Room to Hop
In research, the size of the cages in which rabbits are kept is important, but the way their living quarters are enriched is just as significant. In fact, an unfurnished cage is so boring for rabbits that it may cause them to develop behavioral pathologies such as stereotypical bar gnawing, tail biting and hair pulling. However, the rabbits in my care do not show any of these bizarre behaviors, probably because we do our best to provide them with living conditions suited for their species.
Rabbits are social animals. When given the choice, they clearly prefer to be in the company of another rabbit. Companionship is the best form of enrichment that we as caregivers can provide for our animals. All our female rabbits live in either pairs or small groups.
Sharing a large enclosure provides the individual rabbit substantially more space and hence possibilities for hopping and leaping that are lacking in small, standard single cages. We furnish each enclosure with a solid structure house that individual rabbits can flee to in the event of an alarming situation, or simply enjoy time on their own. An attached ramp makes it easy for the animals to climb onto the roof.
Rabbits like to dart into safe burrows. Rather than giving them PVC pipes, which are rather sterile and too hard for gnawing, we often place empty cardboard boxes into the cages. The rabbits love them. They hide in them and climb on top of them in order to have a good vantage point. Then they chew on them and finally destroy them. Cardboard boxes can create a big mess, but do not require extra time for keeping the cages clean. Milk crates, open transport cages, big plastic buckets and empty plastic drums sawed in half are other good alternatives. The rabbits do not lose interest in them, and they use them often as a quiet place for their siestas.
We use aspen wood shavings as bedding for our rabbits. It is not so much the shavings, but the empty big paper bags in which the shavings come that are the great attraction. I place a transport cage or bucket into the empty bag to keep it open, and the rabbits spend quite a bit of time hiding inside and chewing the heavy paper. They only stop once the bag has been completely chewed and flattened; one bag keeps the rabbits entertained for about two to three days. We also give them empty toilet paper rolls. Although I do not often see them playing with the rolls, they are usually chewed up into tiny pieces by the next morning.
Other play items I give my animals are empty water bottles filled with rocks or marbles, large plastic balls, shower curtain rings, Kong toys, rawhide chews and wood sticks. They do play with these objects, but usually for less than one hour daily. Often I find a toy at the very same spot that I placed it the day before during my next morning visit. Obviously, a toy lacks the responsiveness and ever-changing challenge of another rabbit companion, and therefore loses its attraction relatively quickly.
Some toys can entertain the rabbits quite a bit, while others receive hardly any attention. I have found over the years that my rabbits do not get tired of objects they can hide in or under, as well as chew and destroy. Objects that make a noise when being pushed around are interesting at first, but quickly lose their novelty. Individual rabbits seem to have favorite toys, but again, the interest is never long lasting. I like to give the rabbits toys on a rotational basis, exchanging them with different objects once a week when their cages are cleaned. This way, old toys regain some of their original attractiveness each time they have been removed for a while, cleaned and placed back into the rabbit cage.
Food for Fun
Food is also a great source of enrichment. My rabbits get fresh hay on a regular basis. Unlike with toys, I see no indication that the animals lose interest in this natural substrate promoting not only foraging, but also nest-building behavior. I sometimes give them a small (10 inches) or large (3 feet) branch. The rabbits seemingly enjoy stripping all the bark, but beyond that, they have little use for the branches. There are also little commercial rabbit toys that you jab fruit and veggies onto and hang from the sides of the cage, like a kabob. It is not very time consuming to prepare these toys and the rabbits like them.
Fresh fruit and vegetables are favorite treats. My rabbits love homemade dried fruit and whatever else I share with them. I only have to open the door of the room before all the rabbits approach me eagerly, waiting for their turn to get a treat. These regular, positive interactions with the animals have nothing to do with sentimentality, but they are a safeguard so the rabbits are not afraid of me, and will allow me to handle them during experimental procedures without getting distressed. The affectionate relationship with the animals in my charge is a basic condition so research data collected from them is not skewed by avoidable stress reactions.
Housing rabbits together, providing them with objects they enjoy and fostering an affectionate relationship with them is a simple but very rewarding task. It creates a humane living environment that promotes the well-being of the rabbits. After all, happy, healthy and relaxed rabbits make better research subjects and provide more reliable test results.