Bumblefoot in Rats

Causes, Treatment, and Prevention

Rat laying down curled up

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There are plenty of great reasons to keep your pet rats at a healthy weight and provide comfortable living conditions for them, but preventing medical problems like bumblefoot is an especially important role for caregivers. This disease can develop when rats and other small pets are overweight, living in wire-floor cages, exposed to infected rats, or when owners do not clean urine and bodily waste from the rat enclosure regularly.

While bumblefoot is easy to prevent, it can cause uncomfortable symptoms like ulcers on the feet and even be potentially fatal to rats when left untreated. The bacteria that causes this disease is contagious to other rats. Thankfully, it is not contagious to humans, and owners can typically keep their pet rats safe from bumblefoot with a few preventative steps.

What Is Bumblefoot?

Bumblefoot (ulcerative pododermatitis) is a painful bacterial infection in pet rats that causes ulcers to develop on the bottoms of the animal's feet. This condition usually develops when a wound on the animal's body becomes infected with Staphylococcus aureus or E. coli, often due to unsanitary conditions in the animal's enclosure. Small cuts or scrapes on the rat's feet allow the bacteria to enter the body. The infection leads to chronic inflammation and abscesses, and the name "bumblefoot" refers to the red lesions or "bumbles" that develop on the feet and cause the animal to limp.

Bumblefoot often occurs in rats that are obese or those that have a genetic predisposition to the ailment. Rabbits, birds, and other rodents are also susceptible to bumblefoot, but in rabbits, it's more commonly referred to as "sore hocks." Bumblefoot is also a major problem in chickens kept in captivity, particularly those kept in large numbers in small enclosures.

Symptoms of Bumblefoot in Rats

Owners may not notice the early signs of bumblefoot in their pet rats, but once the infection progresses, the following can be observed:


  • Lesions or "bumbles" on the feet
  • Limping
  • Excessively licking the feet
  • Reluctancy to walk or climb

Bumblefoot starts out as small reddened bumps that look a bit like calluses. Since the lesions first appear on the soles of the animal's feet, owners may not notice the symptoms of infection at this stage. However, these bumps can eventually become quite large. You may notice bloody footprints left behind by your pet rat. This sign occurs once the lesions have begun to bleed and scab over. Rats will become uncomfortable as pain increases, and owners will likely notice behavioral changes. If your rat is limping, licking its feet excessively, or acting reluctant to walk or climb normally, it's time to visit your small pet veterinarian.

Causes of Bumblefoot

There's a fair amount of disagreement about what cages or conditions may contribute to bumblefoot. However, it is generally believed that wire-floor cages, unsanitary living conditions, and health factors like obesity can make rats more prone to developing this disease. Whatever the specific cause, bumblefoot is almost exclusively a disease of animals kept in captivity, so keeping enclosures clean and free of irritants is crucial. The following causes can occur:

  • Unsanitary living conditions: Rats that are regularly exposed to feces, urine, and other unsanitary materials in their enclosures may develop bumblefoot from walking on them. Since the infection develops once bacteria enter small scrapes or cuts on the feet, poor sanitation is a risk factor that makes rats more likely to develop bumblefoot.
  • Bedding materials: Trauma from irregular cage surfaces or roughly textured bedding materials may play a role in the development of bumblefoot.
  • Infection from other rodents: Rats may pass bumblefoot to each other, especially if they're kept in the same enclosure. Since this disease is contagious, owners should immediately quarantine any rats that develop this infection and thoroughly clean all pet enclosures.
  • Obesity: Obese animals, rats included, appear to be more likely to develop bumblefoot. This may be due to uneven weight distribution or excessive pressure on the feet and legs when the animal walks. This is especially true in older rats, who naturally walk slower than others.
  • Wire-floor cages: The use of wire-floor cages, including wire shelves or balconies, has been suggested as a possible cause of bumblefoot. Wire cage floors should be avoided, but many decent rat cages have upper levels made from wire mesh. However, even rats kept on solid flooring can get bumblefoot, with one theory suggesting that exposure to urine pooled on solid floors (especially plastic) may contribute to the problem.

