Understanding Blood Tests for Cats

Introduction to Why Are Blood Tests Important for Cats?

When you take your cat to the doctor, they may recommend blood tests to monitor your pet’s health. These tests help to accurately detect underlying conditions that might not be visible yet. Whether it’s for routine check-ups or due to suspicious signs of illness, blood tests can quickly reveal a lot about your cat’s health. Blood tests are crucial in identifying causes of discomfort or illness in your pet, and they serve as a valuable guide in deciding the next steps for medical care. As a cat owner and someone familiar with how important these tests are, I can tell you firsthand that they play a significant role in making care recommendations that help ensure your pet lives a long, healthy life. For example, a blood test can show how well your cat is responding to medical treatments and track the progress of their recovery. It’s an effective way to manage chronic conditions and adjust treatments to suit your pet’s evolving health needs.

Why is a CBC Important for Your Cat?

A CBC is an essential test that provides a wealth of information about your cat’s overall health. It helps the doctor assess several key factors such as your cat’s hydration status, ability to fight infection, and the immune system‘s response. If your cat is showing signs like fever, vomiting, diarrhea, weakness, pale gums, or loss of appetite, a CBC can be crucial in identifying abnormalities like anemia or hidden infections that may not be immediately obvious. In my experience, this test is often recommended when a cat is feeling unwell or has symptoms that point to an underlying issue that requires closer examination.

A CBC also provides valuable insights into your cat’s blood clotting ability and whether they might have a bleeding disorder—important before any surgery or treatment. If there are any abnormalities, the results guide the doctor on how to respond and provide the best care for your pet. It’s an effective way to catch unseen issues early, ensuring that you can address any problems before they become serious.

• HCT/PCV : The hematocrit or packed cell volume (PCV) test measures the percentage of red blood cells in your cat’s blood. It’s an essential test to detect anemia, dehydration, or issues that might be caused by bleeding episodes. If your cat is feeling weak, tired, or has pale gums, this test can help the doctor figure out if your pet’s red blood cell count is normal or if there’s an underlying problem that needs attention. While common in dogs, the HCT/PCV is crucial in understanding your cat’s health, as it provides insights into their blood health and overall well-being.
• HGB and MCHC The hemoglobin (HGB) and mean corpuscular hemoglobin concentration (MCHC) tests are crucial for understanding your cat’s red blood cells and their ability to carry oxygen. Hemoglobin is the pigment in red blood cells that helps transport oxygen throughout your cat’s body, while MCHC measures the concentration of hemoglobin within those cells. Low levels of either can indicate problems like anemia or insufficient oxygen supply to tissues. From my experience, these tests are key in diagnosing conditions that affect your cat’s energy levels and overall health, helping the doctor make accurate decisions on how to proceed with care.
• RETICS Reticulocytes are immature red blood cells that have not fully matured yet. A test measuring reticulocytes can help the doctor understand how your cat’s body is responding to recent bleeding or if it’s dealing with regenerative anemia. If the reticulocyte count is high, it usually means that your cat’s bone marrow is actively producing new red blood cells to replace lost ones. When there are high levels, it often indicates that the body is trying to repair itself from blood loss or another issue affecting red blood cell production. From my experience, this test is valuable for assessing whether your cat’s anemia is regenerative, meaning the body is still able to respond to the problem.
• WBD The white blood cell count (WBD) is a crucial test that measures the number of infection fighting cells in your cat’s blood. These white blood cells play a key role in the body’s immune system, protecting it from various diseases. If the WBD is increased, it often signals that your cat’s body is fighting an infection, while decreased levels might indicate issues like cancer, leukemia, or a weakened immune system. In my experience, a white blood cell count can provide vital clues to the doctor about your pet’s health, helping to identify whether your cat has an underlying infection or a more serious condition affecting the immune system.
• NEU, LYM, MONO The NEU, LYM, and MONO are specific types of white blood cells that each play an important role in your cat’s ability to fight infection. Neutrophils (NEU) are the first line of defense, working hard to fight bacterial infections. Lymphocytes (LYM) help fight viral infections and can be elevated in cases of chronic infections or cancer. Monocytes (MONO) assist in fighting more serious infections and clean up damaged tissues. If any of these cell types are elevated, it can indicate an active infection or potentially a more serious health issue like cancer. Based on my experience, analyzing these cell types in a blood test gives a more detailed look at what’s going on inside your pet’s immune system, helping your doctor make the right treatment decisions.
• EOS Eosinophils are a specific type of white blood cells that help your cat’s body fight allergic reactions and parasitic conditions. When these cells are elevated, it can indicate an ongoing allergic response or an infection caused by parasites like worms. In my experience, if a cat is showing symptoms like itching, vomiting, or weight loss, a high eosinophil count might suggest an allergic reaction or parasitic infestation that needs to be addressed. This test provides valuable insight into whether your cat is dealing with such conditions, helping the doctor pinpoint the right treatment.
• PLT The platelet count (PLT) test measures the number of cells in your cat’s blood that are responsible for helping form blood clots. These platelets play a key role in controlling bleeding, so a low platelet count might mean your cat could have trouble stopping bleeding, while a high count could indicate an underlying condition like an infection or bone marrow problem. In my experience, a PLT test is crucial if your cat has had recent bleeding issues or is showing signs of bruising easily, as it helps the doctor understand whether your cat’s blood is clotting properly.

