Tryptophan Attenuates the Effects of OTA on Intestinal Morphology and Local IgA/IgY Production in Broiler Chicks.

Fernando Galdino Ricci,Leticia Rodrigues Terkelli,Ana Angelita Sampaio Baptista,Larissa Justino,Beatriz Queiroz Dos Santos,Elisa Yoko Hirooka,Emerson José Venancio,Ana Paula Frederico Rodrigues Loureiro Bracarense,Alexandre Oba,Eiko Nakagawa Itano,Bianca Dorana De Oliveira Souza

doi:10.3390/toxins13010005

Abstract

Ochratoxin A (OTA) is a mycotoxin produced by species of Penicillium and Aspergillus that can contaminate products of plant origin that are used as animal feed. Through oral exposure, this mycotoxin primarily affects the chicken gastrointestinal system. The present study evaluated the intestinal toxic effects of OTA and the introduction of L-tryptophan to alleviate these effects in chickens. One-day-old chicks were exposed to a single OTA dose (1.4 mg/kg body weight—b.w.) and treated with or without four daily doses of L-tryptophan (100 mg/kg b.w.). Duodenal villus height/crypt depth, fecal immunoglobulin A/immunoglobulin Y (IgA/IgY) levels, and duodenal positive immunoglobulin A cells (IgA+) were evaluated by histology, ELISA, and immunohistochemistry, respectively, on the 14th day. There were significant changes in the duodenal villus height, crypt depth, and levels of fecal IgA/IgY and duodenal IgA+ cells (p < 0.05) in groups exposed to OTA. On the other hand, groups exposed to OTA and treated with L-tryptophan showed similar levels of villus height, IgA/IgY levels, and duodenal IgA+ cells to those of the control group (p > 0.05). In conclusion, exposure to a single dose of OTA orally induces changes in intestinal morphology, levels of IgA/IgY antibodies, and IgA+ cells. Thus, treatment with L-tryptophan may be a valid alternative means to reduce the harmful effects of OTA on the intestinal mucosa, which requires further study.

Highlights

Ochratoxin A (OTA) is a mycotoxin produced by several species of the genus Penicillium and Aspergillus [1,2,3]
The current study investigated the effects of a single oral exposure to OTA on duodenal intestinal histomorphology, local immunoglobulin A/immunoglobulin Y (IgA/immunoglobulin Y (IgY)) levels, and local positive immunoglobulin A (IgA) cells (IgA+) in broiler chickens and introduced an L-tryptophan treatment to verify whether it can mitigate the possible toxic effect of OTA
Treatment with L-tryptophan in one of the groups exposed to OTA resulted in a similar villus height to that of the control group and different from the group exposed only to OTA, suggesting the neutralizing capacity of L-tryptophan (Figure 2)

Summary

Introduction

Ochratoxin A (OTA) is a mycotoxin produced by several species of the genus Penicillium and Aspergillus [1,2,3]. The growth of these fungi, in plant products is favored by climatic conditions such as temperature and humidity. Some of these products are used as ingredients in poultry feed, and when contaminated by OTA, they can cause animal intoxication [4,5]. OTA is classified by the International Agency for Research on Cancer in Group 2B [13] and for the European Union, the recommendable OTA limit is 0.1 mg/kg in complementary ingredients for poultry feed [14]

Methods

Results

Conclusion