Dairy cow health across an intensification gradient in Europe: an integrated multi-indicator assessment

Dairy farming systems in Europe range from low-input grazing systems to highly specialized indoor production systems, raising important questions about the relationship between production strategies, animal health and the sustainability of dairy production. While previous studies have generally focused on isolated health or production traits, this study provides an integrated multi-indicator assessment of dairy cow health across three farming systems representing a gradient of production intensification: low-input grazing systems, moderate-input grazing systems (GraCow), and fully indoor systems. Data were collected from dairy farms in France and Germany between 2018 and 2022 using herd-level performance indicators, clinical observations of animals, milk quality indicators and blood metabolites biomarkers. Low input farms were characterized by smaller herd sizes (40.7 Livestock Units vs. 197.4 and 608.8 LU; p < 0.001), lower milk yield per cow (4,573 vs. 9,531 and 9,965 kg/cow/year; p < 0.001), and greater breed diversity than GraCow and Indoor systems, which were composed almost exclusively of Holstein cows. Compared with the two other systems, cows from low input farms showed shorter calving intervals (391 vs. 416 and 413 days), lower lameness scores (1.04 vs. 1.48 and 1.86; p < 0.01), higher body condition scores during lactation (3.22 vs. 2.37 and 2.58; p < 0.01), and lower culling rates. Metabolic differences were also observed, including lower β-hydroxybutyrate concentrations in low-input systems (p = 0.02), although most biomarkers remained within physiological reference ranges. Because breed composition differed between systems, the potential contribution of genetic background to health resilience was considered when interpreting the results. Overall, this study highlights the value of integrating complementary indicators to better characterize dairy cow health and supports the potential role of lower-input grazing systems in sustainable dairy production.