Inoculants: Claims you can count on

By Jon Urness
In America, we’re proud to say we live in the land of the free.  Most often, that’s a good thing.  But when it comes to silage additives and how they’re scrutinized and marketed, maybe we’d have to say “not so much.”

Here in the land of wide open spaces and free markets, it’s fairly easy to put together a silage additive simply by choosing a few likely characters for bacteria, mixing them in a bottle, slapping on a label, and touting it as being well researched and proven – with little or no interference from regulators such as FDA.

Whether you’re a livestock producer using these products or a custom harvester applying them, it would be nice to be able to separate the wheat from the chaff.  Our universities do a nice job of evaluating silage additives, but research dollars are scarce.  And, far too often, the research results are applied broadly over wide segments of the market.

For example, Lactobacillus plantarum MTD/1 is the specific bacteria in Vita Plus Crop-N-Rich inoculant and was well researched and proven in Dr. Richard Muck’s lab at the University of Wisconsin-Madison, in Dr. Limin Kung’s lab at the University of Delaware, and through Dr. Keith Bolsen’s work on dry matter loss at Kansas State University.  Some companies take those results and make blanket statements, implying that MTD/1’s qualities are shared their inoculants containing L. plantarum.  However, there are literally hundreds of different strains of L. plantarum and they don’t necessarily have the same characteristics or qualities as the strain used in our Crop-N-Rich inoculant.

Although companies are free to use this strategy in the U.S., it’s a far different story in the European Union.  Thanks to EU food safety regulations, we can be assured that Crop-N-Rich MTD/1 has been closely scrutinized long before it ever reaches our farms.

Several years ago, EU food safety regulators determined that silage additives should be classified as feed additives and, therefore, must require authorization for their sale and distribution.  Products that are not approved cannot be marketed and must be removed from the market.  Five areas of documentation are required to receive authorization:

• Public and scientific studies
• Identity and condition of use of the additive
• Study of safety, including safety to animals, consumers, the environment and workers
• Studies concerning efficacy
• Post-market monitoring

Of the 2,616 substances submitted as feed additives under these new regulations, only 43 percent were approved.  That means 57 percent of the feed additives submitted received an eventual ban in the EU.  Breaking out silage additives from this group, it’s clear to see that cutting the mustard was even more difficult for silage inoculants.  Of 402 silage additives submitted for authorization, only 95 (24 percent) were approved, including L. plantarum MTD/1, which is found in our Crop-N-Rich inoculant.  Forty-four L. plantarum-based silage additives were “black listed” during this evaluation and banned from the market.

A submitted product can be denied based on any of the five criteria listed above, but proof of efficacy is often a point of failure for silage additives.

For silage additives, evidence must show the ability to enhance fermentation in an easy-to-ferment feed, a moderately-difficult-to-ferment feed, and a difficult-to-ferment feed to be significantly effective.  Under these definitions, easy-to-ferment feeds include those with relatively high water-soluble carbohydrate content (greater than 3.0 percent), such as corn silage.  Moderately-difficult-to-ferment feeds contain intermediate levels of water-soluble carbohydrates (1.5 to 3.0 percent), such as fescue and wilted alfalfa.  Difficult-to-ferment feeds are lower in carbohydrates and would include orchard grass and other legumes.  Based on these criteria, L. plantarum MTD/1 has been deemed “significantly effective” under the definitions of the EU food safety regulation.

With all the wannabe and lookalike forage inoculants on the U.S. market, it makes me wonder how they would stand up to the scrutiny of EU food safety laws.  While these laws don’t apply in the U.S., time will tell if requirements in the U.S. and EU will become more similar than different.  In the meantime, when evaluating any forage product here in America, insist on seeing the proof of performance and what standards have been applied to back up statements on effectiveness.

This article was originally written for the Vita Plus Forage Review in 2010.

About the author:  Jon Urness is the Vita Plus national forage specialist.  He grew up on his family’s five-generation homestead dairy near Black Earth, Wis. and still lives there today.  He graduated from the University of Wisconsin-Madison in 1977 with a bachelor’s degree in agricultural journalism.  Since 1992, Urness has provided on-farm dairy nutrition consulting in southwest Wisconsin as a Vita Plus employee owner.  He has also taken on the forage marketing responsibilities outside of the traditional Vita Plus market.