Authors: Karen Grant RN,
Amy Epperley of Phoenix Gate Rattery, and
Brandi Saxton, author/publisher It’s a Rat’s World magazine

As we have gained more knowledge/information regarding rat nutrition, Rat Guide has revised this Diet Page to reflect more current information.

Good nutrition is the basis for maintaining overall good health in your rat. Implementing a well-balanced base diet that incorporates all the minimum daily requirements of essential nutrients, vitamins, and minerals, along with a variety of fruits, nuts, and vegetables goes a long way in meeting the needs of the rat. It affects both their life span and appearance and can even play a hand in their general temperament. With so many commercial and homemade diets out there, however, it is hard to immediately know what is best for them.

As science and technology become more advanced, so too does our understanding of diet and nutrition. This guide is aimed to help rat owners, from old to new, make informative decisions on which diets are best for their rats.

Introduction to Balanced Nutrition

The first step to understanding, formulating, and implementing the right diet is to understand how the rat’s metabolic system works and what their needed daily nutrient requirements are. Both wild and domesticated pet rats are omnivores, meaning they eat plant and animal matter. As owners we can give our rats a diet that contains both or stick to a strictly plant one, by providing a staple diet, along with fresh whole foods for added benefit and variety. When offering fresh foods, owners do need to keep in mind that, like humans, rats will often prefer some foods over others. Typically, these are foods known for a desirable taste but are not necessarily nutritionally good. We will discuss fresh foods below.

The daily nutrient requirements of the rat are very similar to that of a human – with a few exceptions of rats needing 130% of calcium, 130% of manganese, 490% of vitamin K, and 290% of vitamin B12 more than we do. Depending on the life cycle stage of a rat, they may need increased or reduced percentages of essential nutrients, vitamins/minerals.

These stages of “special” diets are for rats in:

  • The reproductive cycles: actively breeding, pregnant or nursing
  • In the early development cycle: about 3 weeks to 5 months old
  • In the later years cycle: about 1.5 years – death

A listing of the estimated Nutrient Requirements for Maintenance, Growth, and Reproduction of Rats can be found HERE.

Staple Diet

Generally, the “staple” is a complete rat diet that is formulated by nutritionists specifically for rats and is usually found in only commercial products. Veterinary nutritional experts recommend that the staple portion should be at least 80% of the overall diet. The remaining 20% is made up by including fresh fruits and vegetables, and nuts. See Figure 2: Daily Menu for menu example.

The staple diet can be provided either through a high-grade lab block or a high-grade, nutritionally complete rodent nugget diet that is heavily fortified and formulated for the specific needs of rats in all or at various life cycles.

Ultimately, commercially purchased block or nugget diets that meet all the nutrition requirements for a rat can be fed as a single diet. This cannot necessarily be said for homemade diets, however. Until further scientific or nutrition studies can be done for each of the known homemade diets online they should not be used as a staple diet, but rather a supplemental one. More on this later.

Lab Blocks, Rodent Pellet/Kibble, and Nuggets

Lab blocks (food specially formulated for laboratory rodents) have become the most widely accepted staple diet for rats, both in the lab, and in our homes. Many commercial manufactures and mills picked up on this and started making their own version of blocks. Since not all blocks are created equally this can make it difficult to know which ones are best. Some of these same companies are also coming out with a similar rodent pellet/kibble to keep up with the market for a complete, fortified, commercially available rodent food. For this reason, we have chosen some of the more well-known commercial brands of rat food to discuss in detail.

The general rule of thumb to determine a diet’s suitability is by its protein % and its main ingredients. The percentage of protein in the rat diet should be kept at 11% – 18% for a normal, healthy adult rat, not actively in a reproductive cycle or later years cycle. For those in an active breeding cycle or in the early development years cycle the percentage should be a minimum of 18% to about 22%. One of the first ingredients should be either soy or wheat, not corn, which is a fatty filler. Although this topic can be controversial there are some indications that a female rat fed a diet high in soy may be less prone to mammary tumors and decreased pain perception. However, this soy is not as beneficial for males it seems, and a staple diet of a 11 – 14% protein block is best for older males. For more information, see references at the end of the article.

