Does the preparation of chicken liver mousse require force feeding of chickens?
There's no need to force-feed the chickens.
Chicken Liver Mousse is just a posh word for a smooth paté, with sometimes a bit of extra aeration.
For every chicken, there's a chicken liver. The world eats a lot of chicken these days, so there's a lot of chicken liver to spare. All you need to add is butter for the extra fat content &amp; resulting mouth-feel.
At its simplest, it's chicken liver, lightly sautéed in butter &amp;/or oil, added onion or garlic, herbs &amp; spices, alcohol, cream etc to taste, then whizzed in a blender until perfectly smooth. It's often not really a mousse, as it's not really fully aerated, but extra aeration makes it tend further towards an actual mousse, which the cooling butter will attempt to hold in place. You could go further perhaps using gelatine etc to hold the mousse as it cools.