[Nancy1999]

Originally Posted by Mardelin

Here's my concern for an unspayed female that isn't used for breeding. Or even one that is used to breed, but has been decided to skip that particular breeding cycle. Pyometritis.

It can occur spontaneously, secondary to an infection (girls female organs are wide open during their Heat Cycle and suseptible to infection); as a post-partum (after whelping metritis, or mismating injection of estrogen,; as a post breeding or artificial insemination infection. This disease most commonly ocurs in bitches, starting at 3 to 4 years of age. The incidence increases with age and is increased in bitches with several nonpregnant cyles (false pregnancies resulting). Virtually every intact bitch can develop cystic endometrial pyometritis complex. Therefore, if they are not intended for breeding, they should be spayed prior to 3 years of age.

The "classic" signs of pyometra are increased water intake and urination, depression, and lethargy. Fever may be present, especially in advanced cases. Sometimes a vaginal discarge is present, sometimes not. Anytime a bitch is "off" after being in season, watch for these signs. The time varies, but observe roughly at two to three weeks. Usually it affects older bitches but can occur in younger ones. It can be very sneaky; the animal may become critical before the owner recognizes it is ill. Once diagnosed, it must be treated at once. Spaying is the best option. Waiting to treat with antibiotics can result in a ruptured uterus and a fatality.
An old adage in veterinary medicine is "don't let the sun set in a case of pyometria". Once you decide you will no longer be breeding your bitch have spayed as soon as possible.

I didn't realize girls were so vulerable at this time, I don't think I've ever read anything about this before. Anyway, it's another good reason to have your girl spayed.