Use of a data-driven algorithm to guide selective dry-cow therapy

Abstract

Nationally in 2014, 80.3% of dairies applied blanket dry-cow therapy (BDCT) and 93% of cows were treated with dry-cow intramammary (IMM) antimicrobials. However, surveys indicate that >80% of dry quarters yield negative culture results. Selective dry-cow therapy (SDCT) describes the identification and treatment of only cows/quarters infected or at high risk for infection. The purpose of this study was to determine if a data-driven algorithm, without the use of culture, could identify and selectively treat only "high risk" cows (those likely benefitting from DCT) without adverse effects on animal health and production outcomes.