One to two thirds of the floor is covered with litter (Fig. 1).
Figure 1. Deep litter system with manure pit for laying hen / floor housing (UBA, 2019, according to European Commission, 2017, modified)
The other part of the area consists of an elevated and perforated floor. The difference in height between the perforated floor and the littered area is a maximum of 50 cm. Below the slatted floor there is an 80-90 cm deep manure pit. The removal of manure is done regularly with manure scrapers (Fig. 2) or manure belts (Fig. 3) installed in the manure pit.
Figure 2. A manure scraper in cattle housing
Figure 3. Manure belt underneath caged hen housing
Manure is then stored in covered tanks/units to minimise ammonia losses to the air.