A few days ago, Peter Best sent me a note about Sweden changing to the net energy system in formulating diets for pigs. Along with my natural reaction, “it was about time,” it also reminded me of a funny but highly educational experience I had several years ago.
A customer of mine, a premix company, asked me to visit one of their clients to convince him that using the metabolizable energy system (as employed by this premix manufacturer in formulating feeds for this pig producer) was as good as the net energy system (which, as it happened, was advocated by a competitor). Now, from previous information, I knew this pig producer was using quite a bit of "unconventional" ingredients, and, as such, as every textbook will tell you, the net energy system was the right thing for him. So, I refused the assignment, but they sent someone else.
You can guess that I lost a customer, but my customer also lost their customer to competition -- and it was a significant pig producer with 15,000 sows. Had this pig producer been using just cereals and soybean meal, I would have had no problem explaining to him that although in theory the net energy system is superior to all, the metabolizable energy system is as good when it is about the few conventional ingredients everyone uses most of the time. But, when it comes to formulating pig feeds with "out of the box" ingredients, it pays to use the net energy system.