If you call it rabbit bladder sludge or Urolithiasis, you will agree that the issue is critical. It is suffered by all breeds of rabbit and age. This has been the concern of many vets and owners. Much research has been done and much is ongoing about why rabbits develop bladder sludge. There is no precise answer yet.

But general knowledge is that rabbit bladder sludge is a critical problem. Rabbit bladder sludge is a problem in the urinary bladder. This makes the urine thick. Its tendency to reoccur after treatment makes it frustrating. Recent advances in veterinary medicine have helped grasp how it could be tackled.

This issue is caused by many factors. This article will explain in detail the causes, treatment, and preventive measures. Keep reading!

What is rabbit bladder sludge?

Rabbit bladder sludge or Urolithiasis refers to the presence of blockage in the urinary tract of a rabbit. This then increases the pressure in the ureters. Different organs make up the urinary tract. What makes rabbit bladder sludge complicated is that it could develop in any part of the urinary tract. The common organ where it occurs is the urinary bladder and kidney.

In most cases, thick bladder sludge is found in rabbits. It might seem normal, but it is a sign that the rabbit is not in perfect health condition. It can occur in any sex and breed of rabbit. It also indicates that the diet of rabbits contains a lot of calcium. Moreover, it could also mean that the rabbit is not hydrated.

Causes of rabbit bladder sludge

rabbit bladder sludge
Rabbit bladder sludge

Many factors have been identified as the possible causes of rabbit bladder sludge. Rabbits that are fed the same diet and live the same lifestyle might both not have the issue. Highlighted below are some of the common causes of rabbit bladder sludge.

High concentration of calcium in the rabbit’s diet

What you feed your rabbit is an important factor that determines how well they will live. A rabbit fed with a diet of high calcium is at a higher risk of developing rabbit bladder sludge. Feeding an adult rabbit with a high concentration of calcium is risky. The only time they could need it is during pregnancy or while nursing a young rabbit. Alfalfa hay, spring greens, spinach, and carrot tops are examples of diets with high calcium.

Kidney disease

Rabbits might not show signs of kidney disease early. Most that look healthy might have a reasonable degree of a kidney ailment. This is because kidney disease will not appear in the blood work until over 70% is lost. The implication of this is that rabbits suffering from kidney disease won’t be able to absorb the needed calcium for the body. The residual calcium will build up over time and it could cause a rabbit bladder sludge.

Low intake of water

The amount of water intake is connected to the quantity of urine. When the rabbit takes a lesser quantity of water, there will be a high concentration of calcium in the little urine. Rabbits might take a lesser quantity of water during winter due to the freezing of the water bowls. When this happens often, there is a high risk of bladder sludge.

Lack of where to urinate

When there is no place to urinate, rabbits would hold urine in their bladder. Doing this will allow a high concentration of calcium to settle in the bladder. This could block the bladder in the long run. Ensure that you create a place for urine in the rabbit’s shelter.


A rabbit that is overweight is not living well. In most cases, it is difficult for the overweight rabbit to adopt the best position for urinating. Moreover, they could have weak muscles around the bladder. The implication of this is that it will be easier for calcium to settle in the bladder. Also, overweight rabbits find it difficult to empty their bladder due to pain.

Inflammation of injury to the ureters

An injury could occur in any part of the rabbit’s body due to different factors. An undetected or untreated injury to the ureters could swell up and block the normal flow of urine.

Symptoms of rabbit bladder sludge

The symptoms of rabbit bladder sludge vary from one rabbit to another. Some might exhibit severe pain signs while some rabbits will act normal. The following are some common signs.

  • Frequent urination in a small volume
  • Signs of pain while urinating
  • Traces of blood in the urine
  • Obesity
  • Inactivity
  • Difficulty in emptying the bladder

Diagnosis of rabbit bladder sludge

Unless you are a professional, you cannot detect a rabbit bladder sludge. Diagnosing a rabbit will need the service of a vet. Here is some diagnostic process.

Signs and history of the issue

You are the one caring for the rabbit. You should have some helpful information for the vet. What you say to the vet is crucial in diagnosing the disease. If possible, you can take note of the changes you notice and when you suspect that something was wrong.

You should not hide any information about the history of the rabbit also. This includes previous records of ailment, and a change in the hutch, diet, and lifestyle of the rabbit. You should also state the home remedy you have taken to treat the ailment and other helpful ideas.

Physical examination of the rabbit

A vet will have to do a thorough physical examination of the affected rabbit. This will help to know if the rabbit has bladder sludge. It is possible to feel if a rabbit has bladder sludge by examining the hindquarters. This is only possible when the rabbit is corporative, and the issue is at an advanced stage.

The benefit of a physical examination is that it would reveal the condition of the rabbit. In the process, other underlying medical conditions could be discovered. For instance, dental disease, weight loss, pains, and other abnormalities could be discovered.

Sample testing of the urine

Chemical composition and abnormal cells could be revealed through testing of the rabbit’s urine. The vet would collect the sample for lab testing.

