I have been invited to the Ukraine to give a workshop at a gathering of prominent players in feed manufacturing and pig production. One of the topics I have been asked to discuss is that of additives: how to separate the wheat from the chaff.

Thinking on how to approach this subject, I recalled a conversation I had sometime in the past with a winemaker about what constitutes a good wine. After I developed my own arguments about my favorite wine, he remained silent for a moment, shook his head in obvious disbelief and, turning around, he left me, saying, “Good wine is the one each of us fancies the most.”

Today, I strongly believe feed additives are like wine. Some of us like an additive because we have had good experiences with it. Others vouch with all their professional weight that this same additive is absolutely worthless. Who is wrong, and who is right?

While talking about additives, I must clarify I refer here to products that have an effect at the gut level. Now, with gut microorganisms counting ten times the number of cells in the host, it is quite obvious we are talking about a very complex ecosystem. Would it be possible that a specific mix of microflora in a given population of animals responds favorably to a certain additive, whilst a totally different microflora is indifferent to the same additive?

At the end of the day, it boils down to one of my very first complaints to one sales representative in Midwest, when he was trying to convince me to use his product. I asked him to identify under what conditions his product was giving a documented +70 percent benefit, whereas in others conditions an equally documented -17 percent penalty on growth. Same additive, same animal, different microflora? I am still waiting for that clarification!