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).
11CFT/11GFT | 11AFT | |
---|---|---|
B1 | 50% | 60% |
B3 | 35% | 20% |
Pioneer® brand products are provided subject to the terms and conditions of purchase which are part of the labeling and purchase documents.