Samples - how they help your vet
Blood collection tubes
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Blood collection tubes
Laboratory tests are used by vets to help them diagnose disease in sick pets. Increasingly they are also used as part of a routine health check to detect hidden disease before the development of obvious symptoms. This allows your rabbit to be treated earlier and more effectively. Tests may be used to show whether a rabbit is carrying infections that could pose a threat to other rabbits it comes into contact with.
Who carries out the test?
Many veterinary practices have their own small laboratory where a limited range of tests can be carried out. Results are obtained quickly which allows rapid decisions on treatment (often a quick test is carried out in the practice and a sample is then sent to the commercial laboratory to check that the results tally). If a broader range of tests is required, samples will be sent to a commercial laboratory which will usually send results of routine tests back to your vet by fax, telephone or e-mail within 24 hours (although some tests may take 10 days or longer to complete). Commercial laboratories are able to advise your vet on how to interpret difficult test results. Occasionally, especially if samples are delayed in the post, they may deteriorate, and your vet may need to repeat the test.
What is being tested and why?
There is a whole battery of tests which can be done on different types of sample, although not all are used to investigate every disease. Some samples are easier to obtain than others and the effects that testing has on your rabbit will vary.
The tests are:
- Blood tests: it is possible to tell a great deal about your rabbit's health or disease from the concentration of different chemicals in the blood. The proportion of different types of blood cells and the presence of proteins called antibodies (which are produced as part of the body's defence against disease) may tell your vet how well your pet is fighting the disease. Samples are usually taken from a vein in the ear using a hypodermic needle and syringe. A patch of fur over the vein is shaved and disinfected with surgical alcohol to clean the skin and allow your vet to see the vein more easily (a few millilitres (about a teaspoon) of blood are put into special containers to prevent it clotting). Taking a blood sample does not hurt your rabbit although some rabbits don't like being held while the sample is being taken. Some bruising may occur if your rabbit has delicate skin or struggles when the sample is being taken. The puncture hole will heal quickly.
- Urine tests: these are carried out to check for diseases such as cystitis or bladder stones. The presence of proteins or sugar in the urine will indicate whether the kidneys are functioning properly. Your vet may be looking for signs of an infection in the kidneys or bladder. Urine samples can be collected by providing your rabbit with a clean, empty litter tray and waiting! Collect the urine in a clean screw-top bottle (your vet can provide you with these) and refrigerate - this needs to be taken to your vet as soon as possible. When it is not possible to wait for a naturally produced urine sample your vet may collect one using a needle inserted into the bladder through the skin over the belly or via a catheter passed into the bladder. It is often possible to collect samples in this way without sedating your rabbit.
- Faeces (droppings): small samples of faeces often help to identify diseases of the digestive system. The sample can be tested (culture) to see if any unusual bacteria grow indicating an infection in the intestines.
- Swabs: a rabbit's eyes, ears, nose or skin can often become infected with disease-causing bacteria, viruses or fungi. Swabs are taken by gently rubbing the affected area with a small piece of cotton wool. The swab is then either transferred onto a glass slide for examination under a microscope or cultured in the same way as a sample of faeces. The results of a culture test may take a few weeks, or longer in the case of some slow growing bugs.
- Skin scrapings: rabbits with skin disease will be tested to see if they are infected with parasitic mites. The skin is scraped gently with the edge of a scalpel blade until bleeding occurs. This may cause minor discomfort to some rabbits although others tolerate it fairly well. There are usually only small numbers of mites and a large number of scrapings may have to be taken from several areas before finding them. The skin sample is transferred to a glass slide and examined under a microscope.
- Tissue biopsies: if a rabbit has a growth on its body it is normal to take a tissue biopsy - removing a small part of the lump which is examined under a microscope to see what sort of cells it contains. Fluid samples may be taken from the airways via a tube placed in the throat, or the digestive system via an endoscope passed into the stomach. In this way your vet can obtain more information without performing a full operation on your rabbit.
How many tests are needed to diagnose a disease?
With many diseases it is not possible for your vet to come up with an instant diagnosis. Your animal may have to undergo a number of tests so that your vet can rule out possible causes of the illness. While some diseases can be confirmed using a single test, others will need a large number (profile) or a sequence of tests on one or more tissues or body fluids. There are occasions when repeat tests may be needed, for example, looking for changes in antibody levels in the blood over time.
Your vet may need to perform diagnostic tests on your rabbit, or on samples from your rabbit to help him provide the best possible care for your pet. If you are unsure what a test involves or why your vet needs to do it, please ask for more explanation.