Fed up of this, we decided to invest in a new British-made treadle feeder but alas, the only one we could find has now had a plastic lid and plastic tread plate fitted! A huge number of the positive reviews mentioned that the wire grid prevents the food from flowing properly and they warn to check the feed level and push feed down with your hand if needed.

After installing and the 3-4 weeks of training I noticed I was using about 10-15% less feed every month. For the first week of training, two bolts prop the lid open fully and the birds get a feel for standing on the plate and putting their heads into the trough to eat.

Since having it rats have eaten their way into the stable where I keep the chooks and now know the food is there, and the hens poop all over it. As soon as I attempted to have even a slight movement introduced it was as if the end of the world had come. The standard feeder that was used in this test holds 9Kg which is a little under half a sack of feed and can feed half a dozen chickens for 10 days. There is a larger version available that can hold twice as much as well though if you have a large flock. It took several years for Bill (Grandpa) Kirkham, a retired farmer to perfect his automatic chicken feeder.

They work on a simple idea: A rat weighs around 300g, wild birds such as crows even less and the lid of the feeder will only open with a weight greater than about 500g so a chicken can open the feeder to eat but the others cannot!I followed the training plan and all five of my girls picked it up in the 3 weeks without any problems. At first, I found the chickens were pecking at the lid and I would partially hold the lid open for them until one stepped onto the treadle plate as you’ll see in the photo gallery (my hand is holding it slightly open if you look bottom right) but I found out after observation that my rather large birds could comfortably stand back and reach over the top of the treadle plate to the feed without having to stand on it, so it took mine a little longer than most to get the hang of it. As for the OP's question, about the only way to ant proof anything is to borrow a trick that was used back in the day; adding some sort of moat with oil.