Sexual Attractiveness in the Spayed Bitch
History. You are called by a veterinary colleague who has seen a bitch owned by one of her important clients. The client is upset because the dog is attracting males despite recently having undergone an ovariohysterectomy.
You inquire whether the dog allows intromission by males. Although the answer is “no," the owner is sure that a portion of an ovary was left in situ. Your colleague is sure she removed the ovaries during the surgical procedure. You are asked to examine the dog as a favor to your colleague.Clinical Examination. The dog has a vulva that is slightly swollen with a small amount of discharge present. An examination of a vaginal smear reveals some cornified epithelial cells but mainly an increased number of neutrophils. You indicate to the owner that you believe the male dogs are being attracted by the presence of an infection in the urogenital tract; the owner needs more convincing. You decide to obtain a reproductive endocrine panel (estrogen and progesterone) and a urinalysis from the dog. The values for both estrogen and progesterone are low and thus do not support the presence of ovarian tissue. The presence of white blood cells and bacteria in the urine suggests a urinary tract infection. A culture and sensitivity can be submitted to determine the specific bacteria and antibiotic sensitivity.
Comment. It is common for bitches with genitourinary infections to attract male dogs, presumably because of the odors generated by the infection. One of the most important points of differentiation as to cause (i.e., bladder infection vs. presence of ovarian remnant) is to know about the sexual behavior of the animal. The bitch allows intromission by a male only if she has been exposed to progesterone after priming with estrogen. This situation occurs only if an ovarian follicle is present and has begun to luteinize after the preovulatory luteinizing hormone surge. If the animal in question had allowed intromission, the presence of an ovarian remnant would be likely. Because of the failure of the bitch to allow intromission, you indicate that the animal almost certainly lacks ovarian tissue. With regard to the endocrine analysis, if the animal was completely Ovariectomized, both values will be low. This finding does not rule out the presence of ovarian tissue, but if the sample is obtained when the animal is showing the “sexual behavior,” it can be stated with assurance that the behavior is not caused by hormones or, by extension, activity of ovarian tissue.
Treatment. The bladder infection is treated, and the owner is instructed to keep the female away from males until the infection has cleared.