Veterinary advice should be sought from your local veterinarian before applying any treatment or vaccine. Not sure who to use? Look up veterinarians who specialize in poultry using our directory listing. Find me a Vet


Atherosclerosis is a common cardiovascular disease in birds, especially chickens. So frequently in fact (more so then in mammals), that an enormous amount of research has been done using domesticated birds such as quails, chickens, and pigeons as animal models for the disease in human medical research. Atherosclerosis is the leading cause of coronary heart disease and stroke in humans, and leads to 25% of all human deaths in the United States.

Atherosclerosis is caused by the accumulation of fatty substances, cholesterol, cellular waste products, calcium, and other substances (referred to as plaque) inside arteries. This plaque buildup will eventually obstruct blood flow, or travel to other parts of the body.

Chickens develop atherosclerosis from:
  • Consumption of a high-cholesterol diet, a diet low in polyunsaturated fatty acids (PUFA) and high in saturated fatty acids, or a high-fat diet enriched in linoleic acid.
  • Infection with the Marek's disease virus, which is known to cause atherosclerotic-like lesions in the arteries. It can also infect the smooth muscle cells, leading to accumulation of cholesterol in the arteries.

Signs of Atherosclerosis in Chickens

Atherosclerosis usually doesn't
Chickens won't usually develop any clinical signs of the disease until the advanced stages of the disease, when the artery is severely narrowed or completely blocked. Many times, the first indication of the disease is apparent sudden death related to an unknown cause.

When clinical signs do occur, they are usually associated cardiac failure caused by reduced blood flow through the arteries. Which may include lethargy, exercise intolerance, difficulty breathing, ataxia, and behavioral changes.

Clinical Signs

Exercise intolerance
Frequent fainting or collapsing
Difficulty breathing
Hind limb paresis
Sudden death


  • History
  • Radiographs
  • CBC
  • Necropsy


Change in dietSwitch to a low fat diet with supplemental omega 3 fatty acids
NiacinUsed to help lower total cholesterol.
HMG-CoA reductase inhibitorsRosuvastatin (Crestor), Pravastatin (Pravachol), Fluvastatin (Lescol), etc.
IsoxuprineA peripheral vasodilator that was used successfully in managing clinical signs in a parrot with presumed atherosclerosis.



  • Feed a low fat, low cholesterol diet with plenty of omega-3 fatty acids, particularly long chain EPA and DHA sources.
  • Vaccinate chicks for Marek's disease



Scientific References

Age Range

Usually seen in older birds.

Risk Factors

  • Unhealthy diet. Foods that are high in saturated and trans fats, cholesterol, sodium (salt), and sugar.
  • Infection with Marek's Disease virus (MDV) or Chlamydophila spp
  • Heavier breeds and/or obesity
  • Older age. As chickens get older, the risk for atherosclerosis increases.
  • Lack of physical activity
  • Stress