Getting Facilities Ready for the Next Crop of Calves
The dairy has a relatively new calf barn. It is set up with six bays with each bay holding a row of calves on each side and work alley in the middle. Each bay is mechanically ventilated with automatic controls for both inlet and exhaust air.
Each bay is run as an all-in, all-out facility. After the calves leave a bay is it is cleaned and sits empty for up to a week before being repopulated.
The past cleaning procedures include removing all the calf pens and feeding equipment, physically removing all the bedding and manure and pressure washing the walls and floor. The calf pens are pressure washed as well. Feeding equipment is scrubbed and allowed to dry.
I was asked to evaluate this cleaning protocol. While on-site I asked to look at the pressure washer. It is a cold-water unit. I know that high temperature high-pressure water will kill parasites (e.g., cryptosporidia, coccidia, giardia). So, my first recommendation was to switch from a cold-water to a high-temperature-water pressure washer - that is the kind with a boiler that delivers about 180F water. The idea is to cook the parasite eggs as well as wash away all kinds of pathogens.
I asked about the disinfectant that was used after a bay was cleaned. "Nope, we don't use a disinfectant," was the reply. They have available both Virkon-S and Tek-Trol from a local supplier. Both of these would be effective as a follow up to the pressure washing. I have been trying chlorine dioxide in the past year. Click Here for a resource on chlorine dioxide we are using at our vet clinic. The commercial product Oxine is available as well (http://www.bio-cide.com/).
The rationale for following up the pressure washing with a disinfectant is that no matter how carefully one pressure washes there are some residual pathogens that remain on walls and floors.
In summary, the idea is to get rid of manure - you cannot disinfect manure. Then, pressure wash to remove as much organic matter as practical. Then, disinfect as a final step to sweep up the "escapees." Letting the facility sit as long as possible before repopulating is a best management practice.