What Is Fatty Liver Hemorrhagic Syndrome?
Fatty Liver Hemorrhagic Syndrome (FLHS) is an unfortunately very common non-infectious disease that causes fatalities in chickens with few outward symptoms in the time leading up to their unexpected death. Although it is most associated with hens who are used in egg production (especially those confined to cages), it has also been known to affect chickens in non-commercial settings. Because estrogen plays a large role in the disease, FLHS is unusual in male birds. The disease is very similar to the human ailment known as nonalcoholic fatty liver disease.
The disease causes an afflicted bird’s liver to gradually accumulate fat, killing their liver cells and replacing the functioning liver with scar tissue. Their liver grows and becomes more fragile to a point where it either can no longer properly function, or the liver ruptures, and the bird dies as a result of internal bleeding. Sometimes the rupture is associated with the stress of laying an egg with an enlarged liver.
The disease is most likely to cause death in the summertime months, possibly due to the added stress of heat and reduced inclination to exercise.
What Causes FLHS?
Due to the way that birds remove lipids from their liver (by using a form of protein), those who have a protein or specific amino acid deficiency end up accumulating excess lipids in their liver.
It has been found that FLHS is caused by a number of possible concurrent variables, including the following:
- A genetic predisposition to the disease
- Stress from heat, especially in the summertime
- Reduced exercise and obesity
- Egg-laying (increased estrogen from laying leads to higher rates of the disease)
- Excessive high carbohydrate foods (such as scratch or corn)
- Excessive high fat foods (such as black oil sunflower seeds)
- Generally, a low-protein high-fat diet (protein less than 17.5% and fat greater than 3.5%)
- A Biotin, Choline Chloride, Copper, or Vitamin E deficiency
- Tainted or moldy food
- Increased age increases the risk of the disease
- Metabolic disease (such as a thyroid dysfunction) is associated with increased risk
- Both Mycoplasma Gallinarum infections and vaccinations are associated with increased risk
What Are The Symptoms Of FLHS?
Although it is quite difficult to discern that a bird is suffering from FLHS, there are some indicators of the disease, including:
- A pale comb (in a non-implanted hen; implanted hens have pale combs)
- Comb dandruff
- Greenish diarrhea or yellow droppings
- A quick drop in egg-laying in a non-implanted hen
- Lethargy or a refusal to move as much as they used to
- Difficulty breathing
- An enlarged or distended abdomen
- Excess fat in the bird’s abdomen
- A more “fluffed up” appearance than usual
- Brittle eggshells due to worsened calcium metabolism
How Can FLHS Likelihood Be Reduced?
Generally, the best prevention for FLHS comes with adjustments to diet, exercise, living spaces, and reproductive care, including:
- Providing heat relief in the summertime
- Increased exercise and incentivized movement
- Food restriction as necessary to control a bird’s weight
- A high protein, low fat diet
- A lower carbohydrate diet (such as wheat or barley)
- 6% oat hull supplementation in their diet
- Adding organic selenium, ethoxyquin, Vitamin E, Vitamin B12, Choline chloride, and Inositol (cantaloupe is a good source) into a bird’s diet
- Providing fewer high calorie or high fat treats
- Providing fresh fruits and vegetables in a bird’s diet
- Supplementation of dandelion, alfalfa meal, and milk thistle may be able to help an FLHS-afflicted bird
- Implanting egg-laying chickens, potentially
If You Suspect A Chicken Has FLHS
If you are at all concerned that a bird under your care may be developing FLHS or is at all under the weather, it’s important to contact a veterinarian as soon as possible. Never assume a bird will get better if something seems amiss. Birds hide illness as a defense mechanism, and once they become symptomatic, their ailments tend to be in advanced stages. Speaking up can save a life.
If you have to wait for a scheduled veterinary consultation, quarantine them and give them a cooler space with easy access to some food and water.
Fatty Liver Haemorrhagic Syndrome | Diseases Of Poultry (Non-Compassionate Source)
Backyard Poultry Medicine and Surgery: A Guide for Veterinary Practitioners (Non-Compassionate Source)
Low Protein And High-Energy Diet… | Oxford Academic (Non-Compassionate Source)