Your Veterinarian may advise lab work for a number of reasons. There are various types of blood tests and they all vary in complexity, turn around time, and variety of organs or cells evaluated. Let’s take a look at each of these tests a little more closely to see why your vet may request these tests.

Why Your Veterinarian Wants Blood Work for Your Dog

by Dr. Eileen Savier CVA, CVCH

Your veterinarian may advise lab work for a number of reasons — Wellness Blood Screens, Heartworm Tests, Preanesthetic Blood Ccreens, Therapeutic (Routine) Drug Monitoring, or Illness Investigation. All of these panels vary in complexity, turn around time (time from submission until results are available), and variety of organs or cells evaluated. Let’s take a look at each of these tests a little more closely:

  • Wellness Blood Work is offered to healthy patients who are presenting for annual visits. They are used as baseline information to compare against if the patient becomes sick and also for early disease detection. This lab work is generally optional: I have pet parents who run this lab work yearly, others who elect to submit this every other year, and others who never run it. While it is completely up to you if you want to invest in this information, it is excellent information to have if your pet becomes ill.
  • Heart Worm Tests are also advised yearly (or every 6 months if you have missed doses of heart worm prevention or do not give prevention) this test is highly recommended even if you are religious about monthly parasite prevention. It may also be recommended if you are changing heart worm prevention products even if you haven’t missed doses to ensure that your pet is negative prior to starting a new prevention. This establishes a timeline if your pet is positive in the future.
  • Preanesthetic Blood Work is a smaller panel than the wellness screen and is run prior to surgical procedures. This gives us a small amount of information to help ensure there will not be complications with medications and surgery is safe to pursue.
  • Therapeutic (or Routine) Drug Monitoring is performed if your pet is on long term medication and the panel is dictated by the type of medication your pet is on.
  • Illness Investigation varies depending on the presenting signs, concurrent diseases, medications, or age. This may involve a CBC (complete blood count), Serum chemistry, Thyroid levels, Cortisol levels, and or urine and fecal samples. There are many other test that maybe advised depending on the results of the basic lab work tests.

Understanding Blood Tests for Dogs


The Complete Blood Count (CBC), helps your vet understand your dog’s hydration status, anemia, infection, blood clotting ability and immune system response. For dogs that have symptoms like fever, vomiting, diarrhea, weakness, pale gums or loss of appetite, a CBC may be essential. A CBC can also detect bleeding disorders or other unseen abnormalities which can be crucial if your pup needs surgery. Specifically, a Complete Blood Count provides detailed information including:

  • Hematocrit (HCT): measures the percentage of red blood cells to detect anemia and hydration
  • Hemoglobin and mean corpulscular hemoglobin concentration (Hb and MCHC): measures the oxygen-carrying pigments of red blood cells
  • White blood cell count (WBC): measures the body’s immune cells — increases or decreases in the WBC can indicate certain diseases or infections
  • Platelet count (PLT): measures cells that form blood clots
  • Granulocytes and lymphocytes/monocytes (GRANS and L/M): measures specific types of white blood cells
  • Eosinophils (EOS): measures a specific type of white blood cells that may indicate allergic or parasitic conditions
  • Reticulocytes (RETICS): measures the immature red blood cells — high levels indicate regenerative anemia
  • Fibrinogen (FIBR): provides important information about blood clotting — high levels may indicate a dog is 30 to 40 days pregnant


Serum Chemistry tests, or Blood Chemistries, are an evaluation of the major internal organs and is measured from the liquid portion of the blood. These tests evaluate your pup’s organ function, electrolyte status, hormone levels and more. These tests are important to evaluating the health of older dogs, dogs with signs of vomiting, diarrhea or toxin exposure, as well as dogs receiving long-term medications and general health before anesthesia. This panel can be simple or complex in the number of values reported but most panels include the following:

