ABSTRACT: The aim of this article is to provide a brief overview of rabbit fleas ISpillopsyllus cuniculi), their life cycle and the treatments and control measures that can be utilised to treat and prevent infestation in rabbits. S. cuniculi can also be a major vector for the transfer of myxomatosis, so it is important for veterinary nurses to educate owners about the risk fleas pose to rabbits and also to encourage vaccination against myxomatosis.
Rabbits can be affected by a wide variety of ectoparasites that can potentially cause serious health problems. This is especially true of rabbit fleas (Spillopsyllus cuniculi), which can act as a vector for myxomatosis. Veterinary nurses can play a vital role assisting with their diagnosis and advising owners on the best preventive measures needed.
With rabbits currently being the third most popular pet in the UK, it is just as important for VNs to discuss flea control in rabbits as it is for dogs and cats, as well as relaying its importance to clients.1
This article will describe S. cuniculi and outline the treatments and control measures available, before highlighting the dangers of myxomatosis if S. cuniculi is not controlled and rabbits are not vaccinated.
It is important to note that although cat fleas (Ctenocephalides felis felis) are the most common flea affecting pet rabbits (Figure 1) – especially in multiple pet households – rabbits can be affected by rabbit fleas, particularly if they have contact with wild rabbits which may also be myxomatosis carriers.2
Figure 1: Cat flea ICtenocephalides felis felis). (Image copyright Bayer Animal Health)
Description and diagnosis
S. cuniculi are blood-sucking insects which, if present, will normally be located around a rabbits ears causing scratching and head shaking.3 They can also cause patchy alopecia, pruritus and crusty lesions around the face and ears, and can be identified by direct visualisation of adult fleas.
Furthermore, coat brushings from the rabbit can be placed on to damp white paper to establish whether red patches created by flea excreta or ‘dirt’ are present.4 If an adult flea can be isolated, microscopy may be used to identify the species present. S. cuniculi has a genal comb at an oblique angle with four to six spines, as opposed to C. felis felis which has between seven and eight spines.5
The life cycle of S. cuniculi is very similar to that of other fleas – adults lay eggs which hatch into larvae before pupating and then hatching into adults. However, in this case the life cycle is thought to be regulated by the rabbits hormonal cycle during pregnancy. Increases in oestrogen in the rabbit s blood stimulate fleas to mature and produce eggs.
S. cuniculi will actively move from bucks and non-pregnant does to pregnant does, because without feeding on blood from a pregnant doe they will be unable to produce fertile eggs. Accordingly the flea population increases dramatically during the rabbit breeding season.3
Treatment and prevention
Infestations can easily be treated with strict flea control. Imidacloprid (Advantage, Bayer) is a spot-on treatment which is licensed in the UK for rabbits and can be used to treat flea infestations.67 All other rabbits housed with the infected rabbit should also be treated; as well as other animals in the household, including dogs and cats, as they can pass fleas on to rabbits and vice versa.
Lufenuron (Program, Novartis) is an insect growth regulator and has also been reported as a safe and effective form of flea control in rabbits. However, this is not licensed in the UK for rabbits.6'7 Although fipronil (Frontline, Merial) is used successfully in cats and dogs, it must not be used to treat rabbits, as it can cause adverse reactions including ‘anorexia, lethargy, convulsions and death'.8 Following an infestation – as well as treating the rabbit and other pets in the household – it is important to clean the rabbits accommodation (whether indoors or outdoors) by disposing of all bedding and giving hutches and runs a thorough clean.
Environmental insecticide sprays may also be useful directly on the rabbits accommodation and, if necessary, within the house to help kill all stages of the flea life cycle. However, this should be done with caution and the manufacturers’ instructions must always be followed. It is also essential to ensure that pet rabbits are not exposed to wild rabbits, because they can be myxomatosis carriers, and fleas may be able to transfer the disease to pet rabbits.
