Choosing an inoculant 101 (Dr. Michelle Windle)
Most producers are aware that inoculants can help minimize shrink, avoid heating, and improve forage quality, animal health, and performance. Left untreated, naturally occurring microorganisms on plants in the field drive fermentation. Inoculants offer a tool to control this fermentation.
It’s tempting to quickly check off yet another “to-do” on your long list and make a hasty decision about inoculants. To complicate the matter, the government has limited oversight of inoculant claims. Therefore, an inoculant that boasts “improved aerobic stability” never needed to prove this claim scientifically. That leads us to ask, “How should one choose an inoculant if the claims are not verified or trustworthy?”
First, take into account that any decision that affects forage quality will impact the farm every day. Then, make a decision based on function, research and trust.
The main objectives when ensiling are to minimize shrink and preserve forage quality. Inoculants achieve this by enhancing fermentation and preserving aerobic stability. Up-front fermenters drop pH quickly, which can prevent the growth of undesirable microorganisms (such as Clostridia), and can minimize protein degradation and shrink. Some examples are Lactobacillus plantarum, and Pediococcus pentosaceus, although numerous other area available on the market. Inoculants containing Lactobacillus buchneri can prevent spoilage.
In general, no one bacterium is dual-purpose; up-front fermenters cannot consistently improve aerobic stability, and vice versa. Therefore, many companies offer a combination inoculant, which can include multiple strains of bacteria designed to have multiple functions.
When choosing the best inoculant for your situation, first consider what issue you want to solve. If you have a difficult-to-ensile crop, use an up-front fermenter to control the fermentation. If you have reason to believe the crop will be aerobically challenged, use an inoculant that contains L. buchneri.
Independently conducted, statistically analyzed, published research is the most reliable type of research. An example is a published journal article. A quality inoculant will have this research to back up claims – more research means better credibility.
Unfortunately, only a handful of inoculants have this type of research. Ask your inoculant salesperson for published research. Most research in brochures was conducted by the company and, therefore, may be biased.
Not all bacteria with the same name behave similarly. The numbers and letters after a bacterial name indicate the specific strain, similar to a barcode. Look for research on your particular strain only.
The relationship that a producer has with an inoculant salesperson should be based on many factors. Certainly, the “gut feeling” goes a long way, but credentials and performance have an impact too. Look for reliable support that you can call upon in a time of need. If you have a trusted nutritionist, ask for his or her input.
Making the right decision
Just as you would research a car before buying one, inoculants should be purchased only after adequate research. Choose the right type of inoculant, ask for independently conducted, peer-reviewed research, and ensure that you will have a trusted support network as you go through the silage season.