Improve your business by managing Fatty Liver Syndrome

Why is FLS a problem in breeders?

Even in well managed flocks, FLS occurs if there is a mismatch between energy intake and energy requirements.

  • If the energy intake is below requirement, the liver will start metabolising carbohydrates into fatty acids.
    These fatty acids need to be transported to the ovaries to support egg production, but if transport out of the liver cannot match the extra production, accumulation of fat in the liver leads to fatty liver disease.
  • If the energy intake is above requirement, the liver doesn’t have the capacity to metabolise the total amount of carbohydrates in the diet, which also leads to accumulation of fat in the liver leads to fatty liver disease.

FLS in breeders can occur at any stage during the laying cycle, with an increased risk at peak production and at the end of the laying cycle.

Diagnosing FLS in breeders

A drop in egg production in combination with an increase in mortality is suggestive of FLS, but the aforementioned signs can be observed as a result of many other problems. Inspection of the birds may sometimes reveal:

  • Pale combs
  • Sunken eyes
  • Increased amounts of fat covering the internal organs

A final diagnosis can be made by visual inspection of the liver. In some cases, it may be necessary to send liver samples to a lab for testing.


Download the necropsy guide

Once I have diagnosed FLS, how do I control it?

FLS is multifactorial; many different risk factors can play a role.

Example calculation of the potential impact of Fatty Liver Syndrome on farm economics

To calculate the economic impact of an outbreak of FLS in this example, a drop in laying percentage by 10% and an increase of mortality by 5% have been assumed. An outbreak of fatty liver syndrome typically results in these percentages. The economic impact per 1000 birds has been calculated.

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