As long as the above measures are taken, long-term flea preventive treatments should not be necessary;3 but if this is found to be necessary, permethrin (Xenex Ultra Spot On, Genetrix) and ivermectin (Xeno Products, Genetrix) are both marketed for the prevention and treatment of external parasites and are suitable for rabbits under the Small Animal Exemption Scheme.6
Myxomatosis summary
As previously mentioned, rabbit fleas are important vectors for myxomatosis, which is why flea control should be taken very seriously. Regular vaccination against the virus should also be encouraged.7
Myxomatosis is a fatal disease; with death normally occurring within two weeks of infection. There is very limited success in treating the disease, so prevention is vital.2 It is characterised by skin lesions/nodules around the body – especially the face and ears – followed by swelling of the eyelids and purulent ocular discharge, which effectively blinds the rabbit (Figure 2). Death usually occurs as the result of secondary bacterial infection overwhelming the infected rabbit.2'9
Figure 2: A rabbit with mxyomatosis (© Richard Harvey.)
Nobivac Myxo (Intervet/Schering- Plough) is currently the only vaccine against myxomatosis licensed in the UK. It can be administered to rabbits from six weeks of age, with the onset of immunity being established two weeks after vaccination. This vaccine should ideally by administered intradermally and will provide immunity against myxomatosis for six months and, therefore, boosters will be required twice a year, especially in locations where wild rabbits are common.6
Conclusion
Flea control in pet rabbits should be taken seriously as a means of reducing the prevalence of myxomatosis and there are a number of ways in which this can be achieved. King states that rabbit clinics can be a very effective way for VNs to educate owners, not only about parasite control and vaccines, but also about general care and good husbandry.10
It is, therefore, vital that VNs are knowledgeable about these subjects. This could, in turn, improve rabbit welfare and protect rabbits from potentially fatal diseases.
Author
Hanna Buckoke BSC (Hons) RVN MBVNA
Hanna graduated with a Degree in Veterinary Nursing from the RVC/Middlesex University/College of Animal Welfare in 2011. This is where she gained an interest in parasitology. Since then she has carried out locum work at various veterinary practices across London.
To cite this article use either
DOI: 10.1111/j.2045-0648.2012.00147.x or Veterinary Nursing Journal Vol 27 pp 57-58
References
1. RSPCA [2011] Rabbits, [online]. RSPCA Available from www.rspca.org.uk/allaboulanimals/pels/rabbits [Accessed 22.2.11]
2. MEREDITH. A [2006] Dermatoses' in A. Meredith and P Flecknell [eds] BSAVA Manual of Rabbit Medicine and Surgery. [2nd ed I Gloucester: BSAVA. 129-136
3. TAYLOR. M A., COOP. R. L and WALL. R L. [20071 Parasites of laboratory animals' in M A. Taylor, R. L Coop & R L Wall Veterinary Parasitology. 13rd [ed] Oxford: Blackwell Publishing Ltd. 604-651.
4. HOPPMANN. E. and BARRON. H. W. [2007] Ferret and Rabbit Dermatology·. Journal of Exotic Pet Medicine. 16(4): 225-237.
5. FISHER, M and McGARRY, J. [2006] Focus on small animal parasitology. Leverkusen Bayer Healthcare AG.
6. NOAH 120101 Compendium of Data Sheets for Animal Medicines 2011. Middlesex NOAH.
7. WHITE. S. D , BOURDEAU, P. J. and MEREDITH, A [2002] Dermatologic Problems of Rabbits' Seminars in Avian and Exotic Pet Medicine. 11(3|: 141-150.
8. WEBSTER. M. 11999) Product warning: FRONTLINE' Australian Veterinary Journal 77:202.
9. HARCOURT-BROWN, F [2002] Skin diseases', in F. Harcourt-Brown Textbook of Rabbit Medicine London: Butterworth Heinemann, 224-248
10. KING, C [2011] Running rabbit clinics Veterinary Nursing Journal. 26: 25-27
Veterinary Nursing Journal • VOL 27 • February 2012 •