Currently there are only a handful of recommended commercial diets on the market that are actually suitable for pet rats. It will require an owner’s due diligence to seek them out and avoid the others. Many of the acceptable diets can either be found in pet stores or purchased online in bulk, and some can only be purchased through designated distribution dealers. The serving size per rat, per day, will vary based on manufacturer packaging instructions. The serving size per day should be divided into two separate meals and given twice a day. Be sure to read and follow instructions accordingly to ensure your rat is not being under or overfed. Pay attention when giving them each of their daily portions and remove any spoiled or stale foods from previous feeding. Serving sizes can be adjusted as needed.

Here is a review of currently available blocks, pellets/kibble, and nuggets:

Envigo – Teklad Global (formally known as Harlan Teklad): One of the better brands and currently one of the most widely used of block food is the Envigo blocks, which can be purchased in bulk from the manufacturer: at This block can be harder to get, but there are now some online sites and rat organizations that sell and ship smaller quantities. Harlan also sells their trademark formula diets commercially to the public under the name Native Earth.

Envigo – Teklad Global makes the following rodent diets:

2014 Teklad Global 14% Protein- 2014 is a fixed formula diet containing a minimum of 14% protein and 4% fat. It is designed to promote longevity and normal body weight in rodents. It does not contain alfalfa or soybean meal.

2016 Teklad Global 16% Protein- 2016 is a fixed formula diet containing a minimum of 16% protein and 4% fat. It is designed to support growth and maintenance and does not contain alfalfa or soybean meal.

2018 Teklad Global 18% Protein- 2018 is a fixed formula diet containing a minimum of 18% protein and 6.2% fat. It is designed to support gestation, lactation, and growth of rodents. It does not contain alfalfa but does contain soybean meal.

Native Earth 18% Protein 4018 (40lb bag)- 4018 is a fixed formula diet containing 18% protein and 5% fat. Top ingredients are ground wheat, ground corn, wheat middlings, soybean meal, corn gluten meal, and soybean oil.

Mazuri® As a suitable alternative to Envigo, Purina Mills produces Mazuri®, which can also be purchased in bulk at the Mazuri® website: One advantage to this brand is that Mazuri® tends to be more commercially available than Envigo. A downside, however, is that it contains a higher percentage of protein and fat.

Purina Mills makes the following rodent diets:

Mazuri® Rat & Mouse Diet- This has a hefty 23% protein level and a crude fat level of 6.5%. The first five ingredients listed are dehulled soybean meal, ground corn, wheat middlings, ground wheat, and soybean oil.

Mazuri® Rodent Breeder formulas (6F, 9F)- This contains crude protein of 16%, crude fat of 9%, and crude fiber of 6%. The first five ingredient are ground corn, dehulled soybean meal, ground oats, porcine animal fat preserved with BHA, and cane molasses.

Oxbow- Available through online pet food sellers and occasionally in pet stores. This is an apple flavored pellet/kibble designed as a low-fat, low-protein diet with no corn.

Oxbow Essentials Adult Rat Food (3-lb bag/40-lb box)- Crude protein 15.0% (min), crude fat 4.0% (min), crude fiber 5.0% (max), calcium 1.50% (max). Main ingredients are whole brown rice, oat groats, wheat bran, wheat, soybean meal, menhaden fish meal, and soybean hulls.

Lafeber- Originally known for their Nutri-Berries for birds, they now make a formula that is a complete diet specifically for adult rats. Lafeber uses human-grade and non-GMO ingredients and according to their website, the “grains are shelled and then coated with stabilized vitamins, chelated minerals, and amino acids.” These nuggets, which encourage forging activity and provide mental stimulation, were formulated by trusted top exotic vets and nutritionist. Their rat food can be bought on their website: and some online retailers like Amazon or Chewy. Or check their website for local retailers.

