Bumblefoot (technically referred to as ulcerative pododermatitis) is a complex problem that results from inflammation of the bottom surface of rat feet. A similar syndrome can happen in other animals (especially other rodents, rabbits, and birds). The term bumblefoot generally refers to the stage of the disease when red bumps and lumps form on the bottom of the feet.
What Causes Bumblefoot in Rat Feet?
Typically, bumblefoot starts as a wound that becomes infected (usually with Staphylococcus aureus) from contact with soiled bedding and the cage floor.
This leads to chronic inflammation and abscesses, resulting in bumps on the bottom of the feet that can become quite enlarged. Factors that predispose rats to bumblefoot may include trauma from irregular cage surfaces or roughly textured bedding materials, obesity (which creates increased pressure on the feet and pressure sores), and possibly a genetic predisposition.
Signs of Bumblefoot in Rat Feet
Bumblefoot starts out as small reddened bumps that look a bit like calluses. These bumps can eventually become quite large and may intermittently bleed and scab over. Excessive licking of feet, bloody footprints, or a rat that is reluctant to walk or climb much may indicate that they may have developed bumblefoot.
Treatment of Bumblefoot in Rat Feet
At the first sign of bumblefoot, see your veterinarian. A combination of oral antibiotic treatment along with topical cleaning and treatment of the wounds (as directed by your vet) is usually the first course of treatment.
For bumblefoot lesions that do not respond to this basic treatment surgical treatment may be necessary, but this has significant risks and variable success. Early detection and treatment is vital for the best results (even then, some cases may not respond well). Prevention of bumblefoot is best.
Preventing Bumblefoot in Rat Feet
Though the factors that lead to bumblefoot are complex, prevention of trauma or abrasions to the feet and keeping the cage and bedding meticulously clean are the cornerstones of prevention.
The use of wire floored 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. Owners should consider covering wire balconies with a solid surface (e.g. wood, vinyl, Plexiglass, plastic needlepoint canvas, Vellux blankets, towels). However, even rats kept on solid flooring can get bumblefoot and a theory has developed that exposure to urine pooled on solid floors (especially plastic) may also contribute to the problem. Therefore, it is important to keep all surfaces clean and dry. No matter the cage materials, frequent and thorough cage cleaning appears to be the best defense to bumblefoot.
Roughly textured bedding materials, such as wood chips, may also play a contributing role in bumblefoot. Consider softer alternatives, such as CareFresh to aid in bumblefoot prevention. Remove soiled bedding as soon as possible, and change it frequently. Using a litter box in your rat cage can help keep their bedding cleaner longer.
Prevent your rats from becoming overweight by providing a healthy diet and lots of opportunity for exercise. Older rats may also walk more flat-footed so be sure to provide soft bedding and surfaces for older or weak rats.
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 bumblefoot. It may also alert you to potential problems in your rats' cage or with the bedding that may be able to be corrected to help prevent further problems in the future.