Author
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Stern, Norman |
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Submitted to: World Poultry
Publication Type: Proceedings Publication Acceptance Date: 3/16/2004 Publication Date: 7/15/2004 Citation: Stern, N.J. 2004. Potential for on-farm control of Campylobacter in broilers. Poultry Science. 81(S1):405. Interpretive Summary: Bacteria antagonistic to the human pathogen, Campylobacter jejuni, were isolated from commercial poultry operations. Proteins produced by these antagonists (bacteriocins) were purified and characterized. Subsequently, the bacteriocins were microencapsulated and mixed with chicken feed. Groups of chickens colonized with Campylobacter were either provided the bacteriocin emended feed or not treated with bacteriocins. Levels of the organism were compared between the groups. Levels were consistently reduced at least one-million fold in the treated animals in 15 replicate trials. Bacteriocins as therapeutic treatment of chickens may reduce human exposure to Campylobacter. Technical Abstract: Campylobacter jejuni is thought to be transmitted most frequently through exposure to poultry products. We screened 365 Bacillus/Paenibacillus spp. isolates from poultry production to identify potentials for anti-C. jejuni activity. Zones of C. jejuni inhibition surrounding 56 isolates drew interest. One novel antagonistic Bacillus circulans (NRRL B-30644) and two Paenibacillus polymyxa (NRRL B-30507 & NRRL B-30509) strains were identified. The cell-free, ammonium sulfate precipitate from each candidate culture also created zones of C. jejuni inhibition in spot tests. Exposure of the crude extract to protease enzymes inactivated Campylobacter inhibition, consistent with bacteriocin definition. The peptides were characterized by SDS-PAGE electrophoresis, isoelectric focusing, and amino acid sequencing. In 15 separate experiments, one or two days-post-hatch chicks were colonized with challenges of ~2 X 106 cfu C. jejuni, and placed in isolation units. Three days before sampling, therapeutic feeds were provided ad-libitum. This feed consisted of purified bacteriocin (0.25 or 0.5 g) micro-encapsulated in polyvinyl-pyrrolidone and incorporated into 1 Kg of chicken feed. Therapeutic treatment consistently reduced C. jejuni colonization by at least 100,000 fold over the untreated chicks. Therapeutic bacteriocin treatment of mature chickens prior to slaughter may substantially reduce public exposure to this organism. |
