I have seen a feedlot, with a similar setup. They have a watering 'trough' where the animals drink. After they are familiar with it, they put dividers down, where only one calf at a time can easily drink. One or two of these, have a scale, and an electronic tag reader. Whenever a calf gets a drink, its weight is automatically recorded. Over time, their computer can chart their weight gains for each animal. I don't think they have a scale in every one of these 'stalls', so I assume either the calves drink out of the ones with the scales often enough to get a weight, or else they block off the others from time to time to get them to drink from the ones that do. Last I knew, this was sitll an 'experiment' with no patents or anything on it, and it wasn't a very well kept secret, as our local Young Farmers group took a tour through there, where I saw it.
