Nope, didn't really need to train them, my first flock were adults(formerly free ranged) and after 2 weeks in the coop while I finished building the run they were ready for some fresh air and ground to scratch up into a dust bath. I opened the pop door and the cockbird lead them down the ramp, I probably used grains and some vocalizations tho.
It's close, a couple inches, but soon goes below the wall as you can see in pic.
Steepness, and number of cleats is important, they don't much like sliding when descending the ramp.
I feel that chickens often need to be coerced into doing what you want them to do by manipulating their environment and taking advantage of their instinctual curiosity....and 'hunger'.
If you want them to use the ramp, leave that door closed so they have no other choice but to use the ramp...then use the enticement of scratch grains or what ever treat that will make them overcome their fear of the 'new thing' with the desire to eat treats.
I add a 'training ramp' for chicks...sprinkling ramps with scratch grains was irresistible once they saw them there, took just a half a day for them to be scrambling up and down it.
Now the bigger ramp here is steeper than I usually recommend and the cleats are too far spaced also, but the scratch grains spurred them to overcome those aspects.
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