Blood Chemistry 

Blood chemistry tests are common blood serum tests that evaluate your cat’s overall health by checking things like organ function, electrolyte status, and hormone levels. These tests are important for evaluating the health of older pets, ill pets, or cats on long-term medications, as they give insight into the function of vital organs such as the kidneys, liver, and heart. From personal experience, these tests are often used before procedures involving sedation or anesthesia to ensure your cat’s organs can handle the stress. Additionally, regular screening with blood chemistry tests is a great way to monitor your pet’s health status and catch any underlying issues early.

• ALB  The ALB test measures the level of albumin, a serum protein that plays a crucial role in maintaining your cat’s hydration and overall health. This test is important for evaluating potential issues like hemorrhage, intestinal problems, and liver or kidney disease. In my experience, if the albumin levels are too low, it could suggest that your cat’s organs are not functioning properly, which is why this test is often part of the diagnostic process for sick cats. Monitoring albumin levels helps veterinarians understand your pet’s health status and guide treatment.
• ALKP The ALKP test measures alkaline phosphatase, an enzyme that can indicate potential liver damage in cats. Elevations in ALKP can signal liver issues or conditions like Cushing’s disease. In younger pets, slightly higher ALKP levels may be due to active bone growth, which is generally normal. However, in older pets, a significant elevation could suggest more serious health concerns. In my experience, if a cat has slight elevation of ALKP, it’s often monitored over time to see if it resolves or requires further investigation, ensuring your pet’s well-being is closely checked.
• ALT The ALT test measures alanine aminotransferase, which is a sensitive indicator of active liver damage in cats. If this enzyme level is high, it can point to liver issues, but it doesn’t indicate the cause. In my experience, a slight elevation of ALT in pets is often normal, especially in younger animals. However, in older pets, elevated ALT levels may suggest a need for closer observation, as it could signal more significant liver concerns. Regular monitoring can help ensure early detection of any issues and keep your pet’s health on track.
• AMYL The AMYL test measures amylase, an enzyme that helps break down starches in the body. Elevated levels of amylase can sometimes point to pancreatitis, an inflammation of the pancreas, or kidney disease. From my experience, elevations in amylase are not always definitive on their own, as they can be influenced by different health conditions. It’s important to assess the test results alongside other clinical signs and tests to get a complete picture of your cat’s health.
• BUN  (blood urea nitrogen) test is a useful way to evaluate kidney function in cats. Increased BUN levels may indicate kidney disease or even other conditions like liver disease, heart disease, or urethral obstruction. In some cases, it can also be caused by shock or dehydration, as these factors affect how well the kidneys filter waste. I’ve seen elevated BUN levels in cats with azotemia, a condition where waste products build up in the blood, signaling the need for further investigation.
• CA The calcium levels in a cat’s blood are important indicators of their overall health. Deviations in calcium can point to a variety of diseases or conditions. Tumors or hyperparathyroidism can cause elevated calcium levels, while kidney disease or low albumin can lower it. These changes in serum calcium are critical in identifying underlying health issues, as they can significantly alter the body’s functions. In my experience, it’s always essential to pay attention to abnormal calcium levels, as they often lead to further tests for a clearer diagnosis.
• CHOL Cholesterol levels in a cat’s blood can provide valuable insights into their health. Elevated cholesterol can be a sign of several conditions, including hypothyroidism, liver disease, or Cushing’s disease. It’s also seen in cats with diabetes mellitus. While sometimes an increase in cholesterol might be linked to a supplement or diet, it’s important to have these levels tested for a more accurate diagnosis. In my experience, when cholesterol levels are off, it often leads to further testing to identify the root cause of the problem.
• CREA Creatinine is an important indicator used to assess a cat’s kidney function. When a cat’s creatinine levels are elevated, it often suggests kidney issues, but this test can also help distinguish between kidney and non-kidney related causes of health problems. It works alongside tests like BUN to provide a more complete picture of the cat’s health. From my experience, high creatinine levels typically indicate a need for further tests to confirm the extent of kidney damage or other underlying issues.
