Your two male cats look like prize fighters lately. Four-year-old Buster has been battling it out with five-year-old Rocky — and you haven’t seen a clear winner. They regularly thrash on the floor, rolling and spinning until one gets up and walks away. You know many cats engage in this play fighting behavior. You haven’t noticed any real aggression, so you haven’t broken up the warriors. When your scrappy feline housemates get annual physical checkups, your veterinarian explains what’s behind their frenzied antics:

Instinctive Feline Behavior

Buster and Rocky come from a long line of feline warriors. Their wild ancestors fed themselves by hunting, and used their defensive abilities to protect their territories. Although your pampered house cats no longer need those talents, they still have an instinctive drive to develop them. By engaging their feline housemates in play fighting, both cats get to sharpen their skills and make up afterward.

Excess Energy Burn

If Buster and Rocky were hunting prey every day, they’d likely expend considerable energy. Because they’re spoiled indoor cats, and you’ve conveniently provided them with top-quality food, they don’t need to engage in that behavior. That leaves your healthy boys with lots of energy to burn. Although they periodically race through the house and torment their toys, their sudden bursts of play fighting help to satisfy their need for vigorous movement.

Fighting Feline Boredom

With their daily needs met, your healthy adult cats need something to occupy their minds and bodies. They regularly explore the house, play with their toys, and watch “Animal Planet” shows on the big-screen TV. However, they might be looking for that extra-special activity that’s like the icing on the cake. Perhaps that’s where play fighting comes in.

Defending His Turf

With two blustery male cats in the same house, they’re bound to encounter some territory battles. Maybe Buster thinks Rocky is stealing his toys, scarfing his food, or taking over the prime sleeping spot. To put the marauder in his place, Buster engages in a vigorous round of play fighting.

When to Referee

If you see Buster or Rocky hissing, growling, or arching his back, their play fighting might have escalated to the next level. If the claws come out, someone could actually get hurt. To plan your response, contact your veterinarian for expert advice on breaking up the combatants.