Cancer of the uterus (or womb) is very common in rabbits; in fact, it is probably the single most common tumour in rabbits even though it affects only females. It is usually highly aggressive and rapidly spreads to other abdominal organs and into the lungs.
Essentially, being a female rabbit! Evolution has equipped rabbits with the capacity to breed fantastically fast, but in doing so, the female reproductive tract is so “overactive” that the uterine wall undergoes metaplasia (cells changing form) and then neoplasia (formation of tumours). The most common is an aggressively malignant uterine adenocarcinoma.
Any unneutered female rabbit. Statistically, about 4% 80% of does will have uterine tumours by the age of 2 years, rising to 80% at 6 years. Overall, we’d expect 60% of ALL unneutered female rabbits over 3 years of age to have tumours in their uterus. It doesn’t seem to matter whether they’ve been bred or not, or what breed they are, the risk appears to be linked to age, not reproductive function.
Once the tumour grows large enough, it will definitely cause symptoms; typically, these include bloody urine, a discharge of blood from the vulva, weight loss and sometimes abdominal swelling (due to the tumour growing). If the tumour spreads to the lungs, coughing, wheezing and difficulty breathing may be apparent, but usually there are no signs immediately.
An ultrasound scan will often identify an abnormal mass in or on the uterus; the presence of a tumour can then be confirmed by exploratory surgery. Secondary tumours in the lungs can only usually be detected with an X-ray, but they may not be visible until they have grown to a significant size (so a “clear” X-ray doesn’t mean there aren’t microtumours in the lungs that are too small to see yet).
The only treatment is surgical removal of the uterus and ovaries – however, if the tumour has spread before it can be removed, the prognosis is poor.
Yes, very simply – spay all female rabbits not required for breeding as soon as possible after puberty (usually, at about 5-6 months of age). No uterus = no uterine tumours. Other than this, there are no lifestyle modifications or treatments known that will prevent or slow down the growth of the tumours.
RHD, or Rabbit Haemorrhagic Disease, is a serious and usually fatal infection of rabbits. It is also known as VHV (Viral Haemorrhagic Disease), and sometimes RCV (Rabbit Calicivirus), and there are two variants – RHD1 (which usually causes sudden death) and RHD2 (a newer variant which has only relatively recently been recognised).
RHD is caused by a type of virus called a calicivirus, that is shed by infected and (although it’s rare) any who manage to survive the infection. The virus is immune to freezing, and stays stable at room temperature for over 3 months (and longer if it’s cold weather). As a result, it can easily be spread from infected wild rabbits to domestic pets, and even to house rabbits, with the virus particles being carried on people’s shoes, clothes and even skin. Rabbits that are lucky enough to recover can usually be expected to shed the virus for 6 weeks or longer.
Any rabbit is potentially at risk if preventative precautions aren’t taken.
The most common symptom of RHD1 is sudden death – rabbits that appear healthy may suddenly drop dead from the infection without showing any other signs. Sometimes, a rabbit survives longer, and then they will be depressed and lethargic, have a fever, and bleed from the nose or mouth. Very occasionally, a rabbit will recover, but this is unusual. RHD2 is much more variable – sudden death (sometimes with and sometimes without bleeding) is sometimes seen, but more often the rabbit will be ill for several days, perhaps even a week or more, before succumbing. This, of course, dramatically increases the risk that other rabbits will become infected because as long as they are alive, they’ll be spreading the virus.
The clinical signs are characteristic, but not strictly speaking enough for a certain diagnosis. Unfortunately, in most cases the only way to confirm a diagnosis of RHD is by post-mortem examination, because these rabbits do not usually survive long. In living rabbis, blood samples can be sent away for virus isolation testing.
There is no treatment for RHD1 or RHD2 – most rabbits will die; those that survive do so because their immune system is able to meet and defeat the virus. In most cases, we would strongly recommend that infected rabbits are put to sleep on welfare grounds, and to prevent further rabbits becoming infected. If a rabbit has a very mild case, it is possible to attempt supportive treatment with fluid therapy and anti-inflammatory drugs, but the risk of complications is high.
Yes – there are vaccines available for RHD1 and (now) RHD2. It is essential, however, that these vaccines are kept up to date, as immunity does reduce over time. In addition, you can minimise the risk of infection by keeping your rabbits isolated from wild ones (as well as birds and rodents that can carry the virus), for example, in a secure double walled hutch, or as a house-rabbit. However, as there is always a risk of bringing the virus into the house, unless you are able to institute full biosecurity precautions (such as foot dips and changing clothes whenever you visit your rabbits), this alone will not be 100% effective, so we would still recommend vaccination.