Association of herd productivity and bulk-tank somatic cell counts in US dairy herds in 1996

Abstract

Objective - To assess the association of bulk-tank somatic cell counts (BTSCC) and the value of herd productivity (milk produced, calves born, and net costs for cow replacements) in US dairy herds in 1996. Design - Randomized stratified national survey of dairy producers. Sample Population - Records from 1,219 dairy herds in the top 20 dairy states. Procedure - Responses for 1,178 herds had complete information for economic analysis. Per-cow value of production was determined for each herd. Data for herds with high (≥ 400,000 cells/ml) and medium (200,000 to 399,999 cells/ml) BTSCC were compared with values for herds with low BTSCC (< 200,000 cells/ml), using a multivariable regression model. Results - In 1996, milk was priced at $0.287/kg ($13/cwt). Herds with low BTSCC annually generated $103.90/cow more in herd productivity than herds with medium BTSCC and $292.39/cow more than herds with high BTSCC. Conclusions and Clinical Relevance - Increased BTSCC (> 200,000 cells/ml) were associated with a reduced value of productivity per cow. Thus, dairy producers have a financial incentive to seek out and implement cost-effective management practices that will enable them to decrease their BTSCC to < 200,000 cells/ml and maximize herd productivity. (J Am Vet Med Assoc 2001;218:1325-1330).