Fatty liver hemorrhagic syndrome

Fatty liver hemorrhagic syndrome (also referred to as fatty liver syndrome), a disease in chickens and other birds, affects only hens (females).[1] Birds with this disease have large amounts of fat deposited in their liver and abdomen.[2] This often results in an enlarged liver that is easily damaged and prone to bleeding.[3] In some cases the disease is fatal, usually as a result of blood loss from an internal hemorrhage in the liver.[1] The hemorrhage often occurs when a hen is straining to lay her egg.[3] Fatty liver hemorrhagic syndrome is "the major cause of mortality in laying hens." [4]

Causes

Excessive dietary energy intake is believed to be the cause of fatty liver hemorrhagic syndrome.[3] Heredity may also play a role, but it is not the entire cause for the disease.[1] Birds housed in cages will more likely be affected because they are unable to exercise to burn off the extra dietary energy.[3] Walking hens are less likely to develop this problem. The disease is observed most often in birds that appear to be healthy and in a state of high egg production.[3] As a result, death can occur quite unexpectedly.

Symptoms

Affected birds are usually overweight and may also have pale combs.[2] Generally, however, the disease has few or no symptoms prior to the bird's death.[5]

Treatment

The use of L-Tryptophan in the diet can decrease the syndrome.[6]

References

  1. 1.0 1.1 1.2 "Miscellaneous Management Related Diseases," Cooperative Extension Service: Mississippi State University. Retrieved from Msstate.edu on 2007-03-11.
  2. 2.0 2.1 "Fatty Liver Syndrome: Introduction," Merck Veterinary Manual Online, 8th Edition, 2003. Retrieved from Merckvetmanual.com on 2007-03-10.
  3. 3.0 3.1 3.2 3.3 3.4 "Poultry: Causes for Fatty Liver Hemorrhagic Syndrome," Mississippi State University Extension Service. Retrieved from Msucares.com on 2007-03-11.
  4. Cherian, G, "Fatty Liver Hemorrhagic Syndrome in Laying Hens: An Investigation into the Role of Dietary Fatty Acids," USDA Current Research Information System (CRIS).
  5. "Death Occurring In Fowl," GameRooster.Com Disease Diagnostics Aid. Retrieved from Gamerooster.com on 2007-03-11.
  6. Y. Akiba et al, L-Tryptophan alleviates fatty liver and modifies hepatic microsomal mixed function oxidase in laying hens, 1992, Comp. Biochem. Physiol. Vol 102A, N°4, pp 769-774.