* Relative risk reduction (RRR) calculations based on an aggregate analysis of 11 studies. BRD RRR = 53.6% (95% Confidence Interval = 45.1–62.2%); with a 28-day observation period. Chronics/mortalities RRR = 72.6% (95% Confidence Interval = 54.7–90.5%); with a 28-day observation period. Pfizer Animal Health. Technical Bulletin Nos. DRX05019, DRX05020, DRX05021, DRX07033, New York: Pfizer Animal Health, 2005–2007