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. It is caused by the accumulation of fatty substances such as cholesterol, cellular waste products, and calcium (referred to as plaque) inside arteries. The buildup of plaque results in the obstruction of blood flow, and will travel to other parts of the body.

Chickens can develop atherosclerosis from any one or combination of the following:
  • Poor Diet: 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.
  • Viral induced: 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

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

When clinical signs do occur, they are usually associated with 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)
IsoxsuprineA 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)
  • Heavier breeds and/or obesity
  • Older age. As chickens get older, the risk for atherosclerosis increases.