Page 106 - SpeedhorseMarch2021

VETERINARY VIEWS
bacteria are attacked with disinfectants. The only way to remove all pathogens is through the process of sterilization, which is not appli- cable to a stable environment.
Put on protective clothing, eye and respira- tory gear before saturating all surfaces with the selected germicide. Apply disinfectant at the manufacturer’s specified concentration; extra water dilutes it with potential loss of effective- ness. Hard water can also reduce the effective- ness of some disinfectants. Directed misting application is useful for disinfecting areas that can’t be cleaned directly with water, such as overhead lighting and electrical conduits.
Besides disinfection of barn surfaces, equipment such as waterers, mangers, feed buckets, blanket racks, horse toys, and cleaning equipment like rakes, shovels, and wheelbarrows also need attention. Prior to disinfecting the barn, remove these items
to clear obstructions to the cleaning and disinfecting process. Attend to these items separately – clean and rinse thoroughly. Then,
place them in the sun to dry – ultraviolet also has germicidal effects. Tractors, horse trailers, tires, mats, mangers, mud guards and trailer ramps should also be cleaned and disinfected as these also harbor microorganisms that can be carried around the property.
The longer that disinfectant contacts the surfaces, the better. Contact times vary with the disinfectant, concentrations, and envi- ronmental conditions – check manufactur-
ers’ labels. While a general guideline is 10-15 minutes, it could take longer in colder ambient temperatures. If attempting to control an infectious disease outbreak, you may want to reapply another layer of disinfectant once the first layer has dried.
DISINFECTING OTHER AREAS OF THE FARM
When it comes to disinfecting paddocks and fences, it is hard to disinfect rough and porous surfaces, such as wooden fence rails; the amount of fencing that has to be disinfected is
often prohibitive. Sunlight is a good disinfec- tant for these areas, killing most pathogens fairly quickly, especially if dry. Dirt cannot
be disinfected but turning over surfaces to help maximize sun contact is helpful. It is most important to pay attention to horse-to- horse contact as well as common fomites (an inanimate object that transfers pathogens) and vectors such as tack, peoples’ hands and cloth- ing, and barn equipment.
Water tanks and vessels need to be disinfected; water is a known vehicle for transmission of many diseases, includ- ing strangles (Streptococcus equi). Drain the tanks, scrub to remove debris, apply a disinfectant for the required contact time, and then rinse thoroughly to remove any disinfectant residue. The same procedure is applied to feeders, especially those used communally amongst horses.
Insect control is important to limit spread of infection especially from body secretions, such as wound drainage.
Check manufacturers’ label directions for important safety information with respect to chemical application and compatibility with other products intended for use, and regarding safety requirements for humans and horses.
Because disinfectants work best on “pre-cleaned” surfaces, it is essential that as much visible organic debris is removed as possible.
Thorough cleaning may eliminate 90% of bacterial content while another 6-7% of bacteria are attacked with disinfectants.
Once all surfaces are clean and rinsed well, remove excess water from walls and floors with a squeegee, and allow them to dry.
104 SPEEDHORSE March 2021