📊 Vet’s 2025 Guide to Lab Values for Dogs and Cats: What Bloodwork Really Tells You 🐶🐱

By Dr Duncan Houston, BVSc

Lab tests are one of the most important tools in veterinary medicine. 🧪 They help us peek inside your pet’s body—without surgery—by measuring enzymes, proteins, minerals, and other markers in blood or urine. 🩺

Whether your pet is sick or healthy, their bloodwork and urinalysis can tell us a lot. But these values can be confusing for pet parents. That’s why I’ve created this 2025 guide to explain lab values in plain language—with some helpful veterinary insights along the way. 🐾

📑 First Things First: No “One-Size-Fits-All” Numbers

Lab “normals” vary by:

• 🐾 Species (dog vs. cat)
• 🐶 Breed (e.g. Greyhounds vs. German Shepherds)
• 🎂 Age (puppy vs. senior)
• 💊 Medications and meals before testing

Important: Don’t panic if one number is bold or flagged—your vet interprets these values in context. A single “abnormal” doesn’t mean something is wrong. 🧠

🩸 Complete Blood Count (CBC)

The CBC gives us a snapshot of red blood cells, white blood cells, and platelets. Here's what each tells us:

• ❤️ Red Blood Cells (RBC): Carry oxygen. Low RBC = anemia.
• 🔬 White Blood Cells (WBC): Fight infections. High WBC = possible infection or inflammation.
• 🩸 Platelets: Help blood clot. Low = bleeding risk.
• 🌬️ Hemoglobin: The oxygen-carrying protein inside RBCs.

🧪 Common Biochemistry Values

✅ ALP (Alkaline Phosphatase)

🏥 Elevated in liver or bone disease—or from prednisone in dogs. Also rises with gallbladder issues in cats.

✅ ALT (Alanine Aminotransferase)

🧬 Enzyme from liver cells. High levels = liver injury or inflammation.

✅ Amylase & Lipase

🍭 Amylase breaks down sugar, lipase breaks down fats. 🔥 Both rise in pancreatitis or liver disease.

✅ Bile Acids

🍔 Measure how well the liver is processing fat—tested before and after a meal. Helpful in liver dysfunction diagnosis.

✅ Bilirubin

🧡 Waste product from old red cells. High = liver disease or red cell destruction. May cause jaundice (yellowing of gums or skin).

✅ BUN (Blood Urea Nitrogen)

💧 Kidney function marker. High = kidney disease or dehydration. Low = liver issues.

✅ Calcium

• ⬆️ High: Often linked to cancer or kidney disease.
• ⬇️ Low: Seen before birth (eclampsia), or from antifreeze poisoning.

✅ Cholesterol

🐾 Unlike people, dogs/cats rarely get heart disease from cholesterol. High levels may indicate diabetes, hypothyroidism, or kidney issues.

✅ Creatinine

💪 Comes from muscles. High = kidney dysfunction or dehydration.

✅ Creatinine Kinase (CK)

🏃 Muscle damage causes a rise—including heart muscle! May be elevated after injury, trauma, or seizures.

✅ GGT (Gamma-Glutamyl Transferase)

🔁 Liver enzyme. Increased with bile duct blockage, certain drugs, or gallbladder disease. High GGT + high ALP = likely liver issue.

✅ Glucose

• ⬆️ High: Diabetes or Cushing’s disease
• ⬇️ Low: Sepsis, insulinoma (pancreatic tumor), or starvation

✅ Phosphorus

⚠️ High in chronic kidney disease. Can also be influenced by diet or growth in young pets.

✅ Potassium

🩸 Monitored closely in kidney patients. High = acute kidney failure. Low = vomiting or diuretic use.

✅ Sodium

⬇️ Low levels are a hallmark of Addison’s disease. ⬆️ Slight elevation can come from dehydration.

✅ Albumin & Globulin (Total Protein)

🧪 Help us assess liver, kidneys, and inflammation. Albumin keeps fluid in blood vessels; globulins fight infection.

• ⬇️ Albumin: Liver failure, GI issues, hemorrhage
• ⬆️ Globulin: Infections, inflammation, cancers like lymphoma

✅ SDMA (Symmetric Dimethylarginine)

🧬 Early kidney function marker—more sensitive than creatinine. Detects kidney changes when 40% function is lost vs. 75% with creatinine.

🧪 Total Protein (TP)

🩸 Combines albumin + globulin. Elevated = dehydration or immune activity. Decreased = liver disease or protein loss.

🧴 Urinalysis (UA)

💦 This simple test gives clues about:

• 🚽 Urinary tract infections
• 💧 Hydration status
• 🍭 Sugar in urine = Diabetes
• 🔬 Protein in urine = Early kidney disease

Urine can be collected by free-catch, catheter, or cystocentesis (needle into bladder). It's quick, safe, and surprisingly revealing. 🧪🐾

🚨 When Lab Results Look Odd

Sometimes, a lab test shows a value out of range—but your pet seems 100% fine. In these cases:

• 🔁 Your vet may recheck in a few days
• 💊 Medications, diet, stress, or exercise could impact results
• 🧪 Lab error can happen (rare, but real)

Reminder: A healthy, happy pet always “outweighs” a single out-of-range number. Let your vet guide you. 🙌

📈 Don’t Interpret Alone—Ask A Vet

We know how overwhelming it is to see flagged results and medical jargon. That’s why AskAVet.com is here to help. 🧠💬

• 🩺 Upload test results for vet-reviewed explanations
• 📲 Chat with Dr Duncan Houston or our team for peace of mind
• 📅 Set recheck reminders for ongoing monitoring

📱 Download the Ask A Vet App

Need help decoding lab values or next steps after bloodwork? Our app puts veterinary insight at your fingertips. Get answers fast, from home. 🐕📲

🧠 Final Thoughts

Lab values are more than just numbers—they tell a story. When interpreted by your veterinarian, they help detect illness early, guide treatment, and track progress. 📖🐾

Let your vet be your partner in understanding what’s going on beneath the surface. And when you need help between appointments, remember: Ask A Vet is here for you. 💬❤️

Knowledge is power—and your pet deserves the best. 🐶🔬