The truth about fatty liver disease?

[Brizi]

OTOH, there any many other studies finding FLH as a symptom in birds fed high fat diets, "high fat" being a relatively low fat ratio. Clinical presentations are more often associated with birds getting high fat or high carb diets - often both, which can make finding a root cause more difficult. Its a complicated pathology, with environmental, and a likely genetic component as well.

So, for a main diet, what would you think is a borderline dangerous amount of fat for chickens, on the low end and on the high end? It seems that most feeds contain 3%-4% fat, but I've seen as low as 1.5% and as high as 8%. It's kind of crazy how big of a swing there is.

 

[U_Stormcrow]

I just look for things around 2.5 percent to 5 percent, And recommend against the 8-10 percent stuff.

 

[Chris2018]

I saw some people discussing fatty liver disease on Facebook, and there was someone who claimed a few things that confused me. I'd like to know what you guys think.

1. More than 16% protein is bad unless the flock is molting.
2. Corn shouldn't be the first or second ingredient because it is high-energy.
3. Too many fatty treats are bad.

My thoughts:

1. I don't see how the amount of protein has much of anything to do with fatty liver disease. In fact, I thought 18-20% protein was the recommended level?
2. If a diet is balanced properly, why would corn as the first or second ingredient be a bad thing? What does being a high-energy ingredient even entail?
3. I totally understand how feeding too many fatty treat could be bad. However, how much fat would be too much fat in a main feed?

Quote from: Merck Manual Veterinary Manual.
Found Here

"Fatty liver hemorrhagic syndrome (FLHS) is a metabolic condition that affects chickens worldwide. Sudden death of birds in full production is the most common complaint. Key findings are excessive fat in the liver, associated with varying degrees of hemorrhage. The condition is associated with high-energy diets and restricted exercise. It occurs most often in warm, summer months. Fatty liver hemorrhagic syndrome is associated with a surfeit of energy intake, regardless of the source, in birds whose exercise is limited. Additionally, this condition is observed primarily in females. With the initiation of egg production, the estrogen levels in the serum increase, as does the fat content in the liver. FLHS can be induced experimentally in layers and even male birds by administration of estrogen. This suggests that FLHS occurs more frequently in high-producing birds that presumably are producing more estrogen from active ovaries."

To answer your first question,
Too much protein in a diet (more that the chicken needs) will get converted into fat just like with humans.
Now since a chicken eats to fill a caloric need (not because there "hungry"), a hen that is feed a low energy/ high protein feed could still get fatty liver especially if she is in a pen with little to no exercise.

Most commercially available feeds are balanced so that fatty liver doesn't happen. It isn't until people start over feeding table scrapes, adding stuff to their bagged feed thinking there making it better or more so when people try making their own chicken feed do you start seeing an imbalance.

As long as you're feeding a good feed, keep treats to a medium and give the plenty of room to exercise, you should not have any problems.

To answer your second question,
Corn is cheap, a good energy source, is the easiest grain for chickens to digest and is low in fiber.