• GLOB Globulin is a type of blood protein that plays a role in immune function. When levels of globulin increase, it can often indicate chronic inflammation or certain disease states affecting your cat. From my experience, elevated globulin levels can be a sign of ongoing infections, autoimmune diseases, or other health concerns. This test helps vets understand the severity of the situation and guide treatment decisions.
• GLU Glucose, or blood sugar, is an important part of a cat’s blood test, as it can indicate several health issues. Elevated levels of glucose may point to diabetes mellitus, a condition where the body can’t regulate blood sugar properly. On the other hand, low levels of glucose can be very serious and lead to symptoms like collapse, seizures, or even coma. In cats, the blood glucose level is typically under 250, while in dogs, it’s under 180. As a pet owner, it’s essential to monitor glucose levels, especially if your cat shows signs of being nervous or lethargic.
• K Potassium is  crucial electrolyte that helps maintain proper cell function and muscle activity in cats. When there are signs like vomiting, diarrhea, or excessive urination, it could be a signal of potassium imbalances. Increased levels of potassium can indicate serious issues like kidney failure, Addison’s disease, or dehydration. On the other hand, if potassium levels are excessively high, it could lead to dangerous conditions such as cardiac arrest or urethral obstruction, both of which require immediate medical attention. Keeping track of potassium levels is essential for diagnosing and managing these health problems.
• AML Amylase is an enzyme found in the blood that helps break down carbohydrates. Elevated amylase levels can indicate issues such as infection or inflammation in the body, particularly in the pancreas. In cats, like in dogs, high amylase levels may suggest conditions like pancreatitis, which is inflammation of the pancreas. Monitoring amylase is important to help diagnose and manage such conditions, especially when symptoms like abdominal pain or vomiting are present.
• Na Sodium is an essential electrolyte in the body that helps maintain the balance of fluids and proper nerve function. Abnormal sodium levels can indicate several health issues in cats, such as vomiting, diarrhea, or more serious conditions like kidney disease or Addison’s disease. Low or high sodium levels can also reflect the cat’s hydration status, helping veterinarians determine if the cat is dehydrated or retaining too much fluid. Proper sodium levels are crucial for the overall health of your cat, so any significant changes can be a warning sign of underlying issues.
• PHOS Phosphorus is an important mineral in the body that plays a key role in bone health and energy production. In cats, elevations in phosphorus levels can signal problems like kidney disease or hyperthyroidism. In some cases, high phosphorus levels may also point to bleeding disorders. For young cats or kittens, phosphorus levels might be elevated due to active bone growth, which is normal, but any significant changes in older cats should be monitored closely. Keeping an eye on phosphorus levels through blood tests can help detect potential health issues early on.
• TBIL Total bilirubin is a substance produced when red blood cells break down. When blood tests show elevations in bilirubin levels, it can be a sign of liver problems or blood hemolytic disease. For example, high bilirubin might indicate issues with the bile duct, such as blockages or infections. It can also point to anemia, where the body isn’t producing enough healthy red blood cells. A bilirubin test is useful to identify these potential health issues, helping veterinarians spot certain types of conditions that could affect your cat’s well-being.
• TP A total protein test measures the amount of proteins like albumin and globulins in your cat’s blood. It can provide important clues about your pet’s hydration status and liver or kidney health. Low levels of total protein might suggest liver issues or kidney disease, while high levels can be linked to infectious diseases or inflammation. This test can also offer additional information to help indicate potential health problems, giving your veterinarian a clearer picture of your pet’s condition.
• T4 The T4 test measures the level of thyroxine, a crucial thyroid hormone in your cat’s blood. Decreased levels of T4 may signal hypothyroidism, a condition where the thyroid doesn’t produce enough hormone, leading to sluggishness or weight gain. On the other hand, high levels of T4 could indicate hyperthyroidism, a common issue in older cats that can cause weight loss, increased appetite, and hyperactivity. This test is important to indicate if there is a thyroid problem affecting your cat’s health, much like it is used in dogs for similar issues.

