Rat Food and Tumors

soft focus of the rat was in a cage catching a rat. the rat has contagion the disease to humans such as Leptospirosis, Plague
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Rats are sensitive and short-lived rodents, but many people have had the opportunity to discover what intelligent and personable pets they make. These people also know how prone to tumors and other life-threatening diseases their little rodent friends are and probably don't want to do anything to harm them. Recent studies have found that the food we are feeding our pet rats may be causing some of the tumors we see.

Normal Rat Food

Rats typically eat hamster, gerbil, mouse, or rat food purchased in pet shops. These pre-packaged foods are seed-based and contain kibble, corn, and other grains. Sometimes dried fruits and vegetables are also included along with vitamins and minerals.

Rats should eat a combination of fresh fruits and vegetables and small amounts of good quality rat pellets or rat cubes. Cereals, grains, seeds, breads, biscuits, sweets, cooked pasta and rice and breakfast cereals should be considered treats and offered in very small amounts.

The Problem With What We Feed

Just like with people, GMO's may be harmful to pet rats. GMO stands for a genetically modified organism and studies have shown that these non-naturally occurring foods can be harmful when eaten. A French study recently tested out this theory on rats and proved that non-GMO corn is much safer for our pets (but there is a lot of debate on this topic still).

Genetically Modified Corn

The University of Caen in France discovered that genetically modified corn that is made to be resistant to spraying of weed killer such as Roundup causes mammary tumors, and severe kidney and liver damage when fed to rats. They ran a study where they fed this corn to rats and 50 percent of the males and 70 percent of the females died prematurely while only 30 percent of males and 20 percent of females in the control group died prematurely.

The company that makes the NK603 seed that was tested claims the researchers had reached "unsubstantiated conclusions" but was published in the Food and Chemical Toxicology journal nonetheless. Due to concerns and the safety of GMO foods, further research is being done by the European Food Safety Authority.

What To Feed

We have already heard about the potential effects of GMO's in humans and many people now avoid eating these foods altogether for health reasons (but there are two sides to this debate). But are there good options for rat owners who want to avoid feeding these kinds of foods to their pets? The short answer is no. There is no pre-packaged organic, seed-based rat diet available from your local pet shop.

Instead of buying prepackaged rat foods from the store you can offer your rat a variety of healthy foods. Organic options of vegetables, a small number of fruits, grains, seeds, and dehydrated foods that you would typically find in a rat food mixture can all be offered daily to your pet rat instead of just pouring GMO's from a baggie into your rat's bowl.

Health food stores often have bulk dehydrated peas, seeds, and other grains available for purchase. To this, you can add some fresh veggies and fruits and alfalfa hay from a local farmer if possible. This would be an ideal diet, potentially free of harmful GMO's and chemicals.

In addition to the actual foods, calcium, chromium, manganese, and Vitamin B12 need to be added to your homemade diet to provide the essential nutrients as decided by the National Research Council. An exact recipe of a well-rounded diet for pet rats can be found on The Rat Fan Club website.


You should make sure you avoid feeding chocolate, raw beans, raw sweet potato, cabbage, brussels sprouts, green potatoes, sweet or sugary treats, any other "junk food," caffeinated beverages, and carbonated drinks.

Article Sources
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  1. Séralini, Gilles-Eric et al. Republished Study: Long-Term Toxicity Of A Roundup Herbicide And A Roundup-Tolerantgenetically Modified MaizeEnvironmental Sciences Europe, vol 26, no. 1, 2014. Springer Science And Business Media LLC, doi:10.1186/s12302-014-0014-5