Abstract :
The first part of this study was a cross-sectional analysis of the impact of 29 management factors on udder health in organic
dairy farms in Switzerland. All 77 farms joined the extension program ‘pro-Q’. As a measure of udder health the theoretical
bulk milk somatic cell count (TBMSCC) calculated by the monthly cow composite somatic cell count over a time period of
1 year was chosen. The basic udder health of the farms was determined by TBMSCC during the year prior to the start of the
project (mean for all farms5176 460 cells/ml). In the multivariable analysis, the five factors ‘swiss brown breed’, ‘alpine
summer pasturing’, ‘calf feeding with milk from mastitis diseased cows’, ‘hard bedding’ and ‘no post-milking’ remained as
significant risk factors on udder health. In the second part of the study, the development of management factors and the udder
health situation affected by an extension program after 1 year was investigated. A partial improvement of the management
factors on the farms but no overall improvement on udder health and no association between management changes and udder
health changes were found. Improvement of udder health was more likely in farms with higher basic TBMSCC than in those
farms with less udder health problems at the beginning of the project.
