Bulk somatic cell count (BSCC)âthe number of white blood cells per milliliter of bulk milkâis one of the most powerful welfare indicators in dairy farming. High BSCC reflects udder inflammation (mastitis), indicating that cows are experiencing pain and immune system activation. Monitoring BSCC trends is therefore central to both welfare assessment and herd health management.
BSCC below 200,000 cells/ml is generally indicative of a herd with low mastitis prevalence. BSCC above 400,000 suggests significant subclinical mastitis in multiple cows. Subclinical mastitisâmastitis without obvious visible signsâis insidious precisely because cows suffer without obvious signals to observers. Somatic cell count is the best available proxy for this hidden suffering.
Research using behavioral and physiological pain biomarkers confirms that mastitisâincluding subclinical mastitisâis painful. Cows with mastitis show reduced lying time, altered gait, and suppressed appetite. Appropriate analgesia (pain relief) is a welfare standard that many farms still fail to meet consistently.
Modern dairy operations monitor both bulk tank BSCC (herd-level) and individual cow BSCC through monthly milk recording. Individual cow data identifies chronic subclinical cases, new infections, and treatment response. Trend analysisâwatching for seasonal rises or sudden jumpsâenables proactive management rather than reactive crisis response.
EU and UK regulations set a legal maximum of 400,000 cells/ml for bulk milk. Industry welfare assurance schemes like Red Tractor set lower targets. Research suggests welfare-optimal BSCC is below 150,000 cells/ml at herd level.
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