Rascally Rat Nutri-Berries (2.5lb or 10oz bag)- Crude protein 11% (min), crude fat 3.8% (min), crude fiber 9% (max). Their main ingredients are ground oats, wheat flour, ground sorghum, soybean meal, millet hulls, dried bananas, dried cranberries, dried peas, and additional vitamins.

For a more in-depth article on Lafeber’s Rascally Rat Nutri-Berries see Figure 1: Lafeber

Facts on Commercial Formulas

Unfortunately, there are plenty of commercial brands that market their products for rats but are in fact not actually suitable as a complete diet. Well known and established brands also change their formulas from time to time. For this reason, owners need to carefully scrutinize any and all diets claiming to be a “complete diet” before feeding it to their rats. Formulas you should avoid are ones that include mostly corn, very high percentages of protein and fat, foreign and non-digestible ingredients, and are not stored and produced in a clean, moisture-free, insect-free location.

Seed Mixes- Generally, commercial seed and grain mixes are not recommended, as these mixes contain too much corn, seed, or filler ingredients. These mixes are not nutritionally complete either since rats tend to pick out the higher fatty contents that taste better and waste the rest. There have also been reports of these mixes containing trace amounts of a pesticide called ethoxyquin (which is known to cause cancer in humans) as a preservative. The dried corn in these mixes can also contain high levels of fungal contaminates, nitrates, and amines. These have been shown to cause liver cancer in rats and form nitrosamines, which are carcinogenic in the stomach.

Not All Rodents Are Alike- Many formulas are marketed as a complete diet for multiple types of rodents. Rats do not necessarily have the same nutritional needs as other pocket pets, so avoid using anything as a staple diet that claims it is also for hamsters, gerbils, guinea pigs, squirrels, or chinchillas.

Alfalfa- Although alfalfa meal is a frequently used ingredient in commercial pet rat food, its inclusion is neither harmful nor overly beneficial in moderate amounts. According to Thomas M. Donnelly, DVM, when alfalfa is added to a block food, it is used as a filler in the form of alfalfa meal or alfalfa protein concentrate to provide carbohydrates, fiber, and protein. But it only makes up about 4% of the total diet. This percentage may vary in other types of rat diets and seed mixes, however.

While it has not been shown that rats require a dietary fiber as part of a healthy diet, there is no reason to avoid a commercial rat diet just because it contains a small percent of alfalfa meal or alfalfa protein concentrate.2,21

Homemade Diets

Grain mixes, also called dry mixes, are a type of homemade diet or supplement diet that centers around using bulk grain ingredients found at local supermarkets or health food stores. Many owners are drawn to these because they offer a variety of ingredients to their pets. This can be a downside, however, since rats are known to focus only on the ones the ingredients they like and ignore those they are less of fond of. This means they are potentially missing out on a lot of essential vitamins and minerals.

There are other cautions to be noted with homemade diets as well:

  • Without a full scientific analysis of each of the currently developed recipes found online, or one you formulate yourself; it is impossible to ensure that any of these homemade diets meet all the nutritional requirements of a staple diet.
  • Some homemade diets use dog or cat food, which contain incorrect levels of fat and protein for a rat.
  • Many of the homemade diets can be too high in carbohydrates, calories, and sugars.
  • They do not specify for which life stage of the rat they were formulated.
  • They do not seem to provide any suggested serving sizes or feeding instructions.

Not all of the homemade diet recipes are inherently bad, however, and there are reasons many people chose them:

  • They provide variety, which many owners find valuable.
  • They might also be more affordable for an owner than a commercially developed diet.
  • They give owners more control over the ingredients their rats are eating, such as organic and GMO-free options.

Considering that none of the homemade diets are guaranteed to meet all the nutritional needs of a rat throughout their different life stages, it is recommended that they only be used when supported with the addition of lab block or one of the other staple diets listed above. If the homemade diet you chose suggests including dog food or lab block as an ingredient, make sure you are not using both, as this will give your rats far too much protein.

