Q. My standard poodle just started today a discharge thick and slimmy she is 12 years old
A. If the discharge is coming from her vagina , she has got an infection of her uterus. That is the most likely cause of vaginal discharge in an unneutered female dog. It is very important that you have her checked over by a vet or concenquences could be life threatening. It can be cured with supportive treatment ( IV fluids antibiotics and other medications ) and most likely surgery ( ovariohysterectomy ).
A. Have her examined by your veterinarian, especially if she is lethargic or feverish. If she is an intact older female, rule out pyometra (uterine infection).