Determinatión of the Ovulatión


Vaginal Cytology

To determine the ovulation day is one of the most important points when managing canine reproduction.
There are three different ways of determining the ovulation time:
Vaginal cytology only valid for some bitches, very regular with the oestrous. Does not guarantee good results.


Progesterone test

Semiquantitative test progesterone

This is one of the best methods to determine the fertile days of the bitch. It is much more accurate than the vaginal cytology since many times there is no coincidence between the supposed ovulation time obtained by both different methods.
The test is done on serum or plasma, and the determination must be serial. It can be done with a quantitative test (we obtain an exact progesterone level) or a semiquantitative test were the progesterone value is determined within intervals. It is recommended to start with the progesterone tests on the days 5 or 6 after the first vaginal discharges of the bitch.


Ultrasound diagnosis of the ovulation time

Mature ovarian follicle

It is the third way of determining the ovulation day. Since 5 years we use this method in Cryocel to determine the optimal breeding day.
This is the surest way to determine on which days is conception assured. It must be done by veterinarians specialized on reproduction.
The ultrasound follow-up is serial and sometimes completed with a progesterone test. It is a pain-free method, that guarantees high success rates.
It is very useful for cases where the progesterone levels of the bitch at the ovulation time are not within the normal range, but the ovulation has not happened yet. It is recommended when we are going to use frozen semen or when the semen quality is not very good.


Different reports show that the bitch ovulates 48-72 hours after the increase in LH. The ovules cannot be fertilized until 48-60 hours after the ovulation and stay fertile for 48-72 hours. This is why it is important to do the progesterone determination when chilled or frozen semen is used.

Cryocel has Kits for Progesterone determination through quantitative methods for its clients and breeders.