Fontbonne, Alain (2008) In vivo ovulation, oocyte maturation and fertilisation in the bitch. PhD thesis Biologie de la reproduction, Ecole Nationale Vétérinaire d’Alfort, UMR 1198 Biologie de la Reproduction et du Développement, AgroParistech 2008AGPT0010 p.116.
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Abstract
Timing the day of ovulation as accurately as possible is considered by most authors as one of the
most important factor in order to determine when to inseminate bitches. This is especially important
when using frozen semen, due to the relatively short survival of frozen/thawed semen in the female
genital tract after artificial insemination.
In our study, we first tried to find the most accurate technique to determine the exact occurrence of
ovulation in the bitch. We hypothesized that ovarian ultrasound examination could be a reliable and
accurate method to determinate ovulation in bitches. Our aims were to try to detect ovulation by
ultrasound in different breeds and to evaluate the interests and the accuracy of such a technique,
compared with hormonal levels around ovulation. Our study confirmed that ovarian ultrasound was
an accurate technique for timing ovulation in the bitch. We also found that, although more accurate,
ovarian ultrasound examinations improved the accuracy of ovulation detection in only 15.3 % of
bitches compared with progesterone. Altogether, progesterone plasma concentrations appeared
fairly constant around ovulation, whatever the breed, and, as a whole, progesterone assays
appeared as a precise method to time ovulation.
Using ovarian ultrasound examinations as the reference technique to time ovulation in the bitch, we
then aimed to evaluate the precise kinetics of in vivo oocyte maturation in the bitch, as well as early
embryonic development. Furthermore, we wanted to check if, in vivo, spermatozoa were able to
penetrate oocytes still at immature stages. We found that the germinal vesicle (GV) stage was the
only one present until 44 hours after ovulation. The first metaphase II stage was observed at 54
hours. Various oocyte maturation stages were observed at the same time within each bitch.
Fertilisation occurred in most cases from 90 hours post-ovulation in mature oocytes (metaphase II).
In vivo penetration of immature oocytes by spermatozoa was extremely rare.
These fundamental results may lead to an improvement or a simplification in everyday veterinary
practice, especially for artificial insemination with frozen-thawed semen. Furthermore, a better
knowledge of the processes involved in in vivo oocyte maturation, fertilisation and early embryonic
development are important steps towards the improvement of reproductive biotechnologies in the
canine species.
| Item Type: | PhD Thesis (PhD) |
|---|---|
| PhD Supervisor: | Chastant-Maillard, Sylvie |
| Date: | 14 February 2008 |
| Board of examiners: | Farstad, Wenche and Luvoni, Cecilia and Guérin, Pierre and Fiéni, Francis and Driancourt, Marc-Antoine and Guillot, Jacques and Chastant-Maillard, Sylvie |
| Ecole Doctorale: | ED 435 AGRICULTURE, ALIMENTATION, BIOLOGIE, ENVIRONNEMENTS ET SANTE |
| Discipline: | Biologie de la reproduction |
| Collection (Fonds): | AgroParistech |
| Institution: | AgroParistech |
| Department: | Ecole Nationale Vétérinaire d’Alfort, UMR 1198 Biologie de la Reproduction et du Développement |
| Subjects: | 7. Life Sciences and Engineering |
| Uncontrolled Keywords: | Dog, Chien, Ovulation, Oocyte, Fertilization, Fertilisation, Bitom, Insemination, Ultrasound, Ultrason, Ovary, Ovaire |
| ID Code: | 4418 |
| Deposited By: | Marina Briffaut |
| Deposited On: | 04 December 2008 |
Table of content
Introduction 11
In vivo oocyte maturation, ovulation and fertilisation in the bitch : state of the
art 13
Chapter 1. Determination of ovulation 25
Chapter 2. In vivo oocyte maturation and fertilisation 69
Chapter 3: Optimal timing for artificial insemination with frozen-thawed
semen 83
Discussion and perspectives 89
General conclusion 96
References 97
Annex 1 107
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