Patent ID: 7225755

Claim:
A method of managing hogs in a hog plant as they grow from an initial weight to a final weight comprising: providing a series of separate pens within the hog plant from a first of the series through one or more intermediate pens of the series to a last of the series; dividing the hogs in the hog plant into the series of separate pens based generally on weight such that the lightest hogs closest to the initial weight are arranged in the first pen and the heaviest hogs closest to the final weight are arranged in the last pen; providing for each pen a respective sorting scale arranged to receive a hog therein and to weigh the hog located within the scale; the sorting scales having a plurality of outlet paths for the weighed hog which can be selected by the sorting scale, one of the paths leading to the next pen of the series or, in respect of the last pen, to a discharge location; arranging the sorting scales such that the hogs in the respective pen periodically enter and leave the sorting scale to be weighed therein; pre-determining a required number of hogs to be removed from the last of the pens, the required number being less than the total number of hogs in the last pen and less than the total number of hogs in each of the other pens of the series; and controlling the sorting scales of the series of pens to remove the required number of hogs from the last pen and to transfer from each pen to the next of the series a respective transfer number of hogs, which transfer numbers are substantially equal to the required number, so as to maintain the numbers of hogs in the pens substantially constant.