As soon as the corn silage is chopped, a race against time begins. Growers understand the value of high-quality forages. They also know it is important to protect it with a quality silage inoculant. Inoculants give corn silage growers an advantage, protecting the nutrient value of feed in storage. However, inoculants are just to be managed at harvest. It is important for growers to manage inoculants from harvest to storage to feed in order to maximize the value of their silage.
Harvest : Ideally, inoculant protection starts at the forage chopper. To ensure correct application rates, growers must pay attention to inoculant applicator calibration, as accurate application rates are critical to overcome naturally occurring epiphytes, or bad bugs.
There are three keys to successful applicator preparation and calibration:
- Read and follow the label for the inoculant purchased. Every manufacturer formulates and packages inoculant differently.
- Clean and calibrate applicators at the beginning of the season and between harvests. Make sure to replace filters and nozzles to ensure uniform application and use multiple nozzles when applying inoculants on balers and bagger equipment.
- Match application rates with forage delivery rates. Output from an applicator is different when delivering 300 tons per hour to the silo than when delivering 50 tons per hour.
Accurate calibration is an essential element of the inoculant investment. Excess inoculant is uneconomical, while applications below the recommended level may limit performance of the product.
Bunker Storage: Inoculants with a strain of Lactobacillus buchneri (L. buchneri) dramatically improve aerobic stability at feedout. When combined with crop-specific, fermentation-controlling bacteria, they deliver a “one-two punch” that protects nutrients during feedout and the up-front portion of the fermentation process.
Fermentation failures occur when the face of the silage bunker is exposed to too much oxygen, either from poor packing or slow feedout, resulting in the growth of dormant aerobic organisms such as yeasts, molds or bacillus. These growing organisms consume energy and often cause heating that decreases quantity and quality of silage.
As these organisms consume sugar, carbohydrates and lactic acid, pH levels rise, resulting in more spoilage and additional organisms to grow, causing additional damage. Inoculants with the specific L. buchneri strain convert the lactic acid into acetic acid. Acetic acid is a good yeast and mold inhibitor, which reduces heating and nutrient loss during feedout, resulting in a more consistent and stable feed with higher forage quality. A high-quality L. buchneri inoculant can keep feed cool and fresh for cows longer, in some cases providing more than 40 hours of additional stability.
Every grower knows fresh feed is critical for livestock. Fresh forage has only a few hours before it starts to heat, losing nutritional quality and beginning to decompose. Using fermentation aided by inoculants can help stabilize silage, giving it a shelf life lasting many years.
Feed: Some silage inoculants do much more than preserve forage nutrients in the bunker. Inoculants with a specific L. buchneri strain also known as fiber-technology inoculants, produce specific enzymes that attack the ester bond linking cell wall polysaccharides to indigestible lignin, resulting in more rapid fiber digestion by rumen bacteria.
This provides grower with the opportunity to lower corn grain supplementation in feeds. As the lignin is decoupled, it leaves less resistance to rumen bacteria, allowing them to digest more fiber and faster. This allows growers to include more fiber-technology corn silage, which ultimately produces a higher forage-based ration, healthier for dairy cows. The rapidly digested fiber also allows for more energy to be obtained from the fiber in the limited time it remains in the rumen of high-producing animals.
Fiber-technology inoculant on silage can also help to lower protein supplementation. As fiber and lignin become decoupled, they increase the amount of fiber rumen microbes can utilize during rumen residence times. This results in increased microbial protein production which allows cows to meet protein requirements for maintenance, growth, reproduction and milk production. As inoculants improve, they become more of a management tool to improve nutritive value rather than just insurance policies that reduce potential silage losses. As the industry evolves, nutritionists must fully understand what the inoculant does, as rations may need to be altered to fully realize the value of the product.
When switching to a fiber-technology inoculant, monitor cows and modify their diet gradually to account for the changes in rate and extent of fiber digestibility compared to old-crop silages. This is best accomplished by monitoring feed intake, milk production, milk components and manure consistency. Depending on growing conditions, silage treated with fiber-technology inoculant may result in a change in digestibility.
A benefit of fiber-technology inoculant is increased forage rates, potentially increasing total daily starch loads with corn or cereal silages. Adjustments may be necessary for increased starch digestibility over time in storage between new- and old-crop feeds.
Make sure to follow up with cows expressing production problems when feeding fiber-technology silage. This is typically revealed in borderline levels for starch content or physically effective fiber. Fat depression and acidosis issues are quickly resolved by reducing grain—especially highly ruminally fermentable high-moisture corn – increasing forage inclusion rates or adding co-products that deliver sources of soluble fiber.
Many technological advances have directly impacted forages. Improvements in forage genetics and equipment throughout the industry have delivered significant gains in harvest efficiency. However, new developments in forage additives, such as fiber-technology inoculants, may be among the most innovative.
Source: Caitlyn Pool, progressivedairy.com