Yes, like many mammals, dogs can experience what is colloquially referred to as “wet dreams” or nocturnal emissions. In the case of male dogs, this might involve involuntary ejaculation during sleep.
Male dogs, especially intact (non-neutered) ones, can experience physiological responses during sleep that lead to sexual arousal and release. Neutering a dog can influence reproductive behaviors, including the occurrence of such events.
If you observe unusual or persistent behaviors, it’s advisable to consult with a veterinarian to ensure there are no underlying health issues. In most cases, reproductive behaviors, including those during sleep, are a normal part of a dog’s life cycle and physiology.