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Updated: Jun 20, 2026
09:11
Isolation of Small Preantral Follicles from the Bovine Ovary Using a Combination of Fragmentation, Homogenization, and Serial Filtration
Published on: September 27, 2022
Follicular dynamics, ovulation and conception rates in bitches
G C W England1, M Russo, S L Freeman
1School of Veterinary Medicine and Science, University of Nottingham, Leicestershire, UK. gary.england@nottingham.ac.uk
Reproduction in Domestic Animals = Zuchthygiene
|September 17, 2009
Summary
This study used ultrasound to monitor canine follicle dynamics and reproductive success after estrus induction. Cabergoline treatment showed promising results, yielding follicle and corpus luteum numbers similar to natural cycles.
Area of Science:
- Veterinary Medicine
- Reproductive Biology
- Animal Science
Background:
- Understanding follicle dynamics is crucial for optimizing canine reproduction.
- Estrus induction protocols can influence follicular development and ovulation rates.
Purpose of the Study:
- To estimate follicle numbers, ovulation, and conception rates in bitches using real-time ultrasound.
- To investigate follicle dynamics following estrus induction.
- To compare the effects of different estrus induction methods on reproductive parameters.
Main Methods:
- Real-time ultrasound imaging was employed in a clinical study.
- Follicle populations were monitored during late anestrus and prior to the LH surge.
- Ovulation and conception rates were assessed.
- Estrus induction was achieved using gonadotrophin and cabergoline regimes.
Main Results:
- A shift from small to large follicles was observed approximately 2 days before the LH surge.
- High ovulation (97-100%) and pregnant rates (86-100%) were achieved.
- Cabergoline treatment resulted in follicle and corpus luteum counts similar to control cycles, unlike gonadotrophin treatment which produced non-ovulating small follicles.
Conclusions:
- Real-time ultrasound is effective for monitoring follicle dynamics and reproductive outcomes in bitches.
- Cabergoline appears to be a more effective estrus induction agent than gonadotrophins, promoting normal follicular development and ovulation.
- Estrus induction protocols significantly impact reproductive performance in canines.
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