Livestock producers primarily, but policy makers also, have an interest in market effects from meatpacking plant closings and openings. This article presents results from a study to determine price impacts from an anticipated hog slaughtering plant opening and an unexpected fed cattle slaughtering plant closing. The estimated price effects for each plant event were modeled with price difference and partial adjustment models. The plant opening resulted in higher absolute and relative hog prices in the Provincial market where the plant was located. However, adverse price impacts from the fed cattle plant closing were less evident.