PB6 Supplementation in Weaned Holstein Steers During an Experimental Challenge.

To evaluate the effects of a patented probiotic, weaned Holstein steers, not shedding ( = 40; ∼90 kg), were supplemented (CLO) or not (CON) with CLOSTAT (13 g/hd per day; Kemin Industries, Des Moines, IA) in a starter ration for 35 d. The calves were assigned to one of four treatments in a 2 × 2 factorial design with CLO and CON calves that were orally administered (STM) or not (NoSTM). Calves were challenged with 1.