If I had to choose my favorite animal species, with apologies to my dogs, I would probably choose rats. However, I have not had pet rats for many years. When I was working with rats in the laboratory, pet rats were considered a risk, as you could spread diseases to the rats at work from your pets and wild rodents they might have unintended contact with. Also, I was moving around the world and while there are some systems in place to relocate between countries with dogs, doing so will rats is almost impossible. Added to that was my dog Avon, a stray from rural Scotland, was an ace killer of rats, mice and occasionally rabbits if he got the chance.

That said, on July 4, I glanced out the window and saw an emaciated hooded Norway rat wander across my deck. I captured her and acquired temporary food and housing. I told everyone that I was seeking whoever had lost this rat, or someone to adopt her. Knowing my fondness for rats, my friends were skeptical. And it became clear to me that rehousing a stray rat was not an easy thing to do, and the few local rescues were at a capacity dealing with surrendered rats and a number of unintended breeding and rat hoarding situations.

Thus I was presented, as an animal psychologist, with the job of safety integrated a rat into my household while considering the welfare of all of my dogs. Here are the basic steps I went through.

1. Safety

No dog meeting a pet rat for the first time can be considered totally ”safe,” and rats are also capable of doing serious damage if they feel threatened. Added to that, in this case, I had good reason to assume both my dogs would be likely to consider rats as food, not friends.

Many new small-pet owners need to calmly but carefully watch their dog’s reaction to ensure the dog does not take a prey interest in the new pet. Try not to make too many assumptions about your dog’s nature, as even the most benign canine might discover his inner coyote when confronted with small furry critters squeaking and rustling around. They may even seem to ignore them at first and have a sudden change in attitude after a few days when your small pet settles in and becomes more active, possibly while you are away from home.

For this reason I did not permit and any direct access between the dogs and rats. Some owners find that eventually their pets of different species can be allowed to interact, but I think it is best to take a cautious approach. I also acquired a properly sized rat cage with solid metal bars not more than a half inch apart. This meant that if I had any lapse in vigilance the dogs would not be able to easily get into the cage. When I was out of the home I placed the cage in an area the dogs did not have access to until I was confident that they would not bother it.

2. Welfare

Once it became clear that the rat, Piper, would be staying, I provided a properly sized environment with hiding places, climbing areas, an exercise wheel and daily handling and time outside the cage. I also met her social needs with the addition of two more rats in need of homes, Pipette and Pipsqueak. However, dogs can find the addition of small animals disturbing in various ways due to the new smells, sounds, and changes in household activities. For this reason, their responses need to be monitored and managed to ensure both types of pet are safe and not overly stressed.

3. Managed introduction

From the beginning, I watched how the animals were responding. I found that the rats and my Greyhound Vera paid very little attention to each other. Avon, predictably, showed some signs of frustration. The cage was positioned so he could not see it from his normal resting positions. Interrupting “rat staring” and rewarding resting did not resolve this frustration within a few days. So, it seemed a more gradual process would be required to move the rats from the “food” to the “irrelevant” category in his mind (“friend” not being a realistic goal, at least in the foreseeable future).

There are various way to do this, but in Avon’s case I took advantage of a 15-year-old dog’s declining sensory capacities. I left the cage in the living room but raised it above his standing eye level and interacted with the rats only minimally while Avon was present and awake. Using this approach his behavior returned to normal. And now I can remove and handle the rats and carry out routine care for them without him showing interest or disturbance. Both dogs show no significant response even when I remove a rat from the cage. For more vigorous or motivated dogs this process might need to be much more protracted, with rats and dogs being kept in different rooms either temporarily or even permanently. But others may find that dogs and small pets will become quite friendly with each other.

I still feel that keeping prey-motivated dogs and rats in the same household is less than ideal. However, in the face of limited alternatives, this situation can be safely accomplished by carefully considering how the small pets are housed and how dogs are managed to ensure they do not present a hazard to the small pet or find their presence disturbing.

Do you keep small pets as well as dogs? Please share your approach to ensuring they all get along!

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