If you do choose to use one of these diets as a staple diet regardless, it would be wise to closely observe any changes to your rat’s health. This means paying attention to changes in their body conditions and activity level. Keeping a weekly weight chart on each rat would help determine if they are staying in a healthy range. Also keep an eye on how much of the ingredients your rat is actually consuming. If they are picky and skipping over a large portion of the mix, it would be best to avoid that diet and find one that is more palatable to your rat.

Since the homemade diets found online lack serving sizes, it is also crucial to practice portion control. Many owners tend to keep their rats’ dishes filled, but this leads to unhealthy amounts of food. If one of these diets is going to be used as a staple diet, an estimated serving size, per non-pregnant/lactating adult rat, per day, should be kept at around 1/4 – 1/3 cup. This can be split in two, with one portion given in the morning and the other at night. If your rat is pregnant, lactating, or very young and still in growth stage, see “For Pregnant and Lactating Females” in the “Other Feeding Considerations” section.

Whether an owner chooses to use a homemade diet as the staple diet or a supplemental one, make sure to check the rat’s dishes and cage for leftovers or stashed items before offering them more. Otherwise, this could lead to overeating.

The two most well-known, pre-formulated homemade diets online are:

Debbie’s Homemade Rat Diet– Created by Debbie Ducommun of the Rat Fan Club. This diet is comprised of fresh foods and has been revised throughout the years. It was last revised and updated on 5/12/16. When fed along with a staple diet, make sure to lessen the serving size amounts listed on the website.

Suebee’s Rat Diet– A very popular and well-known homemade diet. This can be used as a supplement with a staple diet already in place like Envigo lab blocks, Regal Rat by Oxbow, and Lafeber’s Rascally Rat Nutri-Berries. Suebee’s does not include serving sizes.

RMCA offers an additional listing of homemade diets contributed by other owners and breeders.

No matter which homemade diet you choose, you will want to store it in an airtight container in a cool, dry place.

Grains, Proteins, and Additional Ingredients Found in Homemade Diets

When shopping for the different ingredients in a homemade diet, or ones you provide as snacks, keep in mind that not all brands are equal. It is important to check the ingredients listed and avoid items with sugar or corn syrup listed as the first few ingredients.

Brands like Natures Path, Arrowhead, and Quaker for instance, only use rice or wheat for their puffed cereals, making them an optimal choice.

Notes on common ingredients found in homemade diets:

  • Oats- Should be dry rolled, not instant, and non-flavored. Do not overfeed, as this is a binding food and can cause constipation.
  • Puffed wheat cereal- Should be plain, unflavored, and contain no sugar. Inexpensive and well liked.
  • Puffed rice cereal- Should be plain, unflavored, and contain no sugar. Inexpensive and well liked.
  • Total Cereal- Great source of vitamins and minerals. Rats can be picky about eating it.
  • Soy Nuts- Unsalted and roasted only. Great source of protein and Vitamin K and helps ward off cancer.
  • Dried Fruits* Things like dried bananas, mango, cranberries, raisins, apple, and pineapple. Dried bananas should be just dried with no sugar added and not fried. Just Bananas brand is a good option.

*Remember that fresh fruit and veggies should make up 20% of a rat’s daily diet. Dried fruit can be offered, but should apart of the 20%, not an addition to. See more info in Fruits and Vegetables.

  • Dry Pasta- Provides carbohydrates. Should be fed in moderation. Consider healthy alternative pastas like tri-colored flavored pastas and wheat pastas.
  • Seeds- Sunflower and pumpkin/pepita seeds can be offered raw or unsalted and roasted. Give in moderation due to being high in fat and protein.
  • Nuts- Chock-full of healthy fats, protein, fiber, vitamins and minerals, most nuts are found to be safe for rats to eat either raw or roasted. They should always be given unsalted, however.

