On an episode of “It’s Me or the Dog,” a show on Animal Planet, British dog trainer Victoria Stilwell tackled the problem of a bull terrier that exhibited mounting behavior. The first solution was to send the dog for a time-out when he mounted. However, the mounting was so severe that the trainer finally recommended neutering, which solved the problem. This case raises two questions: What other behavioral issues can neutering help address, and what is the rate of success? In general, it would be expected that spaying or neutering most likely affects sexually dimorphic behaviors — those that are