A biosecurity plan is designed to prevent the introduction and spread of disease in a herd, or group of animals. External biosecurity includes practices directed at preventing the entry of new diseases into a herd. Internal biosecurity involves practices that aid in preventing the spread of disease within a group. A basic biosecurity plan in beef cow/calf operations should address risks associated with bringing in new animals, quarantine of new animals, communal grazing practices, and basic hygiene including cleaning and disinfection.

New Animals and Testing — The primary means of introducing new diseases into a herd is via introduction of new animals into the herd. National studies have shown that approximately 40% of beef producers imported cattle into their herds, yet rarely did the producers purchasing animals obtain any medical history from the source herds.