Globulin Levels in Dogs

Veterinarians will usually recommend a complete blood screen and chemistry panel for dogs prior to surgery and or for those animals showing symptoms of disease. These tests check organ function as well as show how the electrolytes and individual blood components are working. In particular, tests for levels of blood proteins (including globulins) can indicate serious diseases of the liver and immune systems.

Function

Globulins make up 38 percent of the proteins in the dog's blood; the other 62 percent is composed of albumen that maintains fluid pressure and fibrinogen, a clotting protein. Synthesized by the dog's white blood cells, globulins can be separated into five functional groups that work to provide immunity from disease. These include carrier proteins, which transport specific substances; phase reactants, that are involved in the inflammatory process; clotting factors; complement components, that combine with the antigen-antibody process; and the gamma globulins, also called immunoglobulins. Immunoglobulins may occur naturally in the dog's serum but are usually produced as a reaction to a particular antigen (a substance that produces an immune response). Individual immunoglobulins will combine with whatever antigen elicited their production and can be found in other body fluids and organs as well as blood--namely urine, spinal fluid, spleen and lymph nodes.

Features

Different types of immunoglobulins perform different functions in the dog's body.

IgA immunoglobulin works mainly as an antiviral defense against infections that enter through the mucous membranes of the dog's body. IgE immunoglobulin releases histamine and serotonin in the body to react against allergies. It is present in dogs with seasonal and skin allergies and gastroenteritis. IgG is the main immunoglobulin present in colostrum (mother's milk) and, as such, provides the puppy's first defense against disease. IgM immunoglobulin is the dog's defense against most infectious disease, such as distemper and parvovirus. It also reacts against the toxins of diphtheria, tetanus, botulism and snake venom.

Diagnostic Values

In a healthy dog, normal total protein levels should be 5.5 to 7.5 g/dL (grams per deciliter). This combines both the albumin and globulin levels. Normal albumin values should read 2.6 to 4.0 g/dL, while healthy globulin levels should be 2.1 to 3.7 g/dL.

Significance

An increase in value of total proteins in the dog's blood indicates certain physiological conditions including dehydration and cancers of the bone marrow and blood. A decrease of these values may be associated with malnutrition, internal bleeding and liver and kidney disease. Low globulin levels indicate some type of immune system disorder, including infections and immune-mediated disease. Higher globulin values are seen with stress, dehydration, blood diseases, liver disease, heart disease, allergies, diabetes and arthritis.

Treatment

Veterinarians will use these blood values to help discern diseases in the canine patient. After diagnosis, the vet will normally treat the primary disease, using medications and various therapies to combat the condition and its symptoms. Veterinarians will commonly continue to check the animal's blood proteins during the course of treatment to determine the extent of the illness and whether the treatment is working.