APPLICATION OF DIRECT-FED MICROBIAL BACTERIA AND FRUCTOOLIGOSACCHARIDES FOR SALMONELLA CONTROL IN BROILERS DURING FEED WITHDRAWAL

Providing direct-fed-microbial (DFM) bacteria and fructooligosaccharid es (FOS) for the control of potential escalation of Salmonella coloniz ation during simulated feed withdrawal and confinement was assessed. E ight hundred and eighty broilers (16 pens; 55 chicks per pen) were rea red to 6 wk of age. Chicks were sprayed with a solution containing 10( 6) nalidixic-acid resistant Salmonella typhimurium(NR) cells per milli liter on the 2nd d after hatching. Because this first challenge did no t yield a high infection rate, chickens were rechallenged per os at Da y 18 by providing water containing 10(7) cells of S. typhimurium(NR) p er milliliter. At 3 and 5 wk of age, 10 birds per pen were euthanatize d and cecal Salmonella were quantified (log colony-forming units per g ram). Feed was removed from all pens at 6 wk, and pens were randomly a ssigned to be either the treatment group or the control group. The tre atment groups were provided a DFM (mixture of nine bacteria) and FOS 5 0(R) (10%) in the drinking water. The control groups received drinking water only. After 6 h of feed withdrawal, chickens were cooped (eight per coop) and held 10 h. Immediately after confinement, 10 chickens w ere used for cecal enumeration of S. typhimurium(NR) Salmonella coloni zation declined from 99% at 3 wk to 44% at 5 wk. After feed withdrawal , application of the treatment, and confinement, 11 and 14% of the tre ated and control groups, respectively, yielded S. typhimurium(NR) by d irect plating from ceca (3.87 and 3.75 log(10) cfu/g, respectively). N o difference (P > 0.05) in Salmonella colonization occurred between th e treated and the control groups; however, enrichment of ceca (incubat ion in nutrient broth at 37 C for 24 h) yielded a higher incidence of S. typhimurium(NR) in the control groups (32% in the treated vs 51% in the control). Ceca weights were greater in the treated group (P < 0.0 5). Simulated feed withdrawal and confinement did not escalate Salmone lla colonization in the chicken ceca.