VSD/VSD+ (ventilation shutdown) is an inhumane method of agriculture animal depopulation in which both natural and mechanical ventilation of air is stopped so that the temperature inside the animal housing facility is raised to deadly levels with or without the addition of steam, CO2, or heated air.

The animals die of hyperthermia, heat stroke, and/or suffocation. This process can take HOURS, in which the entire time these animals are in SEVERE DISTRESS and pain. 

This method is approved by the AVMA as a means of mass depopulation as a "last resort" in the following circumstances: severe pathologic and zoonotic disease, urgent threat to food safety, radiological exposure (handling is a danger to workers), and natural disasters in which the animals cannot be moved or taken care of to prevent unnecessary suffering.

It was never meant to be used as a COST-SAVING METHOD due to COVID19 caused economic distress. 

The AVMA cites studies (Smith, Crabtree, Bird 2008) that show pigs may remain alive up to 16 hours after VSD and experimental studies showing chickens live an average 3.75 hours. VSD+ (added use of CO2 and extra heat) guidelines state that 100% of the animals must die within the HOUR. 

The general public is wholly unaware of these methods.

We urge the AVMA to classify Ventilation Shutdown (VSD and VSD+) as “Not recommended” in the AVMA Guidelines for the Depopulation of Animals: 2019 Edition.