What does a refractometer measure in a blood sample?

A refractometer is an important tool in veterinary medicine that measures the total plasma protein concentration in a blood sample. This measurement is crucial for assessing the protein levels in the blood, which can indicate the overall health of an animal. The total plasma protein includes both albumin and globulins, which are essential for various bodily functions such as maintaining osmotic pressure, transporting substances, and immune responses.

When light passes through a blood sample on the refractometer, it bends at different angles depending on the concentration of solids in the liquid. The greater the concentration of proteins, the higher the refraction of light, allowing the refractometer to provide a reading of the total plasma protein levels.

This measurement is particularly useful for diagnosing conditions such as dehydration, liver disease, or infections that could alter protein levels in the blood. Understanding total plasma protein levels can aid in determining the animal's nutritional status and overall health condition.