Impact of litter salmonella status during feed withdrawal on salmonella recovery from the broiler crop and ceca

Authors: Buhr, Richard - Jeff; Bourassa, Dianna; Hinton Jr, Arthur; FAIRCHILD, BRIAN - University Of Georgia; RITZ, CASEY - University Of Georgia

Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/30/2017
Publication Date: 12/14/2017
Citation: Buhr, R.J., Bourassa, D.V., Hinton Jr, A., Fairchild, B.D., Ritz, C.W. 2017. Impact of litter salmonella status during feed withdrawal on salmonella recovery from the broiler crop and ceca. Poultry Science. 96:(12)4361-4369. doi.org10.3382/ps/pex231.

Interpretive Summary: Research was conducted to evaluate the impact of litter Salmonella status during feed withdrawal prior to cooping for processing on the subsequent Salmonella recovery from the crop and ceca segments of the alimentary tract following feed withdrawal. Pens of broilers in separate rooms were challenged with marker strains of either Salmonella Montevideo or Salmonella Heidelberg. Three days post-challenge, a 12 h feed withdrawal was initiated at the same time as one pen of broilers was switched between rooms for each Salmonella strain. Non-challenged broilers were also added to the Salmonella challenge pens. The litter of each pen was sampled before and after the feed withdrawal period, the broilers euthanized, and the crop and ceca aseptically removed for Salmonella isolation. Results indicate that only the challenge Salmonella strain was recovered from the litter in challenge pens where broilers were not moved, while both Salmonella strains were recovered from the litter of the switched pens. From the broilers that remained in the challenge pens the challenge Salmonella strain was recovered from 70% of the crops and from 81% of the ceca. From broilers that were switched between pens, the challenge Salmonella strain was recovered from 62% of the crops and from 75% of the ceca, and the switched pen’s litter Salmonella strain was recovered from 18% of the crops but not from the ceca. From the non-challenged broilers placed into the Salmonella challenge pens Salmonella was recovered from 48% of the crops and from only 5% ceca. Evaluating the results from broilers that were switched between Salmonella challenge pens indicates that the recovery of Salmonella from the crop of broilers following feed withdrawal (on Salmonella contaminated litter) appears to mainly depend on the initial challenge Salmonella (65%) and less on the litter Salmonella (15%) status during the feed withdrawal period. In contrast, only the initial challenge Salmonella was recovered from the ceca (81%) from broilers that remained in challenge pens or were switched between Salmonella challenge pens. However, when non-challenged broilers were placed into the Salmonella challenge pens and commingled during the 12 h feed and water withdrawal period, it was possible to recover the pen litter Salmonella from the ceca at a low level of 5%. This research indicates that feed withdrawal periods as long as 12 h on contaminated litter will not increase the likelihood of intestinal Salmonella proliferation in the ceca.

Technical Abstract: Research was conducted to evaluate the impact of litter Salmonella status during feed withdrawal on Salmonella recovery from the crop and ceca following feed withdrawal. In 4 experiments, pens of broilers in separate rooms were challenged with marker strains of either Salmonella Montevideo or Salmonella Heidelberg. Three days post-challenge, a 12 h feed withdrawal was initiated and one pen of broilers was switched between rooms for each Salmonella serotype. In experiments 3 and 4, non-challenged broilers were also added to the Salmonella challenge pens. The litter of each pen was sampled before and after the feed withdrawal period, the broilers euthanized, and the crop and ceca aseptically removed for Salmonella isolation. Results indicate that only the challenge Salmonella serotype was recovered from the litter in challenge pens where broilers were not moved, while both Salmonella serotypes were recovered from the litter of the switched pens. Salmonella was recovered from 52/80 crops and from 65/80 ceca of challenged broilers that remained in the challenge pens. The challenge Salmonella serotype was recovered from 57/80 crops and from 58/80 ceca, and the switched pen’s litter Salmonella serotype was recovered from 17/80 crops but not from the ceca in broilers challenged with Salmonella and then switched between pens. For experiments 3 and 4, Salmonella was recovered from 19/40 crops and from only 2/40 ceca from the non-challenged broilers placed into the Salmonella challenge pens. The results from broilers that were switched between Salmonella challenge pens indicate that the recovery of Salmonella from the crop of broilers following feed withdrawal (on Salmonella contaminated litter) appears to mainly depend on the initial challenge Salmonella (65%) and less on the litter Salmonella (15%) status during the feed withdrawal period. In contrast, only the initial challenge Salmonella was recovered from the ceca (81%) from broilers that remained in challenge pens or were switched between Salmonella challenge pens. However, when non-challenged broilers were placed into the Salmonella challenge pens and commingled during the 12 h feed and water withdrawal period, it was possible to recover the pen litter Salmonella from the ceca at a low level of 5% (2/40).