Pathology of Fatty Liver Hemorrhagic Syndrome in Layers

Fatty liver hemorrhagic syndrome (FLHS) is described as excessive fat in the liver associated with varying degrees of hemorrhage. The condition is almost universally confined to caged birds fed high-energy diets and is most often seen in summer months. The liver is usually enlarged, putty colored, and very friable, and it contains varying degrees of hemorrhage. The abdominal cavity often contains large amounts of oily fat. Affected birds may have pale combs, likely as a consequence of reduced egg production. The ovary is usually active, at least in the early stages, and the metabolic and physical stress associated with oviposition may be factors that induce the fatal hemorrhage.