Pelleted or block type diets are available for rats, and are formulated to be nutritionally complete. Choose a rat block that is low in fat and calories, and has soy meal high on the ingredient list rather than corn. While rat blocks should make the basic diet, a variety of fresh foods can be used to supplement the diet, which will aid in keeping rats healthy and prevent boredom with the pelleted diet. Packaged loose mixes are also available, but rats tend to pick out their favorite bits from the mix, which may mean they are not eating a balanced diet. Try small amounts of fruits and vegetables, whole grain pastas and bread, brown rice, yogurt, and occasionally low fat cooked meat, mealworms, cheese, seeds and nuts. In addition, treats such as dog biscuits can be given. It is important to keep rats on a high fiber and low fat diet though, so limit higher fat foods such as cheese, seeds, and nuts. Rats have a bit of a sweet tooth, but resist the temptation to feed sugary foods or junk food, including chocolate. More information on what to feed and what to avoid can be found in "Feeding Pet Rats."
Playtime Outside the Cage
Beyond providing the basics in food and housing, rats do not require much else except your attention and free time outside of the cage. Make sure that the area you allow your rats out in is rat-proofed since rats will chew on just about anything they can get their teeth on. Most importantly, make sure electrical wires are out or reach or encased in plastic tubing. Also make sure the rats cannot access anything that is toxic, including poisonous plants. Make sure anything you don't want your rats to chew is out of reach. Rats also tend to scent mark as they roam, leaving little drops of urine. The odor is not offensive, but you may want to cover furniture with a throw while they are out. They will also do this to their owners, so be prepared!
Rats have sharp little nails, and for your comfort when playing with your rats you may need to trim their nails. Check them every one to two months. Nail trimming is not difficult, escept that your rat will probably object and try to squirm away. You can use a pair of human nail clippers and trim a little off the tip if needed. Just take a tiny bit off the tip and avoid the pink part (quick) that may be visible inside the nail, as this is a blood vessel and nerve. If you do happen to nick the blood vessel, a little cornstarch applied to the nail tip should stop any bleeding (or you can by a product at the pet store called Kwik Stop that is used the same way).
At the same time you check the nails, try to get a glimpse of the teeth to make sure they are not getting overgrown. Make sure you provide lots of opportunity (through wood blocks and toys) for your rats to chew and keep their teeth healthy.
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