As preserved forages are more likely to harbour moulds and associated mycotoxins than dry forages when anaerobic conditions are not strictly controlled, silages do present an enhanced risk of mycotoxin contamination.

The multiplicity of ingredients in complete diets may increase the probability of multiple mycotoxin contamination but decreases the risk of high mycotoxin concentrations because any one feed ingredient is diluted in the final diet. This will often keep very specific mycotoxin symptoms from the herd but will lead to more general symptoms such as suboptimal performance.