Thanks Suzy,
Yes, that is the kind of slats I was referring to. That would make a great pellet feeder. And from the picture, the openings appear to be about the same size as ours. I guess the difference is there is no place to go on the other side, so not much incentive to try to squeeze through. With ours, if they get through the openings, they are inside another "room."
Yesterday we hastily added a horizontal row of 2x4's and cut the openings down to just one foot high (by 8" wide), because I was afraid one would get stuck halfway through when we weren't there. Of course, if they try to go through now, they will definitely get stuck!
We had been using stock panels, but pairs of goats (even three, when they were smaller) would squeeze their heads into one square and almost get stuck, and some goats would choose openings too high and gag and cough while trying to reach down to eat pellets. Some of our goats are evidently not too bright. Feeding time wasn't pretty. So far this seems to work well.
Nancy