Rats are curious and intelligent creatures, so they’re usually very good at working out which foods are good and which are bad for them. With a keen sense of smell and a discerning palette, rats will often make a beeline for the foods they like the most and avoid what they don’t. But what are the foods they really shouldn’t eat? Are any foods toxic?
This article will look at what foods you should never give to your rats and discuss the foods that aren’t toxic but aren’t good for them either!
What Can’t Rats Eat? Toxic & Unsafe Foods
Some foods are toxic to rats and should never be given to them or left out where they could get to them. Some foods aren’t great for rats or should be given with caution (which we’ll discuss later on).
The following list of foods are all harmful to rats, however, and shouldn’t be offered even in small amounts.
Fruit Pips, Seeds, and Stones
It’s not unknown that certain fruit seeds can contain a substance that’s converted into cyanide in the stomach. Amygdalin, a chemical found in apple pips, plum, peach, cherry stones, and other fruit seeds, is converted into hydrogen cyanide by enzymes in the stomach. Cyanide is, of course, a poison. The small amount found within a fruit pip is harmless to us, but rats are much more susceptible to it.
Ingesting several apple pips could cause poisoning in a rat if they ground and swallowed them. Other fruit pits can do the same, so it’s best to completely remove any seeds or pips from fruits before giving them to your rats.
The flesh of the fruit is completely safe; only the pips, seeds, and stones have this effect.
Raw beans and pulses, such as kidney beans, black beans, haricot beans, etc., are very dangerous to eat for both humans and rats.
These dried beans contain a chemical called lectin-phytohaemagglutinin, which causes damage to the digestive system and acute poisoning that can lead to gastrointestinal upset. These lectins can also cause red blood cells to agglutinate (clump together), so they should never be given to your rats.
Avocado Skin and Stones
While there is spotty evidence to suggest that avocado skin and stones can harm rats, there is plenty to show that the chemicals found in them have very negative effects on other animal species. Because of the lack of clear guidance regarding the skin and stones of avocado, it’s best to avoid giving it to your rats altogether.
Studies exist that show a powdered avocado stone did not affect rats when given, but symptoms such as GI upset, and even cardiovascular problems have been seen in other animals.
The flesh is fine to give, however, and has some great benefits, including healthy fats and vitamins.
Potatoes that have turned green are not safe for rats to eat.
The green skin and flesh contain a chemical called solanine, which is toxic to many animals, including rats.
Solanine toxicity can cause gastrointestinal symptoms such as diarrhea, neurological problems, and even death. Cooking doesn’t destroy solanine, so you shouldn’t ever give green-skinned potatoes to your rats.
Foods Containing D-Limonene
This portion really only applies to male rats, but it’s important to know.
Citrus fruits and their juices, mangos, and spices such as ginger all contain high levels of d-limonene. In large amounts, d-limonene affects the kidneys of male rats due to a protein only males produce. This protein can bind with d-limonene in the kidneys and cause lumps of protein to build up, potentially causing damage to the organ.
While small amounts of citrus aren’t likely to cause any issues for your male rats, it’s still best to avoid feeding it as there are many other, safer options out there.
What Foods Are Unhealthy? Foods to Be Careful With
Now we’ve discussed the foods you shouldn’t ever give to your rats; we can look at foods that they can have, just in small amounts or in certain situations. While too much of even a good thing can be bad, the following foods negatively affect your rat’s health.
Foods High in Fat
Obesity is a common problem among pet rats, and too much fat in your rat’s diet can mean big problems for their health. Even healthy fats eaten in excess provide excess calories, which in turn causes rapid growth, obesity, tumors, and even decreased longevity.
Rats need around 5% fat in their diet to be healthy. Any excess of fat is stored as fat deposits in the body. Fried food, animal fats, and treats can all provide far more dietary fat than your rat needs.
Foods High in Sugar
Sugary foods are another group that you should avoid giving to your rats regularly. Sugar is well documented to be harmful to your rat’s health, but their teeth are what are most obviously affected.
Excess sugar causes tooth decay and pain, including damaging the closed-rooted molars, which aren’t regrown. Chocolate, cake, simple carbs like white bread, and sweet treats are best only given on occasion as they’re full of sugar or easily metabolized into glucose in the body.
Certain sugars, such as fructose (fruit sugar), are healthier but shouldn’t be given in excess. Moderation is key!
Foods High in Salt
Avoid giving your rats large amounts of foods high in salt, such as salted nuts, salted crackers, ham, etc.
Just like in humans, consuming excess salt can cause long-term health issues like hypertension or heart issues in rats.
High Protein and Phosphorus Foods for Older Rats
Rats, like many animals, can experience a decline in kidney function as they age. This has been shown in studies to be something that gradually worsens until the final stage of the renal disease occurs at around 2.5 years old.
As owners, we want to do everything we can to delay or prevent this. Altering your aging rat’s diet can help to slow down damage to their kidneys by reducing the amount of protein and phosphorus they consume.
The exact reason why a reduced protein and phosphorus diet protects kidney function is unknown, but studies have proven this to be the case.
Trying to balance the protein and phosphorus amounts over your rat’s life will help to protect their kidney function. Choosing grains lower in phosphorus, like millet, sorghum, barley, and rice, can help to reduce the overall phosphors in the diet. Protein should be kept to a maximum of 12% for rats over 18 months of age.
Foods High in Oxalic Acid
Unlike some other species, rats generally don’t seem to suffer from kidney problems due to excessive oxalic acid in the body. But certain foods are high in oxalic acid, which could cause problems for rats with kidney problems. This is because oxalic acid binds to minerals to form oxalate crystals. However, most rats are absolutely fine to eat foods higher in oxalic acid in moderation!
Foods such as spinach, beets, nuts, and sweet potato are all high in oxalic acid, but they also provide health benefits to rats when fed in moderation.
Rats are generally good at distinguishing between what they should and shouldn’t eat, but some are more food-motivated than others and will eat whatever they can find!
As their owners, it’s our responsibility to keep them safe and provide them with a healthy (and delicious) diet.
By knowing the types of foods to completely avoid and the foods to give in moderation, you can give your mischief the nourishing diet they need while not skimping on enrichment.
- Role of Low Protein and Low Phosphorus Diet in the Progression of Chronic Kidney Disease in Uremic Rats
- High-protein Diets and Renal Status in Rats
- Nutrient Requirements of Laboratory Animals: Fourth Revised Edition, 1995.
- Alison Campbell – The Scuttling Gourmet Books
- RSPCA: What to Feed Rats