Some nuts contain lectin and phytates, which are anti-nutrients that can block the absorption of nutrients. But different factors such as, the varying quantities of anti-nutrients in the different nuts, along with how or if they were cooked, and the individual metabolism of each rat makes it hard to determine exactly how much absorption is being blocked. So, just to air on the side of caution, and because they also contain high amounts of fat, nuts should only be fed on occasion and in a tiny amount. Limit it to only one or two pieces per rat, depending on the size of the nut.

  • Peanuts Despite their name, peanuts are technically legumes (like beans) and should only be offered roasted and unsalted. Raw peanuts can be contaminated with mycotoxins, which are toxins naturally produced in mold (Aspergillus flavus) and can pose health risks to rats and humans. Like nuts, peanuts are high in fat and also contain lectin and phytates, so they too should only be fed occasionally. Limit it to only one or two per rat.
  • Muesli- Good alternative to the rolled oats. Offers variety but use sparingly due to sugar content.

These ingredients can be offered as snacks even if you are not using a homemade diet. But they should be given in varying portions only a few times a week. See Figure 2: Daily Menu for portion sizes. As with the staple diet, remove any spoiled or stale foods from previous feeding.

Fruits and Vegetables

Besides the staple diet, the remaining 20% of the daily requirements should come in the form of fresh, healthy fruits and vegetables. Not only does this provide additional nutritional benefits, but it also gives your rat variety in their meal. Rats are a lot like humans and find enrichment in variety.

Fruits and vegetable should be washed and provided as fresh as possible and can be given raw (unless otherwise noted*) or cooked in low-fat cooking options such as, steamed, boiled, baked, or roasted. Remove any perishable foods from the cage within 6 hours.

*A suggested daily menu and portion sizes of fresh fruits and vegetables, to be fed along with a nutritionally complete staple diet, can be found in Figure 2: Daily Menu. Also included is a list of foods to feed in moderation, foods never to feed, and how certain foods should be prepared.

On the subject of fruit, there has been some discussion regarding oranges causing cancer in male rats. It is the consuming of very large quantities of d-limonene, a naturally occurring oil found in citrus peels such as in orange rind, over a long period of time that they are referring to. The actual meat of the orange is not a problem and can be given to both female and male rats. 7,14,15

Snacks and Treats

Rats can eat most anything humans can, which is why many owners enjoy sharing their meal or table scraps with their rats. While they can eat most of the same foods, this needs to be done with consideration and moderation. The feeding of oversized treats, including healthy foods, seems to be the biggest contributor to obesity and health issues in pet rats. For this reason, it is imperative to not let your rats overindulge in snacks beyond their complete diet and limit their treat intake to approximately a bite-size amount.

Unhealthy Foods

Use common sense when deciding which foods to offer your rat. If something is unhealthy for humans, it is definitely unhealthy for rats. This includes carbonated beverages, fried foods, greasy or oily foods, and foods high in fat, sugar, calories, and sodium.

Healthy Foods

Any of the ingredients found in the homemade diets available online can be used for healthy snack options.

If you would like, you can also add in a daily protein like a bite of cooked, unseasoned liver, cooked lean meats, or cooked eggs as a treat. But if you have chosen to keep your rats on a vegetarian or vegan diet, you could offer soy yogurt, cooked tofu, cooked lentils, or cooked beans.

For some extra healthy options see Figure 2: Daily Menu

Other Feeding Considerations

Depending on where the rat is in its life cycle, you may want to provide a specialized diet to support their changing needs.

For Pregnant and Lactating Females- Because pregnant and lactating females are supporting additional lives, these mothers require additional nutrients during this life cycle. First, they should be fed only a high-quality staple diet. But you can also add in a homemade grain mix due to their higher caloric needs. Then, extra protein and fat should be added to their diet.

