Mycotoxin Reflections

John A. Doerr, PhD

With a couple of colleagues, I ran a research study some years ago. It was a comparison 
of the individual and combined effects of aflatoxin and ochratoxin in a chicken model.  
The outcome was basically this: Adequate amounts of each were supplied to the chicks and,
individually, the toxicoses they produced were fairly textbook…anyone could have predicted 
the outcomes.  But the combination produced a rather devastating synergistic interaction 
yielding a new disease pattern entirely, and one, when looking at the typical markers for 
each of the two toxins, that was totally different in manifestations.  It defied diagnosis!  
So, yes, those were chickens, not cows.  But what is the fundamental message for all?  
Interaction.  Interactions amongst multiple mycotoxins are unlikely to produce signs and 
symptoms with which we are normally familiar.  Worse, they will produce serious injury in 
your cows.

Now, you might think you understand DON in the dairy cow.  You might have a handle 
on zearalenone in the Holstein you are trying to breed.  But what will you predict 
will happen when these two mycotoxins are combined with emodin, fusaric acid, mycophenolic 
acid and perhaps 5-25 others in the ration (recent reports show that around 80% of all feeds 
sampled have more than 20 mycotoxins concurrently)?  The combination of multiple mechanisms 
of action, sites of damage, etc. can produce effects both unexpected and unrecognizable as 
mycotoxin issues.  This is the fundamental problem with feed-borne mycotoxins…they can and 
do interact.

I’d love to stop there, but interaction is not confined to just mycotoxin on mycotoxin.  
These fungal poisons interact with stressors, such as heat, cold, social stress, oxidative 
stress, etc.  They interact with disease agents, viral, bacterial, or parasitic.  And in 
many cases, the outcome will be a misdiagnosis which points the blame at an infectious 
agent or management or other when the real initiator and potentiator of the problem is a 
mold toxin in the feed. 

Perhaps it is rather important to have a sound, continuous strategy for coping with multiple 
mycotoxins in any modern dairy farm, yes?  And what can you turn to for relief from this 
egregious problem?  Select DTX pretty much covers the gamut in the mycotoxin world.  It is 
effective against these multiple toxin contaminations of feeds and consequences those could 
produce in your herd.  And what better time than now to try Select DTX on your farm!  Your 
Select Sires salesperson or your Agrarian Solutions rep can give you details on a money-saving 
promotion for this product that extends through the end of April.  Don’t miss out.