hand, as described by Consentino [15], the use of color Doppler ultrasound to assess corpus luteum function increases the reliability of early pregnancy diagnosis, 28-day post-breeding, as it was performed in our study.…”

Section: Discussionmentioning

confidence: 56%

“…Transvaginal and transrectal B-mode ultrasound was used to pregnancy diagnosis [13,14] using Mindray ® Z5 Vet (Shenzhen, China) equipped with sectorial and transrectal 5-7.5 MHz probes. For pregnancy diagnosis, additional color Doppler ultrasound was used for the assessment of corpus luteum function [15]. The Doppler settings used were 20% color gain, 1.0 kHz pulse repetition frequency, 7 cm of depth, and 75 MHz wall filter.…”

Section: Assessment Of Pregnancy Outcomementioning

confidence: 99%

Pregnancy rates in hair sheep after Ovsynch synchronization and a combined intracervical fixed-time artificial insemination and 10-day mating period

et al. 2019

View full text Add to dashboard Cite

Aim: This study aimed to evaluate the pregnancy rates in hair ewes using an Ovsynch synchronization protocol under a breeding system that combines fixed-time insemination plus a 10-day mating period as an alternative. Materials and Methods: Through an experimental study (n=27), ewes were randomly located into one of three treatments: (1) Pre-synch (n=9): Prostaglandin F2α (PGF2α)+Gonadotropin-releasing hormone (GnRH)+PGF2α+GnRH; (2) Ovsynch (n=9): GnRH+PGF2α+GnRH; and (3) control: Ewes bred by natural mating (NM) (n=9). Ewes were fixed-time inseminated (fixed-time artificial insemination [FTAI]) with fresh semen, collected just before the insemination time through vaginoscopy at 16 h after the second GnRH (gonadorelin) injection. Each experimental group was placed separately during 15 days and, after this time, fertile rams were allowed back with ewes for a 10-day mating period. Control group ewes remained with the rest of the herd suitable for breeding and were bred under NM. Pregnancy diagnosis was performed by ultrasound at 28-, 56-, and 84-day post-breeding to differentiate between FTAI and NM pregnancies. Total (FTAI±NM) pregnancy rates at 56-day post-breeding were used to compared Pre-synch, Ovsynch, and control. For this purpose, two-tailed proportions comparison z-test was used with a 95% confidence level, for testing as the null hypothesis whether two proportions were equal. Results: Pregnancy rates were higher in control ewes (66.4%) than FTAI (46.6%). When pregnancy rates after a 10-day mating period (40%) were added, the final rate (86.6%) was significantly (p<0.05) higher in Ovsynch-based protocols. The pregnancy rate was significantly lower in FTAI ewes compared to FTAI +10-day mating group (p<0.05). The overall pregnancy rate was 88.0, 85.7, and 67.0 (p>0.05) for Pre-synch, Ovsynch, and control ewes, respectively. Conclusion: These results provide evidence on the benefits of combined FTAI protocols for improving the reproductive efficiency of sheep.

show abstract

Impact of Sex Steroids on the Stress Response and Welfare in Female Farm Ruminants

Freitas‐de‐Melo

Ungerfeld

2022

Sustainable Agriculture Reviews

View full text Add to dashboard Cite

Hormonal protocols for early resynchronization of ovulation in ewes: The use of progestagens, eCG, and inclusion of early pregnancy diagnosis with color Doppler ultrasound

Cited by 20 publications

References 14 publications

Early resynchronization protocols for goats: Progestogens can be used prior to an early pregnancy diagnosis without affecting corpus luteum functionality

Early resynchronization protocols for goats: Progestogens can be used prior to an early pregnancy diagnosis without affecting corpus luteum functionality

Pregnancy rates in hair sheep after Ovsynch synchronization and a combined intracervical fixed-time artificial insemination and 10-day mating period

Impact of Sex Steroids on the Stress Response and Welfare in Female Farm Ruminants

Contact Info

Product

Resources

About