Healthy Rat Diet

A Healthy Rat Diet (May 2007) … by Carole Nelson

with permission from Lil Ratscals Rattery (

A proper diet is essential for your rat’s good health. Rats are omnivorous, which means they eat both plant and animal material. Please do not try to convert your rats into vegetarians. They need animal protein, and cannot live on plant protein alone. Rats love food in general and will eat almost anything you put in front of them, savoring every morsel. They seem to eat when bored, even when sick or just for something to do. Rats love junk food just like us. Try to keep their diet as healthy as possible. Stay away from sugar. There are many healthy treats that you can offer your rats. Eating the same thing every day can also become boring just as it does for people. Hopefully I can give you some ideas on how to add some variety in their diet, while keeping them healthy at the same time.

Most commercial rat foods are unhealthy and should not be fed to rats. Most contain harmful additives, waste foods and chemical preservatives. Some contain (whole kernels of)* corn that could even contain fungus and mold, tiny seeds and also alfalfa pellets which are hard for rats to digest and they usually don’t care for it any way. Some rabbits have been known to develop a condition called “Sludge” if fed too much alfalfa.

Rats should be fed a good “lab-block” not dog or cat food. Lab-blocks are a complete nutritional diet that meets the nutritional requirements of rats. Assorted vegetables and fruit should be provided at a minimum 3 times a week. Lab-blocs are hard food made especially for rats. You can usually find them in most pet stores or feed stores. Lab-blocks, such as Harlan Teklad, Hagen Nutri-blocks, Oxbow or Mazuri, should be the main staple of your rat’s diet. They also keep their teeth from becoming overgrown.

Now you must try to keep protein levels within healthy limits. Protein range should be around 16 to 18 percent. Pregnant or nursing females as well as babies up to 13 weeks old can be fed a higher protein ratio. If rats are fed too much protein this can lead to protein scabs as well as excess orange looking grease on the skin of males.

If you notice that your males has too much grease, and it’s taking away from his natural beauty, you need to cut down on the level of protein in the diet. Try adding more grains and pasta to his diet and bathing them in Palmolive or Sunlight antibacterial dish detergent and it will also help cut this grease.

My rats also receive a grain mix which includes but is not limited to:

  • dry vegetable pasta twists (beet, spinach, tomato, carrot and squash)
  • 3/4 green split peas mixed with 1/4 yellow split peas
  • large natural oats
  • “Cheerios”, “Rice Krispies” and Corn Bran cereals
  • pumpkin seeds – raw, unsalted
  • dried cranberries or dried blueberries
  • fresh fruits may include but are not limited to:
    • strawberries
    • grapes (seedless)
    • bananas
    • pears
    • apples
    • oranges (only for does, which helps protect against cancer, NOT FOR MALE RATS)
    • watermelon
    • cantaloupe
    • kiwi fruit
    • papaya
    • raisins
    • avocado
    • tomatoes
    • nectarines
    • peaches
    • plums
    • honeydew melon
    • mango
    • blueberries

Please make sure to remove the pits from any fruit. Do not feed the skin on avocados.

Fresh vegetables include but are not limited to:

  • squash
  • mustard greens
  • collard greens
  • romaine lettuce
  • spinach
  • cucumber
  • alfalfa sprouts
  • zucchini
  • pumpkin
  • asparagus
  • broccoli
  • cauliflower
  • brussel sprouts
  • carrots
  • celery
  • fennel
  • sweet potato, yams (cooked. DO NOT feed raw!)
  • and sometimes cooked corn on the cob

Too much fruit or roughage can lead to diarrhea. Some vegetables such as asparagus, broccoli and cauliflower can cause gas so feed in moderation. 

