Nutrivail^® Feed Technology

It refers to a portfolio of silage additives, Pioneer^® brand 11CFT, 11GFT, 11AFT, developed by Pioneer to deliver improved fiber digestibility in corn silage, grass/cereal and alfalfa silage, respectfully. These products each contain a novel, proprietary strain of Lactobacillus buchneri along with additional homofermentative Lactobacillus strain(s) unique to the crop-specific fermentation demands of each of these crops. The Lactobacillus buchneri strain in these products produce an enzyme to aid in fiber digestion and also improve bunklife by inhibiting yeast growth at feedout.

The Lactobacillus buchneri strain in NUTRIVAIL products produces specific esterase enzymes (ferulate and acetyl esterase) that release fiber polysaccharides from the lignin backbone. Decoupling polysaccharides (e.g. hemicellulose) from the lignin alters the thee-dimensional structure increasing access to the polysaccharides by rumen bacteria resulting in more rapid fiber digestion. Lignin is not degraded so levels in the forage remain the same and fiber fragility does not seem to be significantly reduced. Additionally, greater degradation of the polysaccharide fiber fraction is observed due to the removal of digestion inhibiting acetyl groups bound to the sugar components. Having bacteria produce these esterase enzymes, which are active at low silage pH’s, is a much more economical and practical approach than the addition of high levels of commercial enzyme products.

Current NIR calibrations and commonly available in vitro (test tube) methods do not have the sensitivity to predict the NDFD and digestion rate (Kd) improvements that have been proven with in vivo (live animal) feeding trials. Nutrivail products produce enzymes which cause physio-chemical changes in the fiber-lignin linkages, while not actually changing the amount of lignin or fiber in the silage. Rumen bacteria recognize this change and digest the decoupled fiber at a faster rate and often greater extent. In vivo experiments have consistently detected changes in fiber digestibility, as do in situ methods (replicated, 6mm-ground samples placed in nylon bags and hung in fistulated animals). Labs utilizing gas-production methods (e.g. Fermentrics^®) have been able to detect the effects of Nutrivail in modifying carbohydrate pool (e.g. B1, B2 and B3) digestion rates. This allows nutritionists to adjust rations and reduce protein or concentrate supplementation based on Nutrivail-altered B-pool digestion rates.

From the many animal experiments and field trials conducted by Pioneer and University cooperators, a 4-percentage point increase in 48-hour NDFD (over baseline NDFD estimates) is a reasonable starting point to factor in the effect of Nutrivail-silages. However, most approaches that use single, time-point NDFD values in summative equations to predict NE-L (e.g. NRC or UWMILK2006) does not appear adequately sensitive to the digestion rate changes resulting from treating silages with Nutrivail products.

Changes in the digestion rates (Kd) of the B3 (NDF) carbohydrate pool can be modified automatically in formulation models, using Cornell Model logic such as NDS or AMTS, from single, time-point NDFD values or by manually inserting calculated Kd values, such as NDF Kd (VanAmburgh) or MIR_P1 (Mertens), found on many forage analyses reports. However, field experience suggests that calculated Kd rates may not fully account for the effect of Nutrivail products. A preferred alternative is to directly measure digestion rates using the gas-production method, Fermentrics^®. Fermentrics analysis of Nutrivail-silages suggests 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. While it is preferred to directly measure the B-pool digestion rates with Fermentrics, if this is not possible or if digestion rates are not available on laboratory reports, Fermentrics analyses have shown that the B- pool carbohydrate rates are increased, on average, by the amount shown in the table below (example: 11CFT-corn silage feed library B3 rate of 3.4%/ hour should be increased by 35% to 4.6%/hour).

1. There is no problem with feeding Nutrivail-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.
2. Cows should be monitored and the diet gradually modified to account for the changes in rate and extent of fiber digestibility in Nutrivail-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 Nutrivail inoculant, may result in higher, similar or lower digestibility compared to old- crop. Typically, the increase in fiber digestion rates will be greater in forages grown in environments conducive to low fiber digestion (e.g. wet, hot conditions).
3. Feeding Nutrivail-silage typically allows for reduction in both “fast pool” nutrients (e.g. starch) and protein (from increased microbial protein production). In practice, this means reducing grain and protein in the TMR to offset increased availability of fiber components and the shifting of “slow pool” nutrients (B3) to the “fast pools” (B1 and B2). 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 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 Nutrivail-silage.
4. A starting point for concentrate removal when feeding NUTRIVAIL- treated cereal, grass or legumes silage at typical rates of 60 lbs/cow/day (as fed or 21 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 Nutrivail-silage.
5. 11CFT-treated corn silage will not typically increase dry matter intake of the entire TMR like what is commonly observed when feeding BMR corn silage. BMR corn silage has significantly less lignin bound to hemicellulose and the theory is that this increases fiber fragility allowing for more rapid escape from the rumen resulting in higher DM intakes. 11CFT-treated corn silage has the same amount of lignin as non-BMR corn silage thus the benefits of Nutrivail silage is allowing rumen bacteria more rapid access to fiber polysaccharides given the action of esterase enzyme on the lignin cross-linkages which inhibit NDF digestion. Because of the reduced cross-linking of lignin and hemicellulose in BMR, it is generally not advised to use 11CFT on BMR; but rather use Pioneer^® brand 11C33 to inoculate BMR corn silages.
6. Field experience with herds who observed milkfat depression problems when feeding Nutrivail-silage, were typically borderline for effective fiber and/or acidosis issues and quickly resolved the problem (and lowered feed costs) by reducing grain (especially high-moisture corn), increasing silage inclusion rates (and effective fiber) and/or adding co-products such as soy hulls (additional source of soluble fiber). Increased inclusion rate of dietary corn silage is a benefit of Nutrivail-silage, but this may also increase total daily load of highly ruminally fermentable starch from Nutrivail- treated corn or cereal silages. As with any corn silage, adjustments will also be necessary for increased starch digestibility over time in storage between new-crop and old crop feeds.
7. When feeding high levels of highly digestible forages (corn silage, grass or legumes), it is helpful to frequently monitor cud-chewing, TMR particle size consistency and sorting issues due to changes in TMR mixing/delivery, along with ensuring adequate levels of dietary NDF and peNDF (>23%). The peNDF or fragility of fiber in Nutrivail- silage appears like that of conventional corn silages. As with any ration, observing animal performance, intakes, effective fiber levels, and manure consistency will help nutritionists further refine Nutrivail-silage-based rations.