Prevalence of production disease related indicators in organic dairy herds in four European countries

The aim of this study was to assess the prevalence of production disease related indicators on 192 organic dairy farms in Germany, Spain, France and Sweden. The following indicators were used: raised somatic cell count (>100,000 cells/ml, subclinical mastitis), high fat/protein ratio (risk of ketosis), low milk fat (risk of acidosis), prolonged calving interval, clinical lameness, and mortalities of calves and cows. Prevalence of the assessed indicators varied widely between farms and countries. The median prevalence (interquartile range) were 51.3% (15.4) for subclinical mastitis, 10% (7.7) for risk of ketosis, 3.2% (4.7) for risk of acidosis, 42% (20.7) for prolonged calving interval, and 14.2% (20.4) for clinical lameness. The incidence risk of calves dying between 1 and 90 days of age was 0.002 (0.043) per month of risk. Cow mortality was 0.026 (0.048) per year at risk. The assessment has shown that a comprehensive set of indicators can be calculated from readily available data, sparing the need to establish new and costly procedures. Future research should focus on strategies for using the information most effectively to reduce the level of production diseases in organic dairy farms.