Mycotoxin Contamination in Japanese Domestic Feed

This study summarizes the levels of the mycotoxins aflatoxin B₁, deoxynivalenol, zearalenone, ochratoxin A, and fumonisin B₁ in domestic feed produced in Japan. We collected samples of Japanese domestic feed used in livestock farming establishments or by small farmers from April 2012 to March 2014, and measured mycotoxin concentrations in each sample. Regarding corn, deoxynivalenol had the highest detection rate (84%), maximum value (2370 µg/kg), and mean value (400 µg/kg). These results suggest that deoxynivalenol is a major mycotoxin contaminant in Japanese-produced domestic feed. Zearalenone and fumonisin B₁ presented the second highest detection rates. The maximum concentration of zearalenone was 1200 µg/kg in grass samples, but its median was under 25 µg/kg, and, overall, it occurred at low concentrations. The detection rate of fumonisin B₁ was about 30%, but its maximum concentration in corn was 2400 μg/kg, slightly higher than deoxynivalenol. Overall, mycotoxin concentrations were lower in grass than in corn. Although deoxynivalenol was detected in samples collected from all regions, concentrations in samples from Hokkaido were particularly high. Fumonisin B₁ was mainly distributed in Kanto and the southern regions. Concentrations of ochratoxin A and aflatoxin B₁ were low; however, the maximum concentration of aflatoxin B₁ was 22 μg/kg in corn. Although aflatoxin B₁ and ochratoxin A were rarely detected, they occasionally presented high levels, therefore requiring attention. Overall, mycotoxins produced by Fusarium sp. fungi require attention in Japanese-produced domestic feed.