“Should I get one rat, or two?”
That’s a question I hear asked very often, and, unlike most pet questions, it’s got an easy answer. Get two! Or, better yet, three, or as many rats as you have the time, space, and money to support! Rats are gregarious animals and need the company of their own kind in order to be happy. In fact, most good rat breeders require that babies be adopted in pairs.
In the wild, rats live in groups of hundreds. They are social animals that do not leave their colonies at adulthood, but simply expand their foraging radius and the size of their colony’s nesting area as the colony expands. Activities like play and social grooming help rats’ brains to develop. Studies have shown that social grooming is so important to rats that baby rats raised by a mother that does not lick and groom them grow up to be unfriendly and less intelligent than rats raised by a mother who is attentive.
In captivity, rats have been observed in a variety of social behaviors that suggest they may have the capacity for empathy and other “higher” emotions generally associated with humans and other primates. Some owners have reported that their rats buried dead companions in their bedding or stood guard over friends’ bodies until they were removed. Others have noted rats bringing food to sick cagemates. I even heard one owner swear that she had two rats who formed a monogamous bond and would not mate with others, even given the opportunity.
The variety of complex social behaviors present in rats makes clear that companionship enriches their lives. Single rats often display repetitive behaviors like chewing the cage bars due to boredom and loneliness. Some rats that suddenly are separated from companions and forced to live alone will become very ill. It is not unusual for a pair of elderly rats that were closely bonded to pass away within a few days of one another, often with the first rat’s death causing the second rat to refuse food or appear depressed and unwilling to continue living.
But my rat attacks others when I try to introduce cagemates!
Often, when a male rat has lived alone for some time, he will have difficulty accepting a new cagemate. Male rats can become territorial and display hormonal aggression. The simplest solution to either a lone male rat who won’t accept a cagemate initially or to a male rat who suddenly develops aggressive behavior towards his companions is to neuter the offender.
Normally, after about three weeks post-neuter, testosterone levels will have dropped off significantly and you will be able to successfully introduce the neutered male to cagemates. Three weeks is also the length of time necessary to ensure sterility, meaning at that point you can elect to have your boy rat bunk with the girls. Often, a male rat who has displayed aggression towards other males even when neutered will integrate easily with females.
My rat is already neutered, or is female, and is aggressive toward cagemates.
In rare cases, a male will remain aggressive after neutering, or a female will be aggressive toward other rats. Sometimes a pituary tumor is to blame, particularly if the aggression is sudden or if the rat also has other symptoms of a pituary tumor. Sometimes, the rat has simply been alone too long and is unable to form social relationships with other rats.
In the latter case, some owners have had success with gradual introductions spanning a period of weeks or months. It’s also possible to keep a lone rat, if that rat is determined to be alone and rejects cagemates. However, a single rat needs to to fill in for the social duties of a rat buddy. That means lots of attention and “grooming.” A human can simulate rats’ social grooming by stroking a single rat with a warm, damp washcloth. Lone rats need to spend more time out of their cages than rats with companions. An hour of exercise and attention out of the cage each day is the minimum for a lone rat’s happiness.
Of course, before deciding that your rat simply can’t accept companions, look first at your own role. Did you just toss another rat in the cage, or did you introduce them carefully in a neutral location like a bathtub? Did you repeat your attempt at introductions several times in neutral locations before caging the rats together? Did you try bathing both rats with the same gentle shampoo or Dawn dish detergent (safe for rats) before introducing them, to ensure that they would smell alike? If you could do a better job of introducing your rats, try that before resigning yourself to owning a lone rat.
Should I get my rat a same sex companion, or a neutered companion of the opposite sex?
I personally love mixed-sex colonies with all members of one gender or both genders altered. Mixed groups allow the owner to experience the advantages of both sexes and observe complex social interactions beyond those seen in single-sex groups. I have one cage holding three intact female rats and a neutered male, and I can’t help but giggle each time I see the 200 gram female, my smallest rat, flip the 700 gram neutered male on his back and forcibly groom him!
If you choose to create a mixed-sex colony, I recommend spaying all your female rats. Spaying reduces the risk of mammary tumors greatly, and eliminates the possibility of uterine cancer or pyometra (a life-threatening uterine infection). A spayed female can still develop a tumor, but compared to an approximately 50% risk of mammary tumors in intact females, the odds are much better. Spaying is more invasive than neutering, but females are also lighter-weight and tend to recover very quickly from surgery. I also know anecdotally of more males who have reacted poorly to anesthesia than females.
Rats are very sensitive to general anesthesia, and death is always a risk when surgery is performed. However, for most female rats, the benefits of a spay outweigh the risks. I would not have a female spayed over the age of one year unless medically necessary, due to the increased risk of complications with anesthesia.
Expect a spay or neuter for your rat to cost about the same amount as it would for a dog or cat. Sometimes rat surgery is even more expensive because of the difficulty of finding a vet experienced in operating on rats. You will usually spend $45-$200 on a spay or neuter, depending on your geographical location and what is included. Some vets include pain control and pre-anesthetic bloodwork in their pricing; others will quote the price only for the procedure, and anything else you want is extra.
If the cost or risks of spaying/neutering are unacceptable to you, you’re in good company. The majority of rat owners have single-sex groups, and there’s not a thing wrong with keeping only one gender. Your rat will not be missing out on anything if he or she isn’t able to interact with altered members of the opposite sex.