Effect of delayed placement on the incidence of Campylobacter jejuni in broiler chickens

An experiment was conducted with broiler chickens to evaluate the effect of delayed placement on reused litter and the isolation of Campylobacter jeju ni. The experiment also assessed the presence of C. jejuni in the crop foll owing feed withdrawal periods in cages vs floor environments. Trial 1 utili zed 320 female broiler chicks obtained: from a commercial hatchery. The chi cks were randomly placed into the following experimental groups that were r eplicated four times with 20 chicks per pen: 1) 0-h, 2) 24-h, 3) 48-h, and 4) 72-h delayed placement. Fecal samples were collected via the cloaca at 7 , 14, 21, and 28 d of age; enriched in Bolton broth; and plated onto BBL ag ar. Campylobacter jejuni was isolated at 1 wk of age in the 48- and 72-h ex perimental groups but did not differ significantly from the others. Samplin g results at 14 d of age showed that 63, 68, 73, and 80% of chicks were pos itive for the 0-, 24-, 48-, and 72-h treatments, respectively. At 28 d of a ge, 100% of all chicks sampled tested positive. In Trial 2, 60 market age b roilers were evaluated for the presence of C. jejuni in the crop by subject ing them to 0-, 4-, 8-, 12-, and 16-h feed withdrawal times on litter or in wire cages. Crops were collected aseptically from the broilers, stomached, enriched in Bolton broth, and then plated on BBL agar. There were no signi ficant (P < 0.05) differences between cage and floor withdrawal times for t he presence of C. jejuni in the crop samples of broilers; however, there we re significant differences in the length of withdrawal on the presence of C . jejuni. Collectively, these results suggested that the isolation of C. je juni occurred earlier in broilers that were subjected to delayed placement on reused litter and that extended feed withdrawal times in cages or on lit ter may increase the possibility that the crop of broilers may contain a hi gher isolation rate of C. jejuni.