Deepoxy-deoxynivalenol (DOM-1), a derivate of deoxynivalenol (DON), exhibits less toxicity on intestinal barrier function, Campylobacter jejuni colonization and translocation in broiler chickens

Background Intestinal epithelial cells are challenged by mycotoxins and many bacterial pathogens. It was previously shown that the mycotoxin deoxynivalenol (DON) as well as Campylobacter (C.) jejuni have a negative impact on gut integrity. Recently, it was demonstrated that DON increased the load of C. jejuni in the gut and inner organs. Based on this finding, it was hypothesized the DON metabolite (deepoxy-deoxynivalenol, DOM-1) should be able to reduce the negative effects of DON on colonization and translocation of C. jejuni in broilers, since it lacks the epoxide ring, which is responsible for the toxicity of DON. Methods A total of 180 broiler chickens were housed in floor pens on wood shavings with feed and water provided ad libitum. Birds were divided into six groups (n = 30 with 5 replicates/group): 1. Control, 2. DOM-1, 3. DON, 4. DOM-1 + C. jejuni, 5. DON + C. jejuni, 6. C. jejuni. At day 14, birds of groups 4, 5 and 6 were orally inoculated via feeding tube (gavage) with 1-ml of a PBS suspension containing 1 x 10(8) CFU of C. jejuni NCTC 12744. The performance parameters: body weight (BW), body weight gain (BWG), and feed intake of the birds were determined. At 7, 14, and 21 days post infection, samples from liver, spleen, duodenum, jejunum and cecum were aseptically collected and processed for bacteriological investigations. Finally, at each killing time point, segments of duodenum, jejunum and cecum were harvested and prepared for Ussing chamber studies to measure the paracellular mannitol fluxes. Results A significant decrease in body weight was observed for chickens receiving the DON diet with or without C. jejuni compared to the other groups. Furthermore, it was found that the co-exposure of birds to DON and C. jejuni resulted in a higher C. jejuni load not only in the gut but also in liver and spleen due to increased paracellular permeability of the duodenum, jejunum and cecum. On the contrary, DOM-1 supplementation in the feed improved the birds' performance and led to a better feed conversion ratio throughout the trial. Furthermore, DOM-1 did not negatively affect gut permeability and decreased the C. jejuni counts in the intestine and internal organs. Conclusion Altogether, the presence of DOM-1 in the feed as a result of the enzymatic biotransformation of DON leads to a lower C. jejuni count in the intestine and better feed conversion ratio. Moreover, this study demonstrates that the detoxification product of DON, DOM-1, does not have negative effects on the gastrointestinal tract and reduces the Campylobacter burden in chickens and also the risk for human infection.

• Interactions of the Fusarium mycotoxin deoxynivalenol (DON) and its` derivate deepoxy-deoxynivalenol (DOM-1) with Campylobacter jejuni in the intestine of broiler chickens.

Biomin Holding GmbH, Research Center
Veterinärmedizinische Universität Wien