Pet rabbits may be affected by a maggot infestation caused by flies. Blowflies like to lay their eggs on material that will provide their larvae with food as they develop. When your rabbit has a dirty bottom, soiled with either urine or faeces, it is a perfect place for blowfly eggs to grow. Some rabbits rarely get a dirty bottom; they groom themselves carefully and always move away from where they have just urinated or passed a motion, however there are exceptions.
Which rabbits are at risk?
If your rabbit has problems with overgrown incisors or molar teeth they can not groom properly or chew their food well, which often causes them to have softer faeces or diarrhoea.To a rabbit this isn’t as pleasant to clean and more difficult as well.
Rabbits on an inappropriate diet that is too high in easily digested carbohydrates, i.e. biscuits, bread and rich fruit stick treats will often develop diarrhoea as they cannot digest these unusual sources of carbohydrate. This disturbs the population of bacteria and protozoa in the gut.
Overweight rabbits have problems reaching their bottoms to clean them allowing a build up of sticky pellets which attract flies.
Older rabbits and those becoming less mobile will also have potential problems with dirty bottoms as they are not so likely to move away from the areas where they pass urine and faeces and may get residue stuck to their fur.
In very rare cases maggots can develop in areas where there is excess moisture or discharge, such as around the eyes if they have conjunctivitis, or nose if they have dental problems.
What are the signs of fly-strike?
Your rabbit may just have a dirtier bottom than usual, or be more obviously smelly when you clean their cage.
You may see tiny white flecks 1-2 mm in length, which are the fly eggs on the fur of the rabbit’s bottom and between its legs or on its rump. Overnight these can hatch into young maggots.
The young maggots grow rapidly into mature maggots. Once the maggots are mature they start burrowing into the rabbit’s skin around the groin and base of the tail and eventually can penetrate into the muscle and fat underneath causing great pain and discomfort.
By this stage the rabbit will be very subdued and smell horrible. Its bottom will be moist and the skin will often be easily separated from the flesh underneath, where the maggots have eaten under the skin attachment.
Although some rabbits can be treated very successfully in the early stages of fly-strike, the ones with severe muscle damage and skin trauma find it more difficult to recover.
What can be done to prevent Fly-Strike?
All rabbits are at risk of fly-strike but there is a considerably higher risk during the warmer summer and autumn months. Always ensure that the rabbit hutch is clean so that it does not attract flies, and make sure that the hutch is away from areas frequented by flies such as the dustbin or compost bin.
It is a good idea to make a habit of checking your rabbit’s bottom every day, even during the winter. If you practice turning over your pet rabbit from the first day you get him it will soon become an acceptable part of his routine to be examined for signs of sticky faeces or urine staining.
If your rabbit’s bottom is dirty, clean it off under a warm tap or in a warm bath, with a mild shampoo and dry him off well. If the sticky bottom persists then your rabbit should be checked by the vet. A sponge on application called Rearguard can be used to soak your rabbit’s fur and will prevent maggots developing. Fly repellents in the hutch, such as citronella plants, may also help deter flies.