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Biochemical Profile in Cats

Also known as 'chemistry profile' a  biochemical profile is a series of tests your veterinarian may wish to perform to evaluate your cat's health.

Performed  on the clear/fluid portion of the blood. Biochemical profile tests a variety of bodily systems and can give an overall picture of how your cat's organs are functioning.

Some measure the amount of substances in the blood such as glucose, sodium, potassium, cholesterol, others measure the activity of enzymes such as aminotransferase (ALT), creatinine etc.

Normal values (conventional units):

Test SI Units Conventional (US Units)
Alanine aminotransferase (ALT) 5-130 u/L 5-130 u/L
Albumin (ALB) 24 - 41 g/L 2.4 - 4.1 g/dl
Alkaline phosphatase (ALP) 10-80 u/L 10-80 u/L
Amylase 500-1200 u/L 500-1200 u/L
Bilirubin-Total 0 - 6.84 u/L 0.0-0.5 mg/dL
Bilirubin-Direct 0 - 1.71 u/L 0.0 - 0.1 mg/dl
BUN 6.069 - 12.495 mmol/L 17 - 35 mg/dl
Calcium (CA) 1.875 - 2.7 mmol/L 7.5 - 10.8 mg/dl
Chloride 111 - 125 mmol/L 111 - 125 mEq/l
Cholesterol (CHOL) 1.092 - 4.42 mmol/L 42 - 170 mg/dl
Creatinine 70.72 - 159.12 µmol/L 0.8 - 1.8 mg/dl
Glucose 3.85 - 8.25 mmol/L 70 - 150 mg/dl
Magnesium 0.8-1.2 mmol/L 1.9-2.8 mg/dL
Phosphorous 1.0659 - 2.4225 mmol/L 3.3 - 7.5 mg/dl
Potassium 4.5 - 5.3 mmol/L 4.5 - 5.3 mEq/l
Sodium 147 - 156 mmol/L 147 - 156 mEq/l
T?   40-182 ng/dL
Total T?   1.0-4.8µg/dL

*these values will vary from laboratory to laboratory and hospital laboratory machines

Alanine aminotransferase (ALT) is an enzyme produced in the liver cells.  The ALT test determines the level of this enzyme in the blood, which increases when damage to the liver cells has occurred.

Albumin (ALB): The most abundant plasma protein, albumin  formed principally in the liver. It maintains osmotic pressure and as such is extremely important in regulating the exchange of water between the plasma and interstitial compartment (space between cells). Low levels of albumin in the blood can be a sign of liver disease.

Alkaline phosphatase (ALP) is a hydrolase (a group of enzymes which catalyses the hydrolysis of a compound) enzyme produced by the liver. It is present in high concentrations in the liver cells. It is elevated when there is acute damage to liver cells and sometimes with Cushing's disease.

Bilirubin: This is a major breakdown product of red blood cells. When red blood cells wear out they are trapped in the spleen and destroyed, releasing bilirubin into the blood. This type of bilirubin is called unconjugated. This bilirubin is transported in the blood to the liver, where it is taken up and conjugated (joined with glucuronic acid). This conjugated form may either be stored in the liver cells or excreted into the bile.  Bilirubin levels are increased in cats with liver disease, gallbladder disease or have an excessive destruction of  red blood cells (known as hemolysis).

Blood Urea Nitrogen (BUN): Urea nitrogen are waste products from the breakdown of protein. This is removed by the kidneys and excreted in the urine. High BUN values are indicative of dehydration and poor kidney function. Low BUN values can indicate liver disease.

Calcium (CA): Calcium is the most abundant  mineral found in the body, approximately 99% is found in bone and the remaining 1% in extracellular fluid (fluid found outside of the cells and between the cells in body tissues). It is essential for several functions including providing strength to bones and teeth, proper nerve impulses and muscle contractions, blood clotting. It is stored in the skeleton and released as it is required.  In combination with phosphorus, it forms calcium phosphate, the dense, hard material of bones and teeth. Hypocalcemia is too low a level of calcium in the blood and is a major clinical manifestation of hypoparathyroidism (a condition caused by the reduction or absence of secretions of the parathyroid gland), eclampsia (in lactating females), dietary insufficiency, antifreeze poisoning and Cushing's disease. High calcium levels can indicate cancer, hyperparathyroidism (a condition where the parathyroid gland produces too much parathyroid hormone), hypervitaminosis D (excess levels of Vitamin D), generally caused by over supplementation or rodenticide poisoning. [1]

Chloride: Chloride is an electrolyte. Its role is to help the body maintain a normal acid balance in the blood. High levels of chloride indicate dehydration, kidney disease, acidosis (low blood pH). Low levels indicate vomiting, diarrhea and metabolic alkalosis (loss of acid from the body).

Cholesterol (CHOL): Cholesterol is a fatty substance produced by the liver and found in all parts of the body. It is an essential component of body cells. It is a building block for certain hormones and is also used to build cell walls. Increased serum levels of cholesterol can indicate a major bile duct obstruction, hypothyroidism, Cushing's disease. Low levels may indicate liver disease.

Creatinine: Creatinine is a waste product of muscle activity found in muscle and blood. It is removed by the kidneys and excreted in the urine. High levels of creatinine are a sign of kidney disease or dehydration.

Glucose: Glucose is blood sugar that is a major source of energy for the body. High glucose levels can indicate Cushing's disease, Addison's disease, stress, diabetes. Low levels can be caused by liver disease, pancreatic tumour, insulin overdose, missed meals.

Magnesium (Mg): Magnesium is an essential blood salt necessary for nerve function, the activity of many enzymes, blood clotting, forming adenosine triphosphate (ATP) and production of insulin. Low levels can indicate poor kidney function, diabetes, and diarrhea.

Phosphorous: Phosphate is an abundant mineral in the body. Together, calcium and phosphate work closely to  build and repair bones and teeth. Around 85% of phosphate is found in the bones, the remaining 15% is stored in the cells where it is responsible for energy metabolism as well as being an integral structural component of DNA and RNA. Excess phosphate is filtered by the kidneys and excreted in the urine.  As the kidneys begin to fail, they are less able to get rid of excess phosphate, and levels begin to build up. Other causes of high phosphorous include Addison's disease and underactive parathyroid gland. Low levels may be caused by an overactive parathyroid gland, insulin overdose, dietary insufficiency, certain cancers.


Potassium is an essential electrolyte which performs several functions including;

  • Assists in regulating nerve impulse and muscle contractions

  • Helps maintain blood pressure

  • Maintains heart function

  • Maintains the body's electrolyte balance and acid/alkali levels in cells and tissues

  • It also plays an important  role in heart, skeletal, and smooth muscle contraction, making it an important nutrient for normal heart, digestive, and muscular function.

Most potassium is found in the body's cells. Cats obtain it through their diet. Kidneys control levels of potassium by excreting excess via the urine.

High potassium levels indicate acidosis, diabetes, acute kidney failure. Low levels (hypokalemia) may be caused by vomiting and diarrhea, dietary insufficiency.

Sodium: Sodium is an electrolyte necessary for the maintaining normal muscle function. Levels may be increased in dehydration. Low levels are found with Addison's disease.


[1] The Feline Patient - Gary D. Norsworthy, Mitchell A. Crystal, Sharon K. Fooshee, Larry P. Tilley.

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