Correlation between naturally occurring feed mycotoxins and necrotic enteritis severity in broiler birds.

Authors: Shanmugasundaram, Revathi

Submitted to: Poultry Science Association Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 5/4/2021
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Poultry feeds are naturally contaminated with aflatoxins, fumonisins, deoxynivalenol, acetyldeoxynivalenol, zearalenone and several other mycotoxins. Mycotoxins increase gut permeability and can exacerbate the severity of necrotic enteritis in poultry. This study quantified and correlated the feed mycotoxin content to the necrotic enteritis disease score and gut permeability. Six experiments were conducted over a period of nine months. In all six studies, birds were raised in cages and challenged with 5x103 Eimeria maxima oocysts on d14 and with 1x108 CFU Clostridium perfringens on d19, 20, and 21. All studies were replicated in 8 pens. At d21, three birds per pen were sacrificed and scored for necrotic enteritis disease severity, and gut permeability was measured by FITC-D gavage assay. All studies had the same feed formulation except for the source of grains. Feed was quantified for aflatoxin B1, B2, and G1, fumonisin B1, B2, B3, dexoynivalenol, acetyldeoxynivalenol and zearalenone content by HPLC. The total aflatoxin content of Diets 1 to 6 was 21.2, 5.2, 3.8, 3.5, 3 and 2.5 ppm. Diet 1 had 16.7 ppm aflatoxin B1, while Diets 3, 5, and 6 had no aflatoxin. Diet 3 had the highest concentration of total fumonisins of 3.5 ppm. Diet 4 had 2.3 ppm aflatoxin B1 and 1.5 ppm total fumonisins. Diets 5 and 6 had 366 and 123 ppb of zearalenone. Birds fed Diet 1 had the highest (P < 0.05) Wilcoxon/Kruskal-Wallis necrotic enteritis score means, which was significantly higher than the other experiments. Birds fed Diets 5 and six had the lowest Wilcoxon/Kruskal-Wallis necrotic enteritis score means. Analyzing the data from all six experiments, there was a positive correlation between feed total mycotoxin (r = 0.48) and total aflatoxin (r = 0.48) content with the necrotic enteritis disease severity. There also was a positive correlation between feed total mycotoxin (r = 0.67) and total aflatoxin (r = 0.67) content with serum FITC-D content. It can be concluded that naturally occurring feed mycotoxins, particularly aflatoxins, at levels above 21.2 ppm exacerbates necrotic enteritis disease severity by increasing gut permeability.