Blood tests are one of the most important diagnostic tools your veterinarian uses to monitor your pet’s health. Collecting blood is quick, minimally invasive, and provides information about several body systems. Our Southern Arizona Veterinary Specialty and Emergency in-house laboratory provides results quickly, so our veterinarians can begin directing your pet’s treatment plan right away. For advanced testing, our specialists send blood samples to an outside laboratory to monitor your pet’s progress, chronic conditions, and medication effects. Blood work is a mainstay of veterinary care, and it can be helpful to understand which body systems the tests are evaluating and the meaning of the results. In this blog post, we review the basics of deciphering your pet’s blood work results.

Why do blood work on your pet?

Your pet’s blood test results provide your veterinarian with a lot of information about their health. Your veterinarian may order your pet’s blood work for many reasons, including:

  • Wellness — Annual or biannual blood tests establish your pet’s individual baseline, allowing your veterinarian to monitor changes over time.
  • Illness — Blood work provides important clues, and guides treatment decisions when your pet is sick.
  • Medication monitoring — Long-term medications can cause changes to organ and blood cell function that your veterinarian monitors periodically by analyzing your pet’s blood test results.
  • Chronic diseases — Many adverse health conditions change blood work results, and your veterinarian can use serial testing to monitor your pet’s progress during treatment.
  • Preanesthetic — Anesthesia requires healthy liver and kidney function, which is best assessed on blood work.

What is included in my pet’s blood work?

General blood work consists of two parts—the chemistry panel and the complete blood count (CBC). The chemistry panel analyzes enzymes and other substances in the liquid blood portion, and the CBC counts and characterizes blood cells. Together, these tests can help determine your pet’s organ function and hydration status, and whether infection or physiologic stress is occuring. Many specialized tests are available to diagnose specific conditions, but the CBC and chemistry panel give your veterinarian the baseline information they need for almost any situation.

How does your veterinarian interpret blood test results?

Every in-house blood machine and out-of-clinic laboratory have established reference ranges against which your pet’s results are compared. Values out of the reference range may indicate disease or dysfunction. Your veterinarian takes all variables into account, including breed, age, medications, and overall health status, to determine the meaning of your pet’s blood work results. 

What does my pet’s blood chemistry test evaluate?

A blood chemistry panel generally evaluates your pet’s organ function, and can help determine their hydration status. Important blood chemistry panel results include:

  • Kidney function —  Elevations in blood urea nitrogen (BUN) and creatinine (CREA) may indicate kidney disease, dehydration, or intestinal bleeding.
  • Liver function — Aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALKP), gamma glutamyl transferase (GGT), and total bilirubin (TBIL) measure liver function, but can also indicate dysfunction in other body systems.
  • Pancreatic function — Amylase (AMYL) and lipase (LIP) help detect pancreatic inflammation or cancers.
  • Glucose status — High glucose can indicate stress or diabetes, while low glucose can indicate a tumor.
  • Electrolyte status — Hormonal imbalances, dehydration, or kidney disease can cause problems with calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), and chloride (Cl). High or low electrolyte levels can cause serious heart or neurologic issues.

What does my pet’s CBC evaluate?

The CBC counts each blood cell type, and manual evaluation of a blood smear can determine if the cell structure is normal. Blood contains three cell components—red blood cells, white blood cells, and platelets. Red blood cells carry oxygen via hemoglobin, white blood cells fight infection and regulate immunity, and platelets play an important role in clotting. Your veterinarian uses blood cell counts and their ratios to determine:

  • Infection presence — When certain types of white cell levels are high or low, infection, stress, or cancer can be the cause.
  • Immune function — Low white blood cell levels can leave pets prone to serious infections.
  • Clotting status — Low or high platelet counts can indicate clotting or bleeding disorders.
  • Oxygen status — Low red blood cell levels (i.e., anemia) can impair oxygen transport.
  • Hydration level — The ratio of liquid blood volume to blood cell levels (i.e., hematocrit [HCT]) can signal dehydration.

Blood work is a key part of your pet’s overall health management, and can give your Southern Arizona Veterinary Specialty and Emergency veterinarian important clues about your pet’s health. If you have any questions about your pet’s blood work results, contact our team to discuss their care.