A Nutrient Excretion Model is a way of measuring the nutrients that come onto a farm and accounting for where they leave the farm. We’ve been working on Nutrient Excretion Models for a few years and have had great success with them. The model highlights places where farmers are paying to have too much phosphorous fed to the pigs, then paying some more to have that excess phosphorous disposed of. We’ve been working with one farm on this for a couple of years and the savings from not feeding excess phosphorous to the pigs is over $50,000 per year. Add in the savings from not having to dispose of the excess phosphorous in the manure, and that’s a lot of money.
Extension.org has a report up on Nutrient Planning on Swine Farms which covers the same kind of projects on 13 operations. Since this was a funded study, they were able to explore a lot of details that we didn’t get into, but the key conclusion is that it’s worth having a nutrient management plan. If nothing else, you can see where you’re not using nutrients effectively and often there are simple actions that can be taken to reduce leakage. For example, it doesn’t get much easier and cheaper than not feeding the pigs more than they can use!