Blood tests are a way to get information about your pet’s health that can only be found by collecting blood and analyse it. Because your pet cannot tell us how it is feeling, or where the pain is, we rely on testing various things in order to help find the problem and start treatment as soon as possible. Blood tests are an incredibly valuable tool in a vet’s toolkit to detect, identify and treat diseases.
How do we collect blood from your pet?
When we need to get a blood sample from your pet, it depends what test we need to run to determine where we need to draw the blood from. For most tests, we would draw blood from your pet’s jugular vein in the lower neck area or from the cephalic vein in your pet’s front leg. If we are simply doing a blood smear, we just need a teensy tiny drop of blood which is best taken by a pinprick to the ear, or sometimes the tip of the tail. For blood cell counts, or testing certain organ issues like checking for kidney or liver disease, we need quite a bit more blood, and will then need to go for a bigger blood vessel, like the jugular. Because animals have a thick layer of hair over their skin, we usually need to shave a small area of hair in order to see the vein properly. We then disinfect the area with an alcohol swab and collect a small amount of blood from the vein with a needle and syringe. The sample is then placed in special tubes and processed either at our clinic or it gets sent off to an external lab, depending on the test needed.
Why do we want to do blood tests on your pet?
There are literally hundreds of blood tests we as vets can perform on your pet, but we will normally narrow it down to a small list based on what we find on our physical exam, or what our concerns are.
My dog is healthy, why should I have the blood tested?
In adult dogs, it is a good idea to establish a normal baseline for each individual pet. Some pets have naturally lower blood cell counts than others, and it is good to have a “normal” result as a baseline for your specific pet should he/she ever get ill. By seeing what is normal for your pet, we can in future quickly establish an abnormal result and pick up subtle changes early.
Why else do we do blood tests? Is it really necessary?
In sick patients we cannot always get all the information we need from examining your pet in a consult room. Take anemia (lack of red blood cells) for example: even though we can see your pet is pale by looking at their gums, in most circumstances we cannot figure out the cause and severity of the anemia without doing a blood test of some sort. No matter how hard we listen to the heart, or how much we feel the abdomen, it would not be possible or ethical to treat such a serious condition without knowing the cause. Doing a blood test to see the parasite under a microscope and assessing how much damage it has done is essential and it greatly affects the treatment and outcome. It lets us know whether there are any complications to the condition that we need to be treating at the same time, whether your pet needs a blood transfusion, or whether their immune system is coping. Blood tests are a vital part of our puzzle in trying to find out what illness your pet is suffering from, and how we can fix the condition as soon as posisble.
For senior pets we normally recommend yearly complete blood work. Many senior pets are on chronic medications and it is important to monitor their results and make sure they don’t experience subtle side effects that may go unnoticed on the outside.
By doing blood tests on an annual basis in older pets, it gives us a chance to pick up gradual or subtle changes that can lead us to detect disease early and save your pet’s life before they become clinically or critically ill.
Another reason to consider blood tests would be if your pet is receiving general anaesthetic. We perform what we call ‘pre-GA’ bloods (pre- general anaesthetic blood work). The results of the blood tests will give us an indication of your pet’s health and organ function and how well they will cope with full anaesthetic and if there are any precautions that we can take to support them during and after anaesthetic, or whether an anaesthetic should be avoided completely.
The normal wellness blood panel for an adult pet will include the evaluation of red and white blood cells (FBC/CBC: Full blood count/complete blood count), which reveals hydration status, anaemia, inflammation or infection.
Liver, kidney, and other organ functions, glucose levels, protein levels and occasionally electrolytes are all part of our basic chemistry blood panel.
Our patients can’t talk; they can’t explain their symptoms or what they are experiencing, so we have to look a little bit harder, reach a little deeper to find the problem and ensure they are healthy.