While hundreds of mycotoxins have been identified, only a relative few are routinely monitored in feed and feed ingredients. One such mycotoxin, aflatoxin, has raised concerns among poultry producers for over 50 years, as it can cause acute and chronic ailments at levels as low as 20 ppb. Mixer-added water, used to enhance pelleting productive capacity and quality, could inadvertently create a substrate suitable for aflatoxin-producing species, posing a microbiological risk to poultry. Therefore, an experiment was conducted to evaluate the effect of dietary treatment (DT; Control, 1.50% mixer-added water, and 0.25% Azomite and 1.50% mixer-added water) and simulated storage season (Summer or Fall) on total aflatoxin (TAF) content, water activity (A w ), and colony counts of feed inoculated with A. flavus over a 6-day storage period. During this period, samples were collected at four Time Points: Day 0 before inoculation, Day 0 after inoculation, Day 3 post-inoculation, and Day 6 post-inoculation. The interaction of Season and Time Point influenced A w (P = 0.005), where Summer storage conditions decreased A w relative to Fall storage conditions on Day 6 post-inoculation, likely due to water evaporation. Total aflatoxin increased with the 6-day storage period but did not exceed critical levels within the confines of this experiment. In summary, utilizing 1.50% mixer-added water as a pelleting aid may not pose a microbiological risk to poultry when incorporated into feed manufactured with low-moisture corn and stored for less than 7 days. However, the reader should be aware of the risk associated with higher-moisture primary ingredients.
Knarr et al. (Wed,) studied this question.