Is it OK for a house cat to eat a mouse?
Cat Health and Wellness

Can Cats Get Sick from Eating Mice?

Most cats are hardwired to enjoy hunting wild prey, but few domesticated house cats eat mice. Your cat is more likely to hunt for sport. This is why cats present dead mice to owners as a gift.

If a cat eats a mouse, it may become sick. Rodents often carry diseases, parasites, and viruses. These include toxoplasmosis and tularaemia. The mouse may also have consumed toxic rodenticide.

Even if a cat does not eat mice, hunting can still be a hazardous activity. Cats use their teeth to kill mice, which could pass on a bacterial infection. This is even likelier if the cat actively swallows and digests the prey.

Do All Cats Eat Mice?

Mice are small and offer a cat limited nourishment. A mouse will only provide 30 calories of a cat’s daily requirement of 240. That’s a lot of unnecessary hunting. Your cat knows that you will feed it. The cat will likely only eat a mouse if it is hungry or deficient in taurine.

In addition, some cats lack a killer instinct. Cats are taught how to hunt by their mother as kittens. A cat taught to hunt but not kill will lose interest after catching a mouse. The cat has had its fun.  

Will Eating Mice Make My Cat Sick?

Cats eating mice invariably comes with risk. Mice, and other rodents, are not clean animals. There is no way of knowing where the mouse has been. It could be carrying any number of diseases or parasites. These can be passed onto the cat after ingestion.

There is a minor risk of choking when a cat eats a mouse. The small bones of a mouse could be lodged in a cat’s throat. Ordinarily, the cat will grind these bones down. The risks to your cat are likelier to be medical in nature. The risks of eating to mice to cats include:

  • Toxoplasmosis
  • Tularaemia (rabbit fever)
  • Yersinia pestis
  • Leptospirosis
  • Hantavirus
  • Rickettsia infection
  • Intestinal or external parasites
  • Toxicity, if the mouse has consumed rodent poison

This does not mean that all cats that eat mice automatically become sick. If this was the case, there would be no feral or stray cat populations. But Behavioral and Neural Biology has stated that many domesticated cats prefer hunting birds to mice.

If you catch your cat with a mouse in its mouth, try to remove it. The sooner your separate the cat from mouse, the likelier your cat is to stay safe.

If your cat has eaten a mouse, or is acting strangely after being outside, you may need to identify behaviors related to sickness before seeing a vet.

will cats eat mice that have been poisoned?

1/ Toxoplasmosis

Toxoplasmosis is caused by the parasite toxoplasma gondii. This parasite lives in soil, which is how mice catch the disease. If a cat eats an infected mouse, toxoplasmosis will be passed on. The parasite lives in the cat’s intestines.

Toxoplasmosis is common in cats. As a result, many cats build a natural immunity to the disease. Young and old cats remain vulnerable, though. Left untreated, toxoplasmosis can lead to liver or lung failure. Other symptoms include diarrhea and muscular weakness.

Infected cats shed toxoplasmosis in the feces. Ensure you regularly clean the litter tray of your infected cat. Antibiotics will clear up toxoplasmosis.

2/ Tularemia

Tularemia is often associated with rabbits, hence the colloquial name of Rabbit Fever. The disease also lives in mice, though. This means that a cat can be infected with tularemia.

Tularemia is a dangerous condition that requires fast, aggressive treatment. It can be deadly if ignored. The most prominent symptom is a severe fever that affects a cat suddenly. Your cat’s body temperature will rise above 104 degrees Fahrenheit if living with tularemia. Other symptoms include:

  • Swelling and pain in the abdomen
  • Swollen lymph nodes
  • Jaundiced skin tone
  • Slow heart rate
  • Constant urination

If captured early enough, tularemia can be cured. Intravenous fluids will be used to flush the disease from your cat’s body. Antibiotics will then follow. Sadly, the mortality rate of tularemia is high. Vaccinate your cat against this disease for its own protection.

3/ Yersinia Pestis

Yersinia pestisis a mild strain of bubonic plague. It is sometimes referred to simply as the plague. Your cat does not have the Black Death. Yersinia pestis can be fatal in senior cats if untreated, though.

The condition is passed on through fleas that feed on mice. Fleas carry the bacterial disease, which invades the cat’s blood when the fleas bite. Once in the blood, the bacteria travel to the lymph nodes. From here, the disease mutates and impacts the lungs. Symptoms of yersinia pestis include:

  • Fever
  • Swollen lymph nodes
  • Lethargy
  • Loss of appetite
  • Ulcers in mouth and throat
  • Discharge from the eyes and mouth
  • Skin abscesses

The Journal of Medical Entomology describes continued fever as the most concerning symptom. In a study of 16 cats diagnosed with plague, 6 died. All of these cats experienced high body temperatures.

If you spot symptoms, take your cat to see a vet. Antibiotics were not available in the 17th Century. Prescription medication will usually clear up the problem with little fuss.

cat throwing up after eating mice

4/ Leptospirosis

Leptospirosis is a bacterial infection that damages a cat’s entire body. The bacteria in question are most commonly found in mouse urine.

Nature explains that mice use urine to communicate with each other. This is to warn other mice that a predator is in the vicinity. A cat will often consume urine if eating a mouse.

