Diagnosis and therapy of the subinvolution of placental sites in the bitch.

Within the last 19 years, 20 cases of placentitis post partum have been studied at the clinic. On 14 occasions the condition took the form of excessive uterine bleeding (metrorrhagia) post partum and, on five occasions, of prolonged vaginal discharge lasting 8-13 weeks post partum. One bitch with a clinically undetectable form of this disorder was diagnosed at ovariohysterectomy. The average age of the bitches was 4.5 years (range 2-6 years). Examinations included abdominal palpation, vaginoscopy, vaginal smear examination and, if necessary, radiography and ultrasonography. The presence of decidua-like cells in the smear was confirmed as evidence of abnormal uterine involution. Six dogs were subjected to ovariohysterectomy; histological examination revealed inflamed and degenerated areas of the uterine surface. Decidualike cells were seen for up to 10 weeks post partum. Fourteen bitches were treated successfully with an injection of the progestagen Niagestin (25-50 mg per bitch) and both intrauterine and parenteral antibiotics were administered. The discharge stopped within a few days in all dogs treated. A subsequent normal pregnancy occurred in four cases.