What is fly strike?

During the summer months, pet rabbits allowed to run outdoors might be affected by maggot infestation. Different terms are used for this but fly strike is a common one. Another is to say that the rabbit is fly blown. The technical term your veterinarian might use is miasis. Healthy rabbits are generally not affected by fly strike. There are three main problems that lead to the condition. First, a wound to which the flies are attracted and on which they lay their eggs is an obvious site where maggots can cause damage. More commonly, a rabbit that cannot, or does not feel like turning round to groom itself will quickly have matted and soiled fur around its anus. This, from the fly's point of view, is an ideal opportunity to lay eggs.  When the maggots hatch and if the rabbit cannot groom itself, these fly larvae survive, spread and may cause a tremendous amount of damage as they eat through the tissues. Thirdly, damp bedding is an ideal environment for egg-laying and maggot growth and development.

Ensuring your rabbit is not prone to fly strike

The key factors in preventing fly strike are to ensure that bedding is dry, that the rabbit does not have any wounds or ulcerated areas of skin and that there are no problems to prevent him from grooming. What are these likely to be?

Dental disease can cause inability to groom. An animal which has sharp hooks on its molar or cheek teeth will not want to groom since these hooks cause pain when the rabbit extends its tongue to groom in the normal manner. Similarly, overgrown incisor teeth (at the front of the mouth) will impede grooming. Your rabbit's teeth should be checked regularly by your veterinarian and appropriate treatment given if necessary.

Rabbits with back problems may not be able to turn around to groom properly. Any rabbit with diarrhea will be especially prone to fly strike, and will have many other problems associated with the diarrhea.

Treatment for fly strike

The animal will need to be sedated or anesthetized so that all the maggots can be removed and the whole area well disinfected with an antiseptic solution. Your rabbit will need antibiotics since there is a major probability of secondary bacterial involvement. In severe cases intravenous fluids and steroids may be needed. In such cases your rabbit will be hospitalized and kept warm and comfortable, probably with a heating pad or an overhead infrared light. Such intensive care may cure your rabbit of the maggot infestation but in severe cases extensive surgery may be needed to remove all the dead maggot-ridden tissue. This can be a long, quite risky and often expensive treatment and after all that, it will still be necessary to overcome the original problems which led to the fly strike.

Preventing fly strike

The preferable option is to take your rabbit to your veterinarian twice yearly for a routine health check, to ensure that dental disease or back problems are not predisposing your rabbit to this dangerous condition. Giving your rabbit dry and well-aired housing is an ideal, cheap and easy way to minimize the possibility of fly strike.

This client information sheet is based on material written by Shawn Messonnier, DVM..