Your female puppy knows that she isn't going to impregnate her favorite stuffed toy, but that won't stop her from pulling the old mount-and-hump. Her motivations for humping her toys are relatively similar to a male puppy's reasons and may be both psychological and physical.
It Feels Good
Untrained puppies live by principle: "If it feels good, do it." While female puppies don't mount as a way of procreating, they may find it's a pleasurable experience -- especially if you react to it, positively or negatively. According to the ASPCA, female puppies, whether or not they are old enough to experience estrus, or heat, may find that humping a toy gives them an enjoyable physical sensation. The behavior is more common in puppies and dogs that are in estrus.
Stress Response
When a puppy gets stressed out or overstimulated, she may have pent up anxious energy that she doesn't know how to get rid of. According to the ASPCA and Certified Professional Dog Trainer Jacque Lynn Schultz, she may find that furiously humping her stuffed toys is an excellent outlet for that pent-up nervousness. Monitor her behavior to see what triggers her humping sessions -- for example, she may go for it whenever company comes over, as being around new people is something to which she isn't yet accustomed.
Obsessive Compulsion
According to the ASPCA, a puppy can develop obsessive-compulsive disorder just like a human does, and humping is just one way that it manifests itself. An OCD puppy may compulsively lick things, walk in circles, drink water or hump her favorite toys. OCD frequently develops as a result of living in unideal conditions such as long periods of confinement, inadequate socialization or a poorly established daily routine.
Medical Concerns
Your veterinarian may be able to explain your female puppy's humping habit. According to the ASPCA, puppies and dogs may hump inanimate objects like stuffed toys in an attempt to alleviate the irritating symptoms of a medical problem. Allergic reactions, urinary tract infections and more can compel your puppy to grind away in a humping motion as she attempts to get relief from the irritation. Before seeking behavioral help from a trainer, get a checkup from the vet and voice your concerns.
Stopping the Behavior
According to the ASPCA and certified professional dog trainer Michael Baugh, to break the humping habit, you need to implement a two-part strategy of discouragement and prevention. For example, when your puppy starts to mount and hump, gently scold her and give her a command, like "Sit" or "Lay down." When she complies, reward her with praise and a treat. You may need to restrict her access to stuffed toys when you can't supervise her to ensure she doesn't revert to old habits when you aren't looking.
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Writer Bio
Tom Ryan is a freelance writer, editor and English tutor. He graduated from the University of Pittsburgh with a degree in English writing, and has also worked as an arts and entertainment reporter with "The Pitt News" and a public relations and advertising copywriter with the Carnegie Library of Pittsburgh.