Free-stall cleanliness is affected by stall design

The objective of this study was to describe free-stall design and free-stall contamination in a cross sectional field study and to evaluate the effect of free-stall design on free-stall cleanliness. Five trained observers recorded cleanliness and use of bedding in 7 different sectors in 15 random selected free-stalls in each of 232 dairy herds. Of these, 8 herds were excluded from the statistical analyses due to stalls recently being cleaned out despite instructions not to do so. The observers also recorded the position of head and neck rails as well as stall width and construction of a possible brisket locator. The free-stall base was divided into seven sectors and the cleanliness of each sector was scored using a five grade scale reflecting the degree of contamination of each section. Two types of contamination were registered; faeces fallen on stall base (FAECES) and wet footprints (FOOT). Mean stall base length was 2.39 (± 0.21) m when placed against wall and 2.23 (±0.11) m in a double row. Mean height of the neck rail was 1.07 (±0.05) m, upper head rail 0.90 (±0.15) m and lower head rail 0.37 (±0.18) m. Contamination was mainly observed in the three rear sectors of the stalls. The most important factors in improving stall cleanliness on the basis of FAECES, in ranked order, were found to be: amount of bedding > 1.0 L, diagonal stall length ≤ 1.96 m, absence of lower head rail, stall length < 2.30 m, brisket locator distance ≤ 1.83 m, stall width > 1.13 m and upper head rail >0.70 m. Regarding FOOT contamination, the most important preventive factors were, in ranked order: amount of bedding >0.5 L, soft stall base with >0.5 L of bedding, brisket locator height ≤ 0.10 m, upper head rail >1.0 m, concrete stall base and stall width ≤ 1.13 m.