Effect of lyophilization in sucrose plus dextran and rehydration in thioglycollate broth on performance of competitive exclusion cultures in broiler chicks.

Cecal bacteria grown under continuous-flow anaerobic conditions were lyophilized in skim milk (SM), Reagent 20 (R-20; sucrose and bovine serum albumin fraction V), or sucrose plus dextran (SDx), rehydrated in drinking water or thioglycollate-beef broth (TGB), and compared with fresh broth culture for control of Salmonella typhimurium enteric colonization in broiler chicks. All groups were challenged on Day 3 with 10(4) cfu of S. typhimurium per chick. Mean Salmonella colony-forming units in cecal contents of groups provided lyophilized cultures rehydrated in TGB were not different from those in groups provided fresh broth culture and were reduced (P < .05) compared with controls at 10 d of age. Likewise, groups treated with the cultured lyophilized in R-20 and SDx and rehydrated in TGB had fewer Salmonella than similar groups treated with culture rehydrated in water. The results of this study indicated that the culture was as effective when lyophilized in SDx as it was when lyophilized in SM or R-20; culture lyophilized in SDx, SM, or R-20 and rehydrated in TGB was more effective than when it was rehydrated in water for the reduction of Salmonella colonization in broiler chicks.