  • Albumin (ALB): a serum protein that helps evaluate hydration, hemorrhage and intestinal, liver and kidney disease
  • Alkaline phosphatase (ALKP): elevations in this test may indicate liver damage, Cushing’s disease or active bone growth in a young dog
  • Alanine aminotansferase (ALT): helps determine active liver damage, but does not indicate the cause
  • Amylase (AMYL): elevations in this test indicate pancreatitis or kidney disease
  • Aspartate aminotransferase (AST): increases in this test may indicate liver, heart or skeletal muscle damage
  • Blood urea nitrogen (BUN): determines kidney function — an increased level is called azotemia and can be caused by kidney, liver and heart disease as well as urethral obstruction, shock or dehydration
  • Calcium (Ca): changes in the normal level of this test can indicate a variety of diseases — tumors, hyperparathyroidism, kidney disease, and low albumin are just a few of the conditions that alter serum calcium
  • Cholesterol (CHOL): used to supplement diagnosis of hypothyroidism, liver disease, Cushing’s disease and diabetes mellitus
  • Chloride (Cl): Chloride is an electrolyte that is typically lost with symptoms like vomiting or illnesses such as Addison’s disease – elevations often indicate dehydration
  • Coristol (CORT): Cortisol is a hormone that is measured in tests for Cushing’s disease (the low-dose dexamethasone suppression test) and Addison’s disease (ACTH stimulation test)
  • Creatinine (CREA): reveals kidney function and helps distinguish between kidney and non-kidney causes of elevated BUN
  • Gamma Glutamy transferase (GGT): an enzyme that indicates liver disease or corticosteroid excess
  • Globulin (GLOB): a blood protein that often increases with chronic inflammation and certain disease states
  • Glucose (GLU): Glucose is a blood sugar — elevated levels may indicate diabetes mellitus; low levels can cause collapse, seizures or coma
  • Potassium (K): an electrolyte typically lost with symptoms such as vomiting, diarrhea or excessive urination — increased levels may indicate kidney failure, Addison’s disease, dehydration or urethral obstruction while high levels can lead to cardiac arrest
  • Lipase (LIP): an enzyme that may indicate pancreatitis
  • Sodium (Na): an electrolyte often lost with vomiting, diarrhea, kidney disease and Addison’s disease — this test helps indicate hydration status
  • Phosphorus (PHOS): elevations in this test are often associated with kidney disease, hyperthyroidism and bleeding disorders
  • Total bilirubin (TBIL): elevations in this test may indicate liver or hemolytic disease — this test helps identify bile duct problems and certain types of anemia
  • Total protein: indicates hydration status and provides additional information about the liver, kidneys and infectious diseases
  • Thyroxine (T4): Thyroxine is a thyroid hormone — decreased levels often signal hypothyroidism in dogs

About Dr. Eileen Savier

Dr. Eileen SavierBarks & Recreation is proud to feature Dr. Eileen Savier CVA, CVCH as our Veterinary Blogger in our “From the Vet” Series. Currently part of the team of doctors at Keystone Veterinary Clinic, Dr. Savier is a 2012 Graduate of the Ross University School of Veterinary Medicine, She completed her clinical experience at The Ohio State University and after veterinary school she pursued further education and certification in Veterinary Acupuncture, Chinese Herbal Medicine, and Fear Free veterinary visits. Dr. Savier has a special interest in integrative medicine, animal behavior, and internal medicine and is committed to improving animal health care by integrating Eastern and Western philosophies. She enjoys working with fearful & aggressive dogs and cats and she has had additional training in low stress handling techniques and encourages positive reinforcement during exams and procedures. Her clinical interests include pain management, animal behavior, geriatric patient care, and internal medicine. Dr. Savier is a member of the following associations:

Dr. Savier shares her home with two (soon to be three) dogs, two cats, and a toddler. She lovingly refers to her two dogs as Coconut Retrievers as they were rescue dogs she brought home from the island of St. Kitts. In her free time she enjoys spending time with her family, going to the beach, and planning her next Disney vacation.

Join us every month for Dr. Savier’s “From the Vet” series to get more information related to the health and welfare of your furry family members!

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