When you are feeding a staple diet, it should not contain less than 18% protein. Additional protein would be beneficial and can be provided by giving, soy milk, cooked tofu, cooked meats (chicken, beef, and fish), and cooked eggs (can be cooked with butter to add fat). Oatmeal mixed with whole milk, goat milk, or soy milk is also an option. Pregnant and lactating rats, and babies 3 – 7 weeks old should have their food amounts adjusted to meet the individual rat’s needs. They can eat up to twice as much as a typical-sized adult rat.

Pregnant and lactating females should also have plenty of clean water available to them at all times.

Once the female is done nursing, make sure to switch her back to her pre-pregnancy diet.

Older Rats- As a rat ages, their metabolism slows, and they may start to eat less and less. Especially if they are ill. If you find that your rat’s appetite has diminished, or their taste preferences have suddenly changed (which is not uncommon), it’s important to modify their diet to fit their activity and health level, along with their overall body condition.

If your rat can no longer hold their food easily due to hind leg paralysis or they need help through handfeeding due to illness, start providing pureed or soft foods.

Soft food or supplement options:

  • Baby food
  • Pureed fruits and vegetables
  • Staple diets that have been soaked in soy milk, water, or coconut water until soft
  • Avocados or eggs (great for extra calories and fat)
  • Oatmeal* or cream of wheat prepared with Ensure®, water, or baby formula
  • Quick breads (like banana and zucchini) and whole grain bread (great for extra calories and starch)
  • Soaked Granola
  • Cereals with dried fruit and nuts
  • Crackers
  • Nutri-Cal (a high calorie paste that can be purchased at pet stores or online to provide instant calories)

For additional calories, you can use Ensure® or baby formula. Some rats even prefer them with a wheat or rice baby cereal mixed into them.

Sick and elderly rats also tend to become picky about how they are fed. Do not assume lack of eating means they are not hungry. Instead, you may need to continually change the way you offer them food to get them to eat. If they will not take food from a spoon, try putting it on your finger instead. Or dispense liquid foods through a syringe. Take things slowly, though when using a syringe, to ensure your rat does not aspirate.

*Note: Flavored or instant oatmeal can be used in situations where an elderly or ill rat’s appetite needs to be enticed.

Low Sodium Diet- Pay attention to diet if your rat has certain health issues like heart or kidney disease. You can use low sodium lab blocks or Lafeber’s Rascally Rat Nutri-Berries and stick to adding only fresh fruits and vegetables. If you chose to use frozen fruits or vegetables, check the salt content first. Cut out all salty, baked, and processed foods, as well as any dairy products. Use filtered or bottled water instead tap.

Foods That Are Choking Hazards- Choking can and does occur in rats on occasion, whether young, aged, or ill. Reasons can range from heritable, genetic, and idiopathic related changes to the musculature of the esophagus (flaccidity, atrophy) such as, megaesophagus (a rare occurrence). Morphometric (change in shape and dimension) and biomechanical (movement) changes to the esophagus, and an inability of the tongue to sufficiently propel food bolus, can also result in choking, particularly in the aged rat. 22,23,24,27,28,34,35,36

While choking does not happen often, it is enough that precautions should be taken with certain types of food or avoided altogether. The following is a sample list:

  • Peanut butter*
  • Mashed potatoes*
  • Dried fruit
  • Popcorn
  • Chips
  • Honey*
  • Pizza crust
  • Doughy Bread

*Foods like peanut butter, mashed potatoes, and honey, to name a few, are safe as an ingredient, but when given straight, can pose a choking hazard. If something seems too thick, thin it out first.

Food Storage

Most commercial feeds have a shelf life of six months. But the longer the feed is stored, and if it is stored in a hot, damp environment, nutrients within the feed will be lost. Milling dates should be identified on bags and containers to ensure freshness. Store your rat’s food in a cool, dry area off the ground if possible, and away from strong-smelling products and disinfectants. Blocks can also be frozen in airtight Ziploc-type bags for a longer shelf life. Envigo lab blocks have a shelf life of six to eight months if kept in the freezer.

Note: Commercial foods are most often stored in warehouses before they are sold, which can expose them to parasites. For this reason, we suggest freezing any commercial rat food for 24 – 48 hours before feeding it to your rats, which will kill off any potential parasites.

