I have lost numerous chickens to impacted gizzard. We have done a necropsy each time to confirm this. One time it was impacted with fibers from those flower planters that are like straw. Another time it was 100% grass impaction. The other time it was pieces of glass in the gizzard. It's hard enough losing chickens that I didn't want to lose. So now I am lead to wonder, can impacted gizzard be prevented? Can it be treated once it has occurred? As for prevention, I have heard that you must keep your lawn mowed short, so that they are not ingesting long strands of grass. This is not an option for us because our sheep doing the mowing and it is not short at all times. To combat this, what I do is feed them first thing in the morning their layers crumble and wait until they fill up on that before letting them outside for the day to free range. This way, they are not overly hungry and hopefully will not gorge themselves on grass first. I also provide grit and oyster shells, free choice, in a hopper. But they don't seem to take much out of it. So maybe I need to sprinkle grit into their feeder? As for treatment, I'm wondering if giving vegetable oil would soften it up like it does for crops? Maybe that would be useless? All I know is the one that had her gizzard impacted with all grass, the gizzard was hard as a rock and I doubt oil could have done it. Any one have any thoughts, knowledge, experience on gizzard impaction?