There are two different mechanisms controlling sexual behavior – the male sex hormones and parts of the cerebral cortex. These systems are related because steroids, including the sex hormones, are thought to bind to the hypothalamic region and control both positive and negative feedback mechanisms for hormonal activity and sexual behavior.

It is important to note that there are large differences in the relative dependence of sexual behavior upon androgens and the cerebral cortex, both between species and between individuals within a species. In some dogs, sex drive is almost entirely dependent upon androgens, while in others the cerebral cortex plays the more dominant role. Hypersexuality is essentially excessive or aberrant sexual behavior, although it is sometimes also taken to encompass normal sexual behavior that is misplaced within modern society.

Signs of hypersexuality are:

– Agression;
– Mounting other dogs, people, inanimated objects;
– Territory marking, especially urination in the house;
– Roaming;
– Destructive behavior;
– Excitability, including excessive barking.

In a survey of 391 dogs presented at veterinary surgeries, 65% of dogs over 1 year old showed at least one of the signs noted above. A smaller percentage (52%) of dogs under 1 year old displayed such signs. Many of the dog owners stated that they were not concerned about seeking treatment for this behavior. This is possibly because this type of behavior is accepted as part and parcel of owning an entire male dog. In fact, some of these traits are normal in male dogs and it is merely a question of severity, frequency and place that makes the behavior unacceptable. Control methods tried in dogs with hypersexuality include castration, the use of sedatives, anti-androgens and behavioral modification/training.