What is lab work for a cat, and how is it done? 

Lab work for a cat typically involves taking a blood sample to run blood work and check for any underlying health issues. The blood is often drawn from veins in the jugular vein in the neck or from the front leg vein or back leg vein. A small gauge needle is used to minimize discomfort. This sample is then analyzed by analyzers to measure different substances in the blood, comparing them with normal values to spot any signs of disease. Sometimes, a urine sample is also collected, often by retrieving it from the bladder using a special method, such as using cat litter to help. These tests give a full picture of your cat’s health and help the vet identify potential health concerns.

How does a baseline lab test impact the health and wellbeing of your cat?

A baseline lab test is an important step in understanding your cat’s health. It provides a foundation for future health assessments and allows the vet to track any changes over time. By doing a blood work test early, it helps in spotting any potential problems before they become serious. If something occurred or is indicated by the test, the vet can take action quickly. It also provides a timeline for comparison each year, showing if your cat’s health remains normal or if any issues need addressing, ultimately ensuring your pet lives a longer, healthier life.

What specific things are being looked at using my cat’s blood work, and what health conditions can they help detect? 

When your cat’s blood work is done, the vet will examine several key aspects of their health. The CBC (Complete Blood Count) looks at the number of red blood cells, white blood cells, and platelets. These numbers can reveal issues like anemia or infections. Blood chemistry tests assess kidney function, liver function, protein levels, and pancreatic function, helping detect conditions like kidney failure, liver failure, or diabetes. Thyroid levels are also checked, as abnormalities can point to thyroid disease.

In addition, a urinalysis is often included, which looks for bacteria, urine crystals, casts, and blood cells. This helps identify urinary infections, kidney disease, or even calcium deficiencies or excesses. Electrolytes like sodium and potassium are measured as well to monitor your cat’s hydration status. The tests can also check for viruses such as the feline immunodeficiency virus or feline leukemia virus. All of these tests work together to provide a full picture of your cat’s health and help identify any underlying issues early.

FAQ’s

What does a full blood test show in a cat? 

A full blood test for a cat, often called a CBC (Complete Blood Count), measures important components like red blood cells (RBCs), white blood cells (WBCs), and platelets. This helps detect issues such as anemia, infection, or even dehydration. A low RBC count could indicate anemia, while an elevated WBC count may signal an infection. Platelet levels are also checked to see if there’s any problem with blood clotting. The results provide valuable insights into your cat’s overall health and help your vet identify any conditions that need attention.

What does high mcv mean in cats? 

From years of working closely with veterinarians, I’ve often seen pet owners worry when they hear that their cat has a high MCV on a blood test. MCV, short for mean corpuscular volume, shows the average size of your cat’s red blood cells. When this number goes up, it usually means the red cells are larger than normal. This isn’t a disease itself but can point to other problems, like vitamin deficiencies, especially B12 or folate. Sometimes, even if iron deficiency is not the main issue, it’s worth checking for it too, especially since low MCV usually signals that instead. Understanding these values helps vets figure out what’s happening inside your cat’s body—something I’ve learned can be life-saving if caught early.

What is a normal blood count for a cat? 

When I first started helping at a clinic, I learned how important it is to understand hematology, or what vets call the complete blood count, in cats. This test gives a full picture of your cat’s health by checking levels like PCV, which should fall between 30–45%, showing how much of the blood is made up of cells. Hgb, or hemoglobin, is another key value, normally ranging from 9.8–15.4 g/dL, and it helps carry oxygen. The RBCs, or red blood cells, should be between 5.0–10.0 × 10⁶/mcL, and when your cat’s making new blood cells, the reticulocytes should stay within 0–0.6%. These numbers might seem confusing at first, but knowing these reference ranges really helps track early signs of illness and guide proper treatment.

What is a Chem 10 blood test for cats?

In my experience working with aging pets or those on ongoing treatment, the Chem 10 is one of the most helpful lab test tools we use to check their inner health. This test measures important chemistry levels in the blood, such as kidney function, liver function, blood sugar, and protein levels, which can all change over time or due to medications like NSAIDs, phenobarbital, prednisone, or even thyroid supplements. For cats taking these regularly, I always recommend doing this panel twice-yearly to spot problems early, even before symptoms show up. It gives a clear picture of how well the body is working, helping us adjust meds or decide on further steps quickly and safely.