September 2021

 

Want to keep disease out of your calf barn? If so, it might be prudent to take a page from the biosecurity measures of our pig-and-poultry-raising kin, and set up a “Danish entry.”
(Taylor Leach)

 

It’s a concept that has been in use for years in poultry and swine facilities, and one that can offer the same biosecurity benefits to calf-raising facilities. The “Danish entry” system can help keep disease out by creating distinct sanitation zones which are separated by a bench.

Developed in Denmark, the Danish entry system originally was established to promote biosecurity in that country’s vast pork-production industry. Swine and poultry enterprises have adopted it worldwide, and the same concept also could help protect calves.

Kevin Janni, agricultural engineer with the University of Minnesota, said a Danish entry allows people to enter livestock barns in a relatively bio secure way, without having to shower in and shower out.

 

 

A standard, two-zone Danish entry, creates a “dirty” zone and a “clean” zone, divided by a bench that serves as a line of separation. As show in this video by the University of Minnesota, a person coming from the outside environment removes boots and coveralls in the “dirty” zone, sanitizes their hands, and swings his or her stocking feet over the bench to the “clean” zone.

In the “clean” zone, they dress in fresh boots and coveralls before entering the animal housing area. The procedure is reversed when they exit the building. The key is that dirty boots or clothing never cross from the dirty to the clean side. Ideally, a hand-washing sink and even a shower should be provided on the clean side.

Janni said a more elaborate, three-zone system provides an intermediate zone between the dirty and clean zones. This “gray” zone creates an additional buffer between the two sides, reducing the likelihood of contamination from one side to the other.

There are a number of detail options to a Danish entry system that can be customized to fit the farm. Some farms use trays of disinfectant to sanitize boots upon entering the dirty zone; others provide disposable, plastic covers that are placed over boots before entry. Signage that explains the process – possibly in more than one language – also is important.

Janni addresses these elements and more in this bulletin. The USDA’s Center for Food Security and Public Health also has published a detailed manual containing useful advice on Danish entries.

Canadian researchers cited a Danish bench system as a helpful tool to mitigate a severe outbreak of Salmonella Dublin in calves. A serious and highly contagious disease, S. Dublin often is shed via manure from older animals, readily spreading it to more vulnerable, young calves. Using a Danish entry to the calf barn can help limit exposure of young calves to this and other contagious diseases.

MAUREEN HANSON
Bovine Veterinarian