I do remember reading that study last year or so.  I think the definition of losses in actual field usage is maybe different than in a research study. That study was also done on concrete if I recall.  I guess I'm running my own study - I use 4 different types of hay feeders.

Yes there does appear to be more hay under a cradle at the end of day 1 - however if you make them empty it they eat the hay below the feeder since it has not been trampled or crapped on. When there are calves around they eat what's underneath.  And the bales are not sitting on the ground.

I have a Bextra which is somewhat like a cone feeder and it probably "loses" less than any of my others. However calves can't reach the center and can't push it around and would starve if I didn't come out and jiggle the bale with a spear or move the feeder with the loader about half way thru a bale.  It is also a pain to load with large heavy bales without bending it.

I have a couple different 8' round rings with slant bars that sit on the ground and they are useful except there ends up being a significant portion of the bale sitting on the ground and at times of the year is not useable.  The lighter rings can be pushed around enough so the calves can get to it.

It is also difficult to refill a regular ring or the Bextra when it still has a partial bale in it. Cone feeders in general also just don't hold enough for my application. If I was around to tweak, jiggle and fill every day maybe I would feel differently.

Back to the cradles: they are heavy duty, up off the ground, easy to load, hold 2 big bales which will be almost 100% available and I can put a couple new bales on top when there are still partial bales in them...Any size cattle can get to all of the hay in them. What falls eventually and usually gets eaten.

I guess in my climate I am also not real interested in any feeder with a floor in it since they seem to fill up with wet, inedible crud and need to be emptied.

So on balance I think the cradles have a lot going for them as primary winter feeders. I think there is also a place for a simple lightweight standard old steel ring such as the two-piece Applegate I referenced above. Especially this winter where I currently have 4 different separate groups. I have a very heavy duty ring but actually like the lighter Applegates as easier to move. They are low enough cost they dont need to last forever but are nicely made.

I think there is a reason there are so many different hay feeder designs on the market. Again no one answer to everyone's needs.  There is also much more to the choice than just the "losses" measured on concrete in a study. As I recall the "cradle" feeder in the study was actually a very different design from the ones I use pictured in the link above. jmho.

Jim at Dawn