When the bacteria found in leptospirosis affect a cat, it burrows into the skin. The bacteria multiply and harm the cat’s eyes, liver, kidneys, and nervous system. Leptospirosis can also render a cat infertile. Symptoms of leptospirosis in cats include:

  • Sudden-onset fever
  • Dehydration
  • Muscle stiffness and reluctance to move
  • Blood in the vomit or feces
  • Coughing
  • Lethargy and depression
  • Chronic thirst
  • Inability to urinate
  • Loss of appetite
  • Swelling of the nose and throat

Leptospirosis is highly contiguous to cats. Handle an infected cat with care. Treatment will typically involve prescription antibiotics.

5/ Hantavirus

Hantavirus is a respiratory condition linked to mouse droppings. The Journal of the American Association confirms that cats can be susceptible to the condition, and not just humans.

Hantavirus is often symptomless in cats. If this is the case, it’s safe to assume that your cat is unaffected. Senior cats are likelier to struggle more with the condition than younger, healthier cats.

If it takes hold, feline hantavirus will present as a serious respiratory infection. The following symptoms are common:

  • Vomiting and diarrhea
  • Fatigue
  • Shortness of breath
  • Muscle stiffness
  • Unsteadiness on feet
  • Elevated body temperature

This issue must be treated with antibiotics. The condition will worsen with time, and will eventually render a cat unable to breathe.

is it OK for cats to eat mice?

6/ Rickettsia Infection

This disease originates with fleas and mites that feed upon mice. This disease belongs to the spotted fever family.

Most cats are not impacted by rickettsia infection. Even if the disease is passed on, the immunity system can often fight it. Senior cats have weaker immunity though. This could leave an older cat at risk.

If the cat is impacted by rickettsia infection, it will manifest in the blood and nervous system. Symptoms of this disease include:

  • Lethargy and muscle weakness
  • Loss of balance and uncoordinated gait
  • Heightened sensitivity to light and sound
  • Nausea
  • Slow blood clotting in wounds and injuries
  • Difficulty urinating
  • Bleeding from the eyes and mouth

Rickettsia infection is treated with antibiotics. If captured early, the prognosis is good. The disease is contagious, though. The cat should be quarantined until fully recovered.

7/ Parasites

Parasites are an ever-present risk when a cat eats a mouse. The dangers of fleas found in mice have been discussed already. Mice can also play host to ticks and intestinal parasites, though.

Ticks

Ticks feed on multiple species of animals over the course of their lifespan. Each of these animals may be carrying their own diseases.

The biggest concern surrounding ticks is Lyme disease. If you like in a rural area with a deer or elk population, this is a significant risk.

The tick does not need to attach itself to your cat to cause damage. The tick’s body could burst when the cat bites a mouse. This will potentially spill infected blood in a cat’s mouth.

Roundworms

Mice will carry the larvae of roundworm inside their bodies. When a cat eats a mouse, these larvae make their way into the cat’s intestines. From here, the larvae grow into adult roundworms.

Roundworms are a common ailment. Almost all cats will experience them at one time or another. This does not mean that the issue should be ignored. Roundworms can make a cat uncomfortable. Symptoms include:

  • Vomiting
  • Dull, unglossy coat
  • Unexplained weight loss

Roundworms are also visible in a cat’s feces. These will be long and white in appearance. Treat roundworms with a standard over-the-counter remedy.

my cat ate a mouse should i be worried?
Tapeworms

Tapeworms are parasites that live within your cat’s intestines. An adult tapeworm is typically around eight inches long. Tapeworms can break apart and infect other parts of a cat’s body. They will manifest as small, white rice-like specks in cat feces.

It’s rare for a tapeworm to be a medical emergency. Ordinarily, these parasites have no symptoms.

A heavy infestation can lead to sudden weight loss. This is because the tapeworms are consuming your cat’s food before it can be digested. This will affect the cat’s long-term health.

Tapeworms are treated with regular preventative medication. You won’t need a prescription. The pills/powder sold in pet stores will suffice.

8/ Toxicity

Cats eating mice can conclude a dangerous chain. If the mouse previously swallowed rodenticide, the cat will consume this toxin by proxy.

A one-off occurrence is unlikely to be fatal. Cats are obviously much larger than mice and tolerate the poison better. Even small amounts of rodenticide can leave a cat sick, though.

Rodenticide acts as an anticoagulant. It floods a mouse’s body with calcium, thinning the blood until it stops clotting. Eventually, this causes death in the mouse. Excess calcium is just as dangerous in cats. If a cat consumes enough rodenticide, kidney failure can follow. Symptoms include:

  • Lethargy
  • Vomiting and diarrhea
  • Panting and trouble breathing
  • Drooling or frothing at the mouth
  • Muscular twitches, potentially leading to seizures

If you have a cat, do not use rodenticide in or around the house. Your cat may consume the poison directly, which is far more dangerous. At the first sign of toxicity in your cat, seek veterinary assistance. The damage to a cat’s vital organs can be irreversible if left untreated.

Many cats eat mice without significant health concerns. Cats have evolved over thousands of years to dine on these rodents, after all. If you are concerned, prevent your cat from hunting wild prey. Playtime with or without toys can be just as exciting for an indoor cat.