TREATMENT OF COMMERCIAL BROILER-CHICKENS WITH A CHARACTERIZED CULTURE OF CECAL BACTERIA TO REDUCE SALMONELLAE COLONIZATION

The effect of treatment with a newly developed characterized continuous-flow (CCF) culture composed of 29 strains of cecal bacteria on salmonellae colonization was evaluated in commercially reared broiler chickens. Newly hatched chicks in three flocks were sprayed with CCF culture as they were placed in rearing houses and compared with untreated flocks on the same farm. Hatchery transport tray liners and rearing house feed, water, and litter samples were cultured for the presence of salmonellae. Cecal samples were cultured after 3- and 6-wk growout. Skin-feather samples were cultured at 6-wk growout. Fifty-five percent of the transport tray liners were contaminated with salmonellae on the day of chick placement. At 3 wk, salmonellae serotypes present on the tray liners were widely distributed in the litter of the rearing houses. The results indicated that exposure to salmonellae occurred before culture treatment and continued in the rearing houses during the 6-wk growout period. Salmonellae cecal colonization was decreased (P <.05) in two of the treated flocks at 3 wk and diminished (P <.07) in the third treated flock compared with control flocks. At 6 wk, skin-feather contamination and cecal colonization were decreased (P <.05) in one of the treated flocks whereas no treatment effect occurred in two of the treated flocks compared with controls. The results clearly indicate the necessity of implementing integrated programs to control salmonellae in both the hatchery and rearing house environments. The CCF culture served to enhance salmonellae colonization resistance and may serve as a useful component of an integrated control program.