Publikationsdatenbank

Non-biosecurity based intervention measures against Campylobacter spp. in broiler production (2023)

Art

Hochschulschrift

Autor

Szott, Vanessa Sylvana (WE 10)

Quelle

Berlin: Mensch und Buch Verlag, 2023 — VIII, 115 Seiten

Sprache

Englisch

Verweise

URL (Volltext): https://refubium.fu-berlin.de/handle/fub188/38318

Kontakt

Institut für Tier- und Umwelthygiene

Robert-von-Ostertag-Str. 7-13
14169 Berlin
+49 30 838 51845
tierhygiene@vetmed.fu-berlin.de

Abstract / Zusammenfassung

Campylobacter is a commensal microorganism that generally colonizes the ceca of avian species and is detected in high prevalence in poultry farms. Once colonized with C. jejuni, chickens may remain C. jejuni carriers and excretors until slaughter, which inevitably increases the potential for carcass contamination during processing, in turn allowing transmission of the pathogen to humans. While Campylobacter carriage in broilers is mostly asymptomatic, human infection via contaminated meat causes abdominal pain, fever and acute enteritis and occasionally serious late sequelae like the Guillain-Barré syndrome, reactive arthritis and the Miller-Fisher syndrome. The objective of the present study was to establish a broiler chicken colonization model which targets natural infection and keeps conditions close to commercial poultry production. This model was subsequently used to determine the efficacy of different non-biosecurity based intervention measures to reduce C. jejuni shedding and colonization in broiler chickens. First, we conducted two preliminary studies in which we aimed at determining the lowest inoculation dose necessary to successfully colonize all 20 broiler chickens (of breed Ross 308) after 2 days. For this purpose, we used a dose consisting of 10³ and 104 CFU of a C. jejuni strain. Results revealed that the dose consisting of 104 CFU/500μl fulfilled the desired requirement and was therefore used as an inoculation dose for further experiments. Second, we aimed at examining the effect of different non-biosecurity based intervention measures to reduce C. jejuni colonization in broiler chickens using the established seeder bird model. The study consisted of several experimental groups, each with a specific intervention measure. One group served as a control group while the other group received one of the following treatments: an essential oil (carvacrol), a complex CE culture (Aviguard®), a blend of different organic acids or a combination of two phages. Another group did not receive any treatment but was conducted with an alternative slow-growing breed (Ranger Gold) in combination with a reduced stocking density (25 kg/m2). Each of the measures evaluated showed evident potential to reduce C. jejuni colonization and shedding in broiler chickens during rearing (growing period). However, only one of the measures evaluated, the complex CE culture, proved to be effective in reducing C. jejuni colonization in the cecum. In contrast, colonization of the colon with C. jejuni was significantly reduced by all evaluated measures, except for organic acids. In summary, the complex CE culture can be considered most valuable for the control of Campylobacter in poultry farms because it led to a significant C. jejuni load reduction in the cecum. Even if the other measures did not lead to a reduction in the cecum, they still showed notable potential. Therefore, it cannot be ruled out that further optimizations and new technologies will improve their applicability. Further research, especially large-scale field trials, is needed to investigate the practical effect of distinct control strategies in a commercial poultry production setting.