Complement 3 Deficiency in Dogs

Category: Immune System
Breeds documented: 1
Published sources: 6

Overview

A missing immune protein called C3 weakens part of the body's defense against infection. C3 belongs to the complement system, a group of proteins that helps the immune system fight invading germs. Dogs with this inherited deficiency can develop repeated bacterial infections, particularly in the skin and lungs. The effects vary, because other immune pathways can sometimes help compensate for the missing protein.

Signs to watch for

Repeated skin infections
Coughing during associated lung infections
Low energy or poor appetite during associated lung infections
Difficult breathing during associated lung infections

The protein deficiency is present from birth.

Emergency Go to an emergency vet now if your dog has difficulty breathing.

Diagnosis and tests

Diagnosis uses a blood test to measure the amount of C3 protein. A low result supports a deficiency of this part of the immune system. The vet also considers the pattern of infections and the dog's history when investigating an inherited immune problem.

Breeds with documented risk

1 breed

By breed size

1 Medium

BrittanyMedium · Sporting Group

Inheritance

Not yet known
None of the sources we use states how this is inherited in dogs yet.

We've gathered what published sources say about this condition, so you can talk it through with your vet. It isn't veterinary advice: you and your vet know your dog best.