Teresa L. Lightfoot, DVM, DABVP-Avian
Rabbits tend to develop large and extensive abscesses. Lacking the enzymes needed to break down or liquefy the purulent material (pus) in these abscesses, the resultant material is thick and difficult to drain. The rabbit’s body responds to these infections by forming an extensive capsule around the abscess. This encapsulated area is very vascular, and often adherent to important underlying structures, such as facial nerves, blood vessels and bones of the teeth and jaw.
Therefore, unlike abscesses that occur in cats, abscesses in rabbits tend to be difficult to treat and frequently recur. Treatment usually involves multiple steps:
1. Depending on the location of the abscess and the age, general health, and any other concurrent medical problems of your rabbit, blood work, X-rays and or ultrasound testing may be necessary. Frequently, the tooth roots of the upper or lower molars or the major incisors are involved in abscesses around the head and neck, and tooth trimming or tooth extraction may be necessary.
2. Antibiotics administered systemically (either oral, injectable or both).
3. Surgical debridement of the abscess (removal of as much of the contaminated tissue as possible).
4. Determining by cytology (which can be done at the same time as the surgery to drain the abscess) the general type of bacteria involved, and therefore the best class of antibiotics to use until and unless a culture of the material provides more information.
5. Implantation of methyl methacrylate antibiotic impregnated (MMPA) beads into the abscess to allow constant release of antibiotic directly into the affected area.
6. After surgical debridement, the area must be treated as an open wound with extensive home care required, including daily flushing of the wound.
The implantation of antibiotic impregnated beads (MMPA beads) has shown tremendous promise in the treatment of these persistent abscesses. The original use of this material, which is also commonly known as bone cement, was for infected fractures and prevention of infection during surgical hip replacement in humans. Therefore, much research has been done on the types of antibiotics that are most effective when delivered in this manner and the duration of their elution, or release, into the local tissue. Results can vary according to the rabbit’s other existing problems and the extent of tooth and bone involvement in the abscess. Oral antibiotics, or injectable penicillin are often used concurrently.
Since rabbits, being inherently a prey species, tend to react to pain, fear or other stressors with the release of adrenaline, (which is very detrimental to the rabbit’s kidney and GI function) analgesia is an important part of the treatment for rabbit abscesses.
In addition, it is critical in rabbits that the appropriate caloric intake be maintained. If your rabbit is not eating normally, you will be given instructions on syringe feeding to ensure that gastric bloating, infection and secondary endotoxemia (known as dysbiosis in rabbits) does not occur.
For more information on this subject, speak to the veterinarian who is treating your pet.
© Exotic Veterinary Seminars 2001