While outbreaks of dangerous contagious livestock diseases, such as foot-and-mouth disease, could be economically devastating to the U.S., other contagious diseases, such as salmonellosis, bovine viral diarrhea, Johne's disease, pseudorabies and porcine reproductive and respiratory syndrome virus, also are a threat.
The introduction of livestock is the single greatest threat for exposing a herd to contagious disease, but pathogens can be introduced other ways. For example, movement of birds and wildlife, feed and bedding, air- or water-borne particles, or farm visitors all can introduce disease.
Disease risk posed by visitors should be assessed critically. In some cases even a very small probability of disease transmission can have tremendous impact. Some operations can't accept any risk for contagious disease and strictly prohibit visitors.
These biosecurity principles can be used to minimize the risk:
- Some visitors pose a greater biosecurity risk than others. Visitors with recent exposure to livestock are more likely to carry pathogens. It's important to ask visitors if they have been on farms or had contact with other livestock. If in the U.S., some producers require 24 hours since contact with livestock.
- If in another country, require five days from visiting farms in a foreign country. Require clothes are laundered and shoes and personal items are cleaned thoroughly and wiped with a cloth dampened with a bleach solution (5 teaspoons of household bleach in 1 gallon of water).
- Require clean outerwear and boots. Visitors should wear clean clothing and have bathed since visiting another livestock facility. It may be prudent to provide clean coveralls, rubber or disposable boots and facilities to wash hands or shower.
- Minimize contacts. The closer visitors are to livestock, the greater the risk for transmission. Don't allow direct physical contact with livestock unless necessary. Also, visitors' pets should not be allowed near livestock facilities. Whenever possible, prevent vehicles that have been on other farms from entering livestock pens, feed alleys or feed preparation areas.
Dr. David Smith, UNL Extension dairy/beef veterinarian provided the information used in this week's column. For more information or assistance, please contact Allan Vyhnalek, Extension Educator, University of Nebraska-Lincoln, Extension in Platte County. Phone: 402-563-4901 or e-mail AVYHNALEK2@unl.edu .