Diagnosing Bumblefoot in Rats

Once you've noticed symptoms of bumblefoot in your pet rat, a visit to your veterinarian is necessary. Your vet will do a physical examination on the animal, taking care to focus on its feet, and determine whether bumblefoot may be the cause. If this disease is suspected, samples will be taken to be tested in a laboratory. Your veterinarian will conduct culture and sensitivity tests on your pet to determine which bacteria caused the infection. This allows them to confirm the diagnosis and choose an antibiotic that will be most effective in treating your rat's case of bumblefoot.


A combination of oral antibiotics along with topical cleaning and treatment of your rat's wounds (as directed by your vet) is usually the first course of treatment for bumblefoot. When lesions do not respond to this treatment, your vet may recommend surgery. However, this has significant risks and limited success.

For bumblefoot lesions that do not respond to this basic treatment, surgical treatment may be necessary, but this has significant risks and limited success. Most importantly, owners should seek professional help as soon as possible if any symptoms of bumblefoot appear on their pets.

Treatment of the disease also includes sanitizing your rat's cage. Owners should remove all rats from the enclosure and take any additional rats to a veterinarian for examination (even if they appear unaffected). Thoroughly clean the cage, taking care to sanitize the entirety of the enclosure along with food and water bowls or toys. Add fresh, soft bedding to prevent future lesions on your pet's feet.

Prognosis for Rats With Bumblefoot

Because the severity of bumblefoot cases can vary, your specific rat's prognosis will depend on its condition and your veterinarian's recommendations for treatment. However, not all pets respond well. Amputation of badly infected toes and feet is sometimes called for in severe cases of bumblefoot. Like other serious infections that are not treated early enough, bumblefoot can be fatal if the animal develops a septic infection. For this reason, early detection and treatment are vital for the best results.

How to Prevent Bumblefoot

Since bumblefoot can be severe and particularly painful, it's important for owners to prevent their pets from contracting this infection in the first place. Thankfully, a few simple methods of caring for pet rats can be effective:

Avoid Trauma to the Feet

Though the factors that lead to bumblefoot are not always present in every case, prevention of trauma or abrasions to the feet is a cornerstone of prevention. Rat owners should consider covering wire floors in their animal's enclosure with a solid surface such as wood, vinyl, Plexiglass, plastic needlepoint canvas, Vellux blankets, or even towels.

Flatter surfaces seem to cause less stress on rats' feet, and will likely result in fewer abrasions that may become infected with bacteria. In addition to walking slower, older rats may also be more flat-footed, so care should be taken to ensure senior pets have soft bedding and surfaces to walk on.

Clean Enclosures Regularly

Keep your rat's cage and bedding meticulously clean and dry. Remove soiled bedding as soon as possible and change it frequently. Using a litter box in your rat's cage can help keep its bedding clean longer, although this method requires patience while rats learn to use it. Sanitize food and water bowls consistently along with planning deep cleans of the enclosure at regular intervals.

Keep Pet Rats Healthy

Prevent your rats from becoming overweight by providing a healthy diet and plenty of opportunities for exercise. Rats' diets should consist of rat block or pellets. To prevent excessive weight gain, try to limit treats (although the occasional supplement is fine). If your rat begins gaining too much weight, consult your small pet veterinarian about dietary options that can help.

Check for Injuries Regularly

Check your rats' feet for abrasions, trauma, or early signs of bumblefoot. This will allow you to detect and treat any wounds early, preventing the painful abscesses and bumps associated with this infection. It may also alert you to potential problems in your rats' cage or bedding, allowing you to correct these issues early and prevent further injuries in the future.

If you suspect your pet is sick, call your vet immediately. For health-related questions, always consult your veterinarian, as they have examined your pet, know the pet's health history, and can make the best recommendations for your pet.
Article Sources
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  3. Bumblefoot (Pododermatitis) in Rodents. Sawnee Animal Clinic.