They range from everyday practices, such as the routine cleaning and disinfection of materials and facilities, to national policies regarding disease eradication and surveillance.
Biosecurity has been described as having three major components: isolation, traffic control and sanitation.
As an operation’s biosecurity plan needs to be tailored to the individual needs of the operation, this article will focus on sanitation in the form of disinfectants for facilities, as well as vehicle and trailer biosecurity.
Disinfectants for facilities
There are multiple disinfectants commercially available, and each one is unique in its properties and designations.
Different classes include chemicals such as alcohols, aldehydes, biguanides (an example being chlorhexidine), halogen-based agents (examples being bleach and betadine), peroxygen compounds (an example being hydrogen peroxide) and quaternary ammonium compounds.
It is important to realize they are not all the same, and many different factors can contribute to their efficacy.
A good starting point in selecting a disinfectant is to consider what the goals are for the product. Is this for routine cleaning of a truck, trailer or chute? Or is this for an area that recently housed a sick calf
Next, evaluating the label of the disinfectant is important. From a practical standpoint, a disinfectant that is not labeled as effective probably will not work on a ranch.
A reference for selecting disinfectants is available at the Disinfectant Database at the National Biosecurity Resource Center.
This database allows the user to search disinfectants by name, manufacturer, class and also by the agent of concern.
For example, if there is an outbreak of calf scours attributable to E. coli that required treatment of multiple animals, a rancher can go to the page, select “E. coli” under the “Disease/Pathogen” class and get a selection of multiple disinfectants that could be further investigated for use in cleaning pens, hutches, chutes and equipment that came into contact with calves.
When evaluating the label of a disinfectant, it is important to evaluate factors such as safety (toxicity, handling), the surface to be disinfected (concrete, wood, painted), dilution (amount of water, time) and contact time required, as well as the water available (temperature, pH, “hardness”), as these factors could have an effect on the overall goal of disinfection.
These factors are key to consider, as painted concrete surfaces are easier to disinfect than bare wooden surfaces due to the smoothness of the surface and decreased likelihood of debris sticking.
Not all disinfectants require the same volume of water for dilution, and some have a recommended expiration date after they are diluted.
Hard water can be problematic as the minerals in hard water can form curds with some disinfectants, not allowing them to work properly.
By picking an appropriate disinfectant and utilizing it in the intended manner, facility sanitation can be used as an important component of a biosecurity plan.
Vehicle biosecurity
Trucks, trailers and other vehicles are an essential component of any agricultural operation, and the risks associated with these need to be considered in an operation’s biosecurity plan.
Decontamination of employees’ vehicles, trailers, commodity trucks, rendering trucks, merchant vehicles and construction equipment should be evaluated on a regular basis as part of an operation’s biosecurity plan.
Vehicles present a challenge for cleaning because they consist of varied materials, irregular surfaces and potentially damaged surfaces, as well as harboring many hard-to-access areas.
Vehicle disinfection should only be performed if the temperature is above 50ºF. This is to prevent water from freezing and allowing disinfectants such as aldehydes and certain acids to function unimpaired, as they can have decreased efficacy below this temperature.
A commercial truck wash is an excellent site for vehicle disinfection because of the enclosure, as well as the ability to clean the underside of the vehicle.
A preliminary rinse can remove up to 90 percent of the contamination if the water temperature is between 100 and 114ºF.
When rinsing a vehicle or trailer for disinfection, the potential for aerosolizing pathogens should be considered. If using a pressure washer, it may be appropriate to spray with a disinfectant rather than water alone to limit the potential spread of pathogens via aerosolization.
Detergents can also be utilized to aid in the removal of fats and proteinaceous material, as well as minerals. Detergents should be utilized at their specific temperatures and contact time to ensure stability and efficacy.
A final rinse should then be utilized to prevent redeposition of contaminants on the surface being cleaned. A partial list of truck washes is recorded at the Truck Wash listing at the National Biosecurity Resource Center, also available at the Purdue site.
This list allows the user to select a state and find listed commercial truck washes, as well as the water available, and if they will allow a livestock trailer. It is important to note that not all commercial truck washes will allow the cleaning of the interior of a trailer. Some may only allow for exterior cleaning.
As with cleaning, disinfecting a vehicle can also prove to be challenging. Care needs to be taken to ensure that the manufacturer recommended dilution and contact time is followed.
Hand-brushing disinfectants and soapy water are preferable to pressure-washer spraying for disinfection, as a pressure washer can release contaminated aerosols. For this reason, a disinfectant should be used with water if a pressure washer must be used.
The properties of the disinfectant also need to be considered, as application method, dilution and contact time will all vary amongst disinfectants.
When undergoing regular vehicle cleaning and disinfection, regulations (EPA, OSHA, local, etc.) may need to be investigated.
An example of regulation is the EPA’s recommendation that companies or individuals take their vehicles to a car wash that has a National Pollutant Discharge Elimination System permit.
If this is not available, it is recommended to wash a vehicle over a grassy area so waste water is absorbed into the ground instead of running into a street or storm drain.
The purpose of these regulations is to prevent the waste water from entering an underground water body or public water source.
Vehicle biosecurity can be a component of a biosecurity plan that allows for decreased disease transmission among operations.
To prevent introduction from other operations, designated parking or vehicle areas could be used to limit contact with cattle. Similarly, signage in the form of “no trespassing” signs can be used to limit vehicle traffic to only those vehicles authorized to be on the premises.
Conclusions
While there are many facets to biosecurity for cattle operations, and these will vary from operation to operation, incorporating sanitation practices for facilities and vehicles will aid in disease control and biosecurity measures.
Other practices, such as records and written protocols for sanitation that are displayed for all employees to see, will also aid utilization of disinfection and biosecurity. 
Joe Smith
Resident Veterinarian
UC Davis Veterinary Medical Teaching Hospital
