An anti-microbial composition for treating animal feed, comprising:1 to 90 wt. %, based on the total weight, of a C1 to C24 organic acid,1 to 90 wt. %, based on the total weight, of trans-2-hexenal provided it constitutes at least 5 wt. % of the organic acid and aldehyde mixture,0 to 50 wt. % based on the total weight of terpenes,0 to 20 wt. % based on the total weight of a surfactant, andwater.
