Lighting of Milking Parlours: Results from a Field Study

The aim of the study was to investigate the lighting of milking parlours at pit and milking stall levels. The field study was carried out in ten milking parlours with natural light inlets on the sides. The average illuminance (Ea) of the milking pit and milking stalls was calculated according to the CIBSE method. The measurements occurred on July 2018 before and during the afternoon milking session using a lux meter for assessing the impact of the operator and the animals on the illuminance of milking stalls. A k-means cluster analysis was performed using the JMP 15.2 software (SAS, Cary, NC, USA). Clustering analysis divided the milking parlours into three groups. Groups 1 (n = 5) and 2 (n = 3) included herringbone milking parlours respectively with less and more than 12 milking stalls. Group 3 included two parallel milking parlours with 40 milking stalls. On average in all groups of milking parlours the lighting power density (LPD) was below the recommended 6.0 W/m2. The light fixtures were positioned over the milker’s pit and the cow stances respectively at 2.3–3.3 m height above the pit floor and at 1.4–2.4 m height above the milking stall floor. Only Group 3 showed Ea values at milking stall before and during milking above that recommended by the reference technical standards (Ea > 200 lx).