Progesterone Interpretation


Natural or Fresh Semen:  Breed earlier in cycle (2nd, 3rd

                                           Day after ovulation)


Frozen Semen:  Breed later in cycle (4th day after ovulation)


        Anytime you have a value under 2.0 recommend retesting in 4 days.  This is to verify that the K9 did indeed pass 2.0 and progressed to ovulation/  Some females will remain below 2.0 for long periods of time before the LH peak

        Ovulation can be predicted with greater accuracy anytime you have >1 value at your disposal.  Always predict ovulation based on that days value, then go back and compare that to predictions based on previous days values

        If there is only one P4 value available, and it is high (ie >8), accurate prediction of ovulation is difficult.  If this is the case, the recommendation should be to breed as soon as possible, and repeat breeding until the bitch no longer stands.  Ultimately it should be advised to do vaginal cytology under these circumstances to determine if the bitch has already passed her fertile period.

        The guidelines for breeding are based on the following facts:


    Ovulation occurs 2 days after LH peak (P4=2.0)

    Newly release ova require 1-2 days to mature after ovulation

    After maturation, the ova have a viable life span of 72 hrs.


Value                                     Clinical Interpretation


< 1.7                                       Retest progesterone level in 4 days

1.7 1.8                                 LH peak should occur the next day

1.9  - 2.5                                 LH peak today, ovulation in 2 days

2.6 3.9                                 LH peak yesterday, ovulate next day

4.0 8.0                                 Ovulation today, breed 1st in 2 days

8.1 10.0                               Ovulation yesterday ?  breed next day *

10.0 12.0                             Breed now & EOD until out of heat *

12.0 _ 14.0                             Breed now & EOD until out of heat *


* Difficult to predict day of ovulation if this is the only test value available.

        Palpate between  21- 28 days

        Xray  After Day  55

        63 days from ovulation day for puppies are born

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