However most will operate around 20-22% DM for a liquid feed mix which optimises ADG and FCR pretty much – some go as high as 25% DM plus, but above this physical pumping gets more problematic of course. Some also operate at lower DMs as in the so-called 'river systems' that were popular a few years ago. My guess therefore is that at about 22-23% FCR will be minimised (ie best) and outside this it will get worse.  What we also do know that FCR with wet feeding systems is usually about 0.1 – 0.2 units of FCR better than comparable dry feed systems.