Numerous “agroterrorism” activities targeting animals have occurred in the past 100 years, especially during times of war. The first three examples mentioned below describe the use of biological agents (bacteria) during wartime conflict. The final example demonstrates an act of “domestic” terrorism targeted at a business inside the U.S. by a disgruntled contractor who worked within the system that he targeted.

Early in the 20th century, the German military attempted to use anthrax and glanders, two bacterial agents, to disable horses being used by Allied nations in World War I.

During the Kenyan war for independence against Great Britain, the MauMau forces used a plant-based toxin known as Kikuyu to sicken British cattle.

In Afghanistan, following the invasion by the Soviet Union in the early 1980s, the U.S.S.R. is alleged to have attempted to infect Afghani “freedom fighter” horses with glanders because the U.S.S.R. grew frustrated at their lack of progress following their invasion of Afghanistan.

A large-scale animal agroterrorism event happened in 1996 starting in the small town of Berlin, Wisconsin. Chlordane, an organochlorine pesticide, was intentionally added to animal carcasses taken to a rendering plant. The rendered materials were distributed to major animal feed producers. The tainted carcasses went into feed, which was distributed to over 4,000 farms, principally dairies.

The incident led to recalls of dairy products in four Midwestern states. It cost more than $4 million just to dispose of the products. Four thousand tons of feed and 500,000 pounds of contaminated fat were also disposed. Large-scale economic ripple effects were felt by the affected farms, local feed companies, processors and other people and business in the supply chain.

A competitor of the targeted facility was charged for this criminal contamination. Five months later, the same individual allegedly contaminated poultry feed with a fungicide. Wisconsin’s secretary of agriculture called this contamination an act of “domestic terrorism.”

Even though it wasn't an intentional event, the outbreak of Foot and Mouth Disease (FMD) in Britain in early 2001 illustrates what could happen if animals were targeted in an agroterrorism event. This FMD event cost over $18 billion, which included direct costs to the livestock industry as well as ripple effects to supporting industries. For example, tourism in rural areas of Great Britain ceased for several weeks after the initial outbreak.

Another issue of concern is the intentional infection of animals with one of the biological agents on the Center for Disease Control’s "Category A” list of bioterrorism agents. Many diseases on that list (for example, anthrax, viral hemorrhagic fevers, plague and tularemia) are significant threats to people as well as animals.