It’s a bit of a cliché, isn’t it, the cheese in the rat or mouse trap? Anyone who has ever watched Tom & Jerry is familiar with the image.
But do rats really like cheese? And is it safe for them to eat?
Some types of cheese are perfectly fine for rats to eat. However, cheese is high in calories and fats and often salt, too – so it should only be fed in very small amounts. Some types of cheese are a potential choking hazard for rats.
To find out what cheese is safe to share with your pet rats, keep on reading.
Can You Feed Your Pet Rat Cheese?
Is Cheese Safe for Rats?
Nutritionally speaking, cheese is a wonderful food. It boasts a good serving of proteins, healthy fats, and fat-soluble vitamins such as vitamin D, A and E1. Contrary to popular belief, rats as a species are not lactose intolerant, so the consumption of dairy will not usually cause diarrhea2.
Most cheese is fine for rats to eat. There are a few issues with it, though:
1.) Cheese is quite high in calories (and fat). Since obesity is a big problem in pet rats, high-calorie foods should be limited and only offered as an occasional treat. If your rats are already overweight, cheese is not the best food to offer them – stick with vegetables and fruit instead.
2.) There is often a lot of salt in cheese. Numerous rat studies have shown an increase in blood pressure after the consumption of sodium3. The research still isn’t completely clear on the role of salt consumption in the development of hypertension, but it’s safe to say that a diet low in sodium is healthier for your mischief.
3.) Some types of cheese have a sticky, soft texture that can make them hard for rats to chew. Rats have different teeth than we do, and they don’t have any molars to help them grind sticky foods. Soft cheeses are therefore a potential choking hazard for rats.
4.) Soft cheese can be contaminated with Listeria4, a bacterium that can infect rats5 – just like humans. To avoid this, cheese products made from pasteurized milk should be selected. However, it’s best to avoid soft cheeses altogether, as they can cause choking (see point 3).
What Kind of Cheese Can Rats Have?
So, what types of cheese can your rats eat, then? Hard cheeses are fine in moderation. Good choices are: Gouda, Emmental, Gruyere, Edam, and Cheddar cheese.
As hard cheeses are high in salt and calorie-dense, you should not feed them daily. Offer a small piece per rats once a week as a special treat.
Hard cheese also makes a great training reward when you are teaching your rat new skills, as it can be cut up into very small pieces.
Can Rats Eat Mozzarella Cheese?
As we’ve seen, soft cheeses such as mozzarella can potentially lead to choking in rats. Other types of cheese that are best avoided include brie, camembert, queso blanco, ricotta, gorgonzola, and blue cheese.
The often-cited issue that moldy cheeses are toxic for rats is not true – there is no evidence that moldy cheese contains any toxins that are harmful to rats. But since their texture is usually hard for rats to manage, they still make the list of cheeses you don’t want to feed your rats.
What Cheese do Rats Like Best?
Which cheese they like best depends on your rats, of course. Just like humans, individual rats have different tastes and preferences.
You can offer them a bit of whatever you are nibbling on – as long as it’s safe for them – and learn with time which rat prefers which type of cheese.
Cheesecake contains a lot of sugar and is therefore not suitable for rats. Sugar causes an addictive reaction in the rat brain that even exceeds the high of a cocaine rush6. Rats will quicky develop a preference for sweet foods and tend to consume them in excess.
Since pet rats are prone to obesity – and longevity in rats is in turn correlated with restricted feeding and plenty of exercise7 – any food that contains sugar should be off the menu for pet rats. Also, the texture of cheesecake can be hard for rats to manage.
Can Rats Eat Cheese Puffs?
Cheese puffs usually contain lots of salt and spices, sugar, and a ton of artificial ingredients. They are high in calories and not a good choice of snack for your rats.
What Can Rats Not Eat?
As we’ve covered, it’s best to avoid foods that contain a lot of sugar or salt – this applies to most processed foods. Caffeine and chocolate are also a “no” on the rat diet. Other toxic foods include fruit pits and stones.
Some foods should only be offered cooked, such as beans, potatoes, and sweet potatoes. Others are only unsafe for bucks to eat, such as mangoes and citrus fruits (mainly the skin, but the rest of the fruit is probably best avoided, too).
Whenever you’d like to offer your rats a new food, it’s best to take a couple of minutes to research any harmful effects it may have. Some foods are fine in moderation but can cause digestive issues when offered in abundance.
To Sum Up
The cliché is there for a reason – rats usually like cheese and will eat it if it’s offered. However, cheese should only be fed occasionally and in small amounts. Hard cheeses are best, as soft cheeses can be a choking hazard and may pose the risk of listeriosis.
1. U.S. Department of Agriculture. FoodData Central – Cheese, cheddar. 2019. https://fdc.nal.usda.gov/fdc-app.html#/food-details/328637/nutrients.
2. De Angelis RC, Giuli GG, Rogano RN, et al. Lactose load diet effect in rats. Arq Gastroenterol 1984;20:166-169. https://pubmed.ncbi.nlm.nih.gov/6743048/.
3. de Wardener HE. [Sodium and hypertension]. Arch Mal Coeur Vaiss 1996;89 Spec No 4:9-15. https://pubmed.ncbi.nlm.nih.gov/8952809/.
4. Centers for Disease Control and Prevention (CDC). Listeria – Prevention. 2019. https://www.cdc.gov/listeria/prevention.html.
5. Michelet C, Leib SL, Bentue-Ferrer D, et al. Comparative efficacies of antibiotics in a rat model of meningoencephalitis due to Listeria monocytogenes. Antimicrob Agents Chemother 1999;43:1651-1656. https://pubmed.ncbi.nlm.nih.gov/10390217/.
6. Lenoir M, Serre F, Cantin L, et al. Intense sweetness surpasses cocaine reward. PloS one 2007;2:e698-e698. https://pubmed.ncbi.nlm.nih.gov/17668074.
7. Drori D, Folman Y. Environmental effects on longevity in the male rat: exercise, mating, castration and restricted feeding. Exp Gerontol 1976;11:25-32. https://pubmed.ncbi.nlm.nih.gov/1278267/.
Nina has a degree from the Veterinary School in Zurich, with a special focus on microbiological research. Nina has a passion for sports, nutrition and the outdoors and she loves all pets, but rats have a special place in her heart. When she’s not working or reading and writing about all things related to pet health, she loves to travel and surf.
As a small animal veterinarian, Nina is your go-to expert on pet health and nutrition.