It came as a real shock(震惊) to find out that chickens could tell what color they were eating.
I picked up a package of mixed greens one day. I anxiously brought it home and immediately took a trip out to the chicken house to deliver(递送) it. I knew the girls would welcome the treat!
My chickens have their regular gravity-type feeder for their grain(谷物), and I have a large plastic dog dish that I use for those special treats.
I emptied the bag of greens into the dog dish and stood back, as I usually do, to watch for a minute. I began to notice that the chickens were eating the green lettuce(莴苣)but were leaving the red leaves. I though it must be mistaken, but I didn't have time to find out for sure right then.
When I went back a short time later, the dish was empty except for the red leaves. The chickens didn't eat them with the red leaves. It took several hours, but they finally did eat it. I guess if they had their druthers(偏爱), they'd choose for green leaves only. Red leaves only satisfy in the absence of greens.