Presenter – Professor Stephen D. White, DVM, Department of Medicine and epidemiology, University of California
Skin problems in rodents and rabbits are one of the more frequent clinical presentations in these species that we encounter in practice. It used to be that reaching for a bottle of ivermectin was the standard approach to any ‘small furry’ inflicted with a dermatological ailment. However this area of veterinary medicine continues to move forward and Professor Stephen White led a veterinary webinar discussing the current thinking on managing dermatology cases in rabbits and rodents, providing a practical and informative session useful for any small animal vet in practice.
Stephen discussed a number of dermatological conditions categorising them into pruritic, alopecia without pruritus, scaling and nodular diseases. One of the most common causes for pruritus in rabbits and rodents is the ectoparasite. Psoroptes cuniculi is one of the more common parasites found in the rabbit, often affecting their ears. Rabbits get an excess of debris within their ear canals when affected by Psoroptes and in order to diagnose the offending mite, some of this debris can be mixed with liquid paraffin and mites can be looked for under the microscope. Except for removing the debris to make a diagnosis Stephen advised that rabbits ears should not be cleaned as recommended in dogs as it is very painful and generally does not help.
One of the most common causes of pruritus encountered in the guinea pig which most vets will have encountered is Trixacarus caviae. What is interesting in these cases is that you can have one very badly affected guinea pig in contact with another guinea pig which is showing no clinical signs at all. This demonstrates the varying degrees to which individual guinea pigs react to the mite, and Stephen advised always treating all in-contact animals regardless of whether they are showing clinical signs.
Stephen explained that in the USA the drug selamectin has replaced treatment with ivermectin for both Trixacarus and Psoroptes as well as other mites in rodents such as Notoedres. Obviously in the UK the cascade has to be adhered to but selamectin can also be an effective treatment and Stephen has made the dose rates for the various species available as a download on ‘The Webinar Vet’.
Diagnosing dermatological cases in these species can prove in itself to be challenging because of their size and sometimes the ferocity of their pruitus. Guinea pigs can sometimes have a seizure like reaction if severely affected by mites, and trying to skin scrape these animals or perhaps smaller rodents such as rats and mice can be difficult as there is a reasonable chance you could cut them if using the standard scalpel approach. Under these circumstances Stephen likes to use a flat medical grade spatula to perform skin scrapes, an approach which is much less likely to cause trauma.
Stephen’s webinar was so crammed full of useful information I have only been able to mention some of the advice given to us about one of the categories mentioned earlier, pruritus. There are three more categories I haven’t discussed that are equally as interesting and equally as useful to any small animal vet. This veterinary webinar not only provides a useful refresher for those of us who need it, but also provides a great way to ensure that you are up to date on diagnostics and available treatments for managing dermatological cases in rabbits and rodents.
The Stethoscope (MRCVS)