http://blogs.desmoinesregister.com/dmr/index.php/2010/07/23/fed-cattle-up-5-percent-in-iowa/ ~ they have feed lots where they use troughs to both feed and water thousands of cattle at a time.
Sorry I didn’t see your post earlier..
But a feed lot preparing for slaughter is far different than a rancher fattening the herd for the slaughter.
The cattle in the feed lot are there for a short period of time. Raising cattle is another story.