Occasional treats:

  • rice cakes
  • cheese
  • baby food
  • mixed baby cereal
  • chicken bones
  • dog biscuits
  • soya milk
  • fish sticks
  • cooked rice and pasta
  • active yeast cultured yogurt (contains good bacteria that aids digestion)
  • cooked pasta and rice

Whole protein sources:

  • chicken
  • beef
  • tuna
  • salmon
  • oysters
  • shrimp
  • liver

What NOT to feed:

  • too much cheese (use a tiny bit as a treat)
  • too much peanut butter can cause a rat to choke and they cannot vomit. They lack the necessary muscles that would allow them to do so.
  • dried corn (can cause liver cancer)
  • Iceberg lettuce (full of water and has no nutritional value)
  • orange juice or orange peel, (this causes cancer in male rats, although it protects against mammary tumors in does.)
  • blue cheese dressing (toxic!)
  • licorice
  • rhubarb
  • red cabbage (causes gas)
  • artichokes (causes gas)
  • raw banana, potato skins, green or starchy potatoes (not ripe all the way)
  • poppy seeds can cause neurological damage and sometimes death
  • “junk foods” (chips, and fast food products and beware of buffet foods with preservatives in them)
  • excessive candy and/or chocolate. One chocolate chip, for instance, is fine and often acts as a bronchio-dialator  which helps rats with respiratory problems.

I hope this information will be of use to you in deciding what to feed your rat. Please remember to consult your veterinarian to determine the proper care of your pet.  This list is only intended as a general reference – it should not replace the advice of your veterinarian.

Food and Water

Good-quality food and fresh, clean water must be readily available at all times. Laboratory rodent chows (milled pellets or lab blocks) are preferred. These foods are available from feed stores, pet shops, and suppliers. The rodent diets containing seeds and nuts are not recommended because they contain too many fats and oils, provide inadequate protein levels, and are not necessarily balanced and can cause obesity in your rats.

Unfortunately like our own junk foods out there, owners see colorful boxes of food and supplements at the pet stores. Included among these feed may be seed mixtures, seeds mixed with vitamin and mineral pellets (often ignored by the pet), hay cubes, pellet food, complete diets, salt blocks, pieces of chewable wood, and a variety of treat foods that lure the unsuspecting buyer because those treats resemble the snack foods preferred by pet owners. Of most pet rodent feeds available, only the pellet, complete diets (with at least 16 percent quality protein) have use as primary diets.

Conventional (natural ingredient) pet animal diets produced by reputable companies usually contain adequate balanced nutritional components, but even those diets can be altered by damp, heat, oxidation, and vermin contamination. Owner-compounded diets, on the other hand, are more likely than are commercial products to lack certain trace nutrients, to be unbalanced, or to be contaminated with bacteria or mold. Pellet food involves heat, moisture, binder, hot-air dry, and compression in a shaped mold. This form usually is well received by rodents old enough to gnaw the hard pellets, and little is wasted. Powders and meals are wasted: the dust can collect around mouths and in noses and predispose a pet to medical problems.

Table scraps and alternative foods can be offered but these should be limited to healthful items like whole-wheat bread, non-fat yogurt, fresh fruits and vegetables, lean protein sources such as tuna, chicken, etc. and should not exceed 15% of what the pet consumes daily. If the above feeding recommendations are followed, malnutrition and related problems are very unlikely among pet rodents. Vitamins and salt blocks are generally unnecessary if you follow a good healthy diet.. Oil-rich and high-fat foods must be avoided.

Their dry food can be hung in a food dispenser or put in a heavy ceramic dish that won’t tip over. This prevents little opportunity for fecal (stool) and urine contamination of food. Fresh water is made available and kept free from contamination by providing it in water bottles. The tubes can become clogged with food debris, so they must be checked daily. The tube must be accessible to the smallest rodent within the enclosure. Before baby rats are fully weaned, they begin drinking water and eating pellet foods, so these essentials must be accessible to them at this time. Many deaths of baby rodents are due to starvation and dehydration. Like human babies they need feeding more often.

Food consumption varies with the quality of the food offered, the age, health and breeding status of the individual, the environmental temperature, and the time of day. Rats tend to eat more at night, but day time feeding is also common. Water is best provided in bottles with, preferably, metal sipper tubes. Large square types with wide necks can be hung on the cages and are very good at staying on and easy to clean.

Having fresh water available daily is critical, as many pet rodents presented as “sick” are in fact dehydrated.

*NB: Edited to a more correct description. Mr.R