Treatment of rabbit bladder sludge

The method of treating rabbit bladder urine varies. The right method for the rabbit will depend on the severity of the sludge, the age of the rabbit, and the current medical condition. Whether totally or partially blocked bladder, the rabbit requires urgent medical attention. The method of treatment includes the following.


The severity of the disorder will determine if surgery is necessary. The truth, however, is that there is currently no diet that can dissolve a rabbit bladder sludge. Also, the size will increase with time if not surgically removed. It could also subject the life of the rabbit to risk.

Before the vet opts for surgery, the kidney of the rabbit will be examined. This is done to avoid complications. How soon the rabbit will be discharged depends on the surgery and how the rabbit is responding.

Catheterization and flushing of the bladder

The rabbit bladder sludge is also treatable by flushing the bladder. This method involves the use of a catheter and saline. The vet will place a catheter into the rabbit’s bladder and then flush it with saline. This will dissolve the sludge material in the bladder. The diluted material could be extracted through a syringe or manually by pressing the bladder. The method will be repeated until the sludge concentration in the bladder is reduced.

Use of antibiotics

The use of antibiotics is usually prescribed by the vet after surgery or catheterization of the bladder. This is appropriate if the vet suspects the possibility of a bladder infection after the treatment.

Increased water consumption

The treatment of rabbit bladder sludge is not complete without Diuresis. This is required so that the urine production of the rabbit will increase. This means that residual sludge in the bladder will be diluted and flushed out during frequent urination. Diuresis also reduces the chances of recurring sludge.

Vitamin C

Vitamin C is prescribed and administered after to aid the healing process of the urinary tract tissue. Also, vitamin C is needed for the rabbit to gain lost ascorbic acid during the stress of the surgery.

Pain reliefs

If the vet is opting for surgery or catheterization, the rabbit needs pain relief during and after the surgery. Once the rabbit returned to normal life after the surgery, the use of pain relief could be discontinued.

Care for recuperating rabbit

In most cases, a recuperating rabbit requires care during treatment so that it can urinate without issue again. Follow-up treatment facilitates quick recovery and also prevents recurrence. Below are some caring tips you can show your rabbit while recuperating.

Isolate the rabbit

If you have more than one rabbit, you should isolate the affected one. This is not done because of the risk of passing the disorder, it is done to ensure that the recuperating rabbit is not stressed. Ensure that the new shelter is neat and habitable for the rabbit.

Proper diet

The high concentration of calcium in the diet is one of the common causes of bladder sludge. You should ensure that the rabbit is not feeding on a diet with a high concentration of calcium during recovery.

Scheduled medication

Any medication prescribed or given to you by the vet should be administered at the appropriate time. There are instances where the rabbit will show signs of full recovery without completing the dosage. It is recommended that you complete the dosage as prescribed by the vet.

Consult a vet

You need to cooperate with the vet for the complete recovery of your rabbit. Ensure that you communicate often. You can report any observation and also ask for more guidance.

Prevention of rabbit bladder sludge

Any breed and sex of rabbit could have bladder sludge. Though treatable, it tends to happen again. The good news is that it is preventable. Below are some helpful tips on how to prevent rabbit bladder sludge.

Ensure high water intake

A high intake of clean water will dilute the urine, and reduce the concentration and formation of sludge. You can achieve this by ensuring that all water bowls are filled with water all the time. Moreover, you should change the water daily.

Ensure healthy living

The living and sanitary condition of the rabbit is very important. It is a factor that determines if they will get sick or not. With improved living conditions, you are decreasing the chances of bladder sludge. For instance, ensure you use vet beddings that would drain urine and other fluids.

Moreover, keeping rabbits indoors would improve their sanitary condition. If you are keeping them in a closed shelter, periodic cleaning of the place is essential. Also, make sure the rabbit can move around in the shelter.

Allow your rabbits to exercise

Like how exercise is helpful to humans, it also helps animals. If you allow your rabbit to exercise, urine sediments and calcium residual in the bladder will shake. This will prevent the formation of sludge in the bladder. Moreover, exercise will increase the urge to urinate.

Offer a variety of feeds

There are many packaged treats for rabbits on the market. Most of these feeds contain nutrients that might not be beneficial to your rabbit. This would likely increase the risk of bladder sludge. Instead of a packaged treat, you should increase the fresh green intake of your pet. A fresh green diet also increases water intake and supplies other nutrients.

However, if you are introducing a new duet, you should do it gradually. A variety of grass is another way to ensure that rabbits get different nutrients.

Trust a vet

You need to trust a vet for proper nursing of your pet. You will get professional guidance and tips from a vet. Moreover, periodic check-ups of the rabbit will reveal any potential health condition. Proper steps will then be taken for treatment.


There are instances where you cannot prevent the development of sludge. But if you implement the message in this article, you can reduce the chances of recurrence in your rabbit.

About the Author

Anoop Nain

I am Anoop Nain, proud father of four rescued dogs and two Flemish giant rabbits. I have a degree in Animal Behavior and Welfare. Besides being a full-time dog father, I am an NGO worker and content writer and an educationist, with more than 6 years of experience. It is while working with the NGO I got an opportunity to educate people on animal rights, pet healthcare, animal welfare and various other issues pertaining to animals.

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