Fiber Technology Feeding Guidelines
- The proprietary Lactobacillus buchneri strain in Pioneer® brand Fiber Technology (FT) inoculants produces specific enzymes (ferulate and acetyl esterase) as it grows in the silage mass. These enzymes attack the ester bond linking cell wall polysaccharides to indigestible lignin resulting in more rapid fiber digestion by rumen bacteria.
- There is no problem with feeding FT-treated silages immediately upon ensiling, but the full benefit of the enzyme activity will not be realized until the silage has fermented for 60 days.
- Nutritionists should balance diets containing new-crop forages and ensiled grains using standard lab analyses and their normal ration formulation approach without any considerations for the effect of FT inoculants. This will allow time to stabilize the diet and address the major differences in NDFD, starch content and/or starch digestion rates in the new-crop compared to the old-crop silages.
- The FT inoculant benefit of increased fiber digestibility and higher rumen bacterial populations (bypass protein source) allows for the fine-tuning of the diet and the possible removal of some grain and protein. Dry matter intake will not be significantly increased as is the case with reduced lignin crops like BMR corn silage or sorghum. Lignin levels and fiber fragility (effective fiber effect) will be similar between normal silages and those inoculated with FT inoculants.
When software allows for digestion rate changes
- Some ration balancing programs allow for modifying the digestion rates (Kd) of the B-pool carbohydrate fractions of feedstuffs: B1 (starch), B2 (soluble fiber) and B3 (NDF). Rather than using book values, nutritionists can fine-tune diets and potentially reduce concentrate and protein supplementation (depending upon the digestion kinetics of the previous-years forage crops) by adjusting these rates due to the effect of FT-inoculants on the B-pool carbohydrates.
- B3 digestion rates, calculated from NDF, lignin and single, time-point NDFD values, are reported on many laboratory forage analyses by employing the VanAmburgh Rate Calculator (available as a spreadsheet from the laboratory or from DuPont Pioneer (email@example.com)).
- A preliminary starting point for modifying the B3 digestion rate for the effect of FT-inoculants is to increase the 48-hr NDFD value by 4 percentage points and input the newly calculated B3 digestion rate value into the ration program feed table. However, field experience suggests that increasing B3 rates by 15-20%, (which the VanAmburgh spreadsheet predicts from a 4-percentage point increase in NDFD), will not fully account for the effect of FT products on the B3 fraction nor adjust for increased rates of the B1 (starch) and B2 (soluble fiber). Analysis of FT-silages suggest that when cell wall components are decoupled from lignin, their rates of digestion begin to approach that of faster digesting carbohydrates such as soluble fiber or starch requiring that the rates of B1 and B2 pools also be modified in FT-silages.
- Current NIR or wet chemistry fiber digestion methods do not have the sensitivity to predict the digestion rate increases that have been proven in animal research trials with FT-inoculants. Fermentrics™ analysis system is a sophisticated gas-production lab method available through Dairyland Laboratories which has proven capable of measuring the increase in B1, B2 and B3 digestion rates as a result of the enzyme activity of FT inoculants.
- A Fermentrics analysis of the FT-treated silage after 2-months of fermentation along with the newly rebalanced lactating diet should be helpful in further adjusting rates and inclusion levels of supplemental protein and grain.
- It is preferred to directly measure the B-pool digestion rates with a Fermentrics analysis, however, hundreds of Fermentrics analyses has shown that the B-pool carbohydrate rates are increased, on average, by the amount shown in the table below (example: FT-corn silage book value B3 rate of 3.4%/hour should be increased by 35% to 4.6%/hour). Adjusting book values upwards by these percentages is a possible approach, but only if the feed library B-pool rates approximate the true rates of the forage (which is unlikely given the huge growing environment impact on carbohydrate digestion rates).
|Table 1. Expected increase in B-pool digestion rates due to FT inoculant activity
When software does not allow for digestion rate changes
- Cows should be monitored and the diet gradually modified to account for the changes in rate and extent of fiber digestibility in FT-silages compared to old-crop silages. This is best accomplished by monitoring feed intake, milk production, milk components and manure consistency. Depending on growing condition influence, new-crop silage treated with FT-inoculant, may result in higher, similar or lower digestibility compared to old-crop.
- Field experience has demonstrated that Pioneer® inoculant 11CFT-treated corn silage being fed at a typical inclusion rate of 50 lbs of corn silage/cow/day (as fed or @35% DM, 17.5 lbs DM/cow/day), allows producers to remove about 2 lbs of corn meal (as fed) and 0.75 lbs of 44% crude protein soybean meal (as fed) without any change in cow production or body condition (corn silage or other forage inclusion can be increased to offset the removal of grain and protein). These amounts can be adjusted up/down based on higher or lower ration inclusion rates of FT-silage.
- A starting point for concentrate removal when feeding FT-treated cereal, grass or legumes silage at typical rates of 35 lbs/cow/day (as fed or @55% DM 19.2 lbs DM/cow/day), is about 0.5 lbs of 44% crude protein meal (as fed) and 0.2 lbs of corn meal (as fed). These amounts can be adjusted up/down based on higher or lower ration inclusion rates of FT-silage.
- Increased inclusion rate of forages is a benefit of FT-silages, potentially increasing total daily starch loads with FT-treated corn or cereal silages. Adjustments will also be necessary for increased starch digestibility over time in storage between new-crop and old crop feeds.
- Follow-up with herds expressing production problems when feeding FT-silage typically revealed borderline levels for starch content and/or physically effective fiber. Fat depression and acidosis issues were quickly resolved by reducing grain (especially highly ruminally fermentable high-moisture corn), increasing forage inclusion rates (and effective fiber) and/or adding co-products that delivered sources of soluble fiber.