Water, Bottles, and Dishes

Water- Rats need fresh filtered (not tap) water available at all times. Sipper bottles will keep their water much cleaner than having it in a bowl that can be stepped in, moved around, or dumped.

Water bottles are available in varied sizes and materials. Look for ones that are made of a durable plastic or glass, rather than softer plastic ones, as the former ones are easier to keep clean. A 6 – 8 oz. bottle is a good size for one to three rats, whereas a 12 – 16 oz. bottle works well for larger groups.

Many of the bottles available have different ways of attaching to the outside of the cage. Check which brands fit your cage style. If your rat is a chewer, you might want to invest in a guard that goes between the bottle and cage to prevent them from chewing holes in the bottles.

It is important to check the water bottle for leaks and to change to a clean bottle with fresh water daily. You can either clean the bottle with a long bottle brush every day or have extra backup bottles at your disposal. Beware that occasionally, the small ball in the sipper portion, may get stuck and not let water through when the rat licks at it. And sometimes the rubber seal can malfunction and cause the bottle to leak. Hanging two water bottles, per cage, can head off problems in the event one of them malfunctions.

Do not place the water bottle over the food dish. They tend to drip and can lead to soggy, spoiled food.

Dishes- Providing your rat with two food dishes will help to keep dry and moist foods separate. It is a good idea to use dishes of heavy stoneware or one of thick plastic that can attach to the side of the cage. This will prevent your rat from destroying the dish or dumping the food all over the floor.

In summary, healthy nutrition and an adequate supply of fresh food and water on a daily basis is essential to a rat’s overall health and safety. Not providing an adequate diet that keeps your rat slim and trim or providing water on a daily basis, can result in starvation (as seen in the Figure example below), illnesses, or even death.

Note: Because rats are neophobic, it is essential to check the cage and make sure yours are eating. If they aren’t, you may need to switch their diet to one they find more palatable.
Figure 3: Starvation, with a link to an article on the RMCA regarding starvation and abandonment.

Interesting Facts

  • Rats do not need a salt or mineral lick, as they are already provided in their complete diet. Salt licks are only needed by strict herbivores.
  • A rat’s body generates all the vitamin C they need – only Guinea pigs and primates must get their vitamin C from a food source or supplement.
  • Rats are not physically capable of vomiting due to a powerful gastroesophageal barrier (limiting ridge) and lack of the coordinated musculature for reflexive action, which is required to vomit. However, they are able to regurgitate, which is a passive action.13,16,17,18,19,25 Since rats do not vomit it is important to mention that for most surgical procedures, veterinarians do not require that you withhold food or water prior to surgery. More importantly, providing food and water up to the time of pre-op prepping (just prior to anesthesia being given) helps in preventing the rat from becoming dehydrated, or suffering ketoacidosis/hypoglycemia during surgery and recovery.

*Note: An exception to this may be when surgery involves the gut or abdomen. And even then, withholding food or water should be of short duration.

  • Not being able to vomit means they are not able to burp either. Which means giving your rat carbonated beverages could potentially cause them discomfort (besides being unhealthy). Even though gassy foods do not necessarily cause burping, and although rats do pass flatus, these types of food can also cause your rat potential discomfort. For this reason, drinks that are carbonated or foods that could cause gas (in excess) should be avoided.

List of Figures in above article are added here for convenience of reader:

  • Figure 1: Lafeber, for a more in-depth article on Lafeber’s Rascally Rat Nutri-Berries.
  • Figure 2: Daily Menu, for menu examples.
  • Figure 3: Starvation, with a link to an article on the RMCA regarding starvation and abandonment.


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Disclaimer:The above information is gathered from rat nutrition-based sources. Each owner is encouraged and advised to make educated choices about what is in the best interest for their rats and to make their own assessment of the information herein as with any source. The purpose of this article is for educational purposes within the home only and not to be publicly distributed in any way.


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