Interpretive Summary: Interpretive Summary: Dietary deoxynivalenol and oral lipopolysaccharide challenge differently affect intestinal innate immune response and barrier function in broiler chickens
By: Anne Wallace
This article is published in the December 2018 issue of the Journal of Animal Science. Researchers evaluated the effects of deoxynivalenol (DON) and lipopolysaccharide (LPS), two known microbial toxins, on the intestinal health of broiler chickens.
The Fusarium fungal mycotoxin DON has been previously shown to detrimentally modify the intestinal barrier of the duodenum and jejunum in broiler chickens (1). The bacterial toxin, LPS, also has known pro-inflammatory effects in the gut. The authors of this study, therefore, chose to look at dose-response relationships of DON and the additional challenge of LPS, and how these conditions might affect the intestinal health of broiler chickens.
In this study, 80 one-day-old broiler chicks were kept in a controlled environment and randomly assigned to one of eight treatments: control diet with no LPS (0 DON + con), 2.5 mg DON per 1 kg of control feed (2.5 DON + con), 5 DON + con, and 10 DON + con. Additionally, an oral LPS challenge was added before the end of the treatment period was to the four diets in half of the chickens (0 DON + lps 2.5 DON + lps, 5 DON + lps, and 10 DON + lps). The experimental period lasted five weeks, upon which chickens were euthanized. The authors then looked at the expression of genes and immune markers associated with gut health and gut barrier integrity in collected gut tissue (e.g., TLR2, IL6, and CLDN1).
Results indicated that the highest concentration of DON (10 DON) reduced dry matter intake (DMI) by 13%, which was a significant change, compared to the control diet. There was also a tendency for decreasing weight gain in the broiler chickens as the concentration of DON was increased. Genes involving tight-junctions and pro-inflammatory signaling were also altered by increasing concentration of DON. The addition of LPS increased markers indicating inflammation and intestinal permeability in the jejunum. However, researchers reported that it did not potentiate the effects of DON, as previously hypothesized.
Overall, this study does confirm that DON mycotoxins detrimentally impact the gut health of broiler chickens. New questions about how DON might interact with other dietary toxins is warrant. A more prolonged course of LPS may have had a different effect than a single dose. The authors hypothesized that reduced DMI observed in 10 DON chickens might have been due to increased immune response, although changes to gut microbiota might also account for this difference. Overall, more in-depth studies looking at the specific effects of DON on inflammatory markers and gut barrier function are warranted.
(1) Awad, W. A., Hess, M., Twarużek, M., Grajewski, J., Kosicki, R., Böhm, J., & Zentek, J. (2011). The impact of the Fusarium mycotoxin deoxynivalenol on the health and performance of broiler chickens. International journal of molecular sciences, 12(11), 7996-8012.
To view the full article, visit the Journal of Animal Science.