Why the Alltech® In Vitro Fermentation Model?
The Alltech® In Vitro Fermentation Model (IFM) is a support tool for nutritionists to evaluate and troubleshoot rations in order to maximize feed efficiency and reduce ever-rising feed costs.
Nutritionists rely on nutritional models and chemical feed characteristics to formulate diets. However, this information is static and does not provide a complete evaluation of nutrient availability. Alltech IFM is a dynamic diagnostic tool that measures the digestion of feed in the rumen in real time. This allows us to get a comprehensive view of feed digestion as opposed to a snapshot from a single point in time.
What is Alltech IFM?
Alltech IFM simulates rumen fermentation to evaluate the energy and protein availability of feeds. This technique is based on measuring gas production from microbial digestion as a proxy for real-time digestion. Since we continuously measure gas production, we are able to separate the energy contribution of feed ingredients by the rate of digestion. We can describe how much and at what rate carbohydrates from quickly degrading sources (e.g., starches and sugars) and slowly degrading sources (e.g., fiber) are contributing to the balance of the ration. We also measure microbial biomass to indicate protein availability and protein-to-energy balance in the ration. Alltech IFM analysis also includes a basic wet chemistry to provide a complete picture of the feed sample.
How does it work?
Feed samples are incubated using rumen fluid and a buffer system to mimic natural rumen fermentation in the animal. As digestion progresses, volumes of fermentation gases, such as methane and carbon dioxide, are continuously monitored using an automated system.
- Alltech IFM measures gas production, taking into account all nutrients fermented (solubles and insolubles). Total gas production is separated into quickly and slowly fermenting carbohydrates using mathematical equations.
- Estimates of rates of degradation of the different carbohydrate fractions provide additional information on the nutritive value of the feed.
- Measurement of fermentation byproducts includes:
- Yield of microbial biomass (i.e., source of metabolizable protein to the animal).
- Volatile fatty acid profile (i.e., source of energy to the animal).
- Total gas production.
- In vitro dry matter digestibility.
Alltech IFM applications:
- Nutritional tool to optimize ruminal function, ruminal starch availability and fiber digestion in the rumen, and protein balance.
- Single test provides more accurate, informed recommendations to optimize feed in a relatively short period of time and at low cost.
- Troubleshoot potential problems and develop supplementation strategies to optimize feed efficiency and profitability, which are tailored to the customer’s feeding programs.
- Estimates of gas production can help identify total mixed rations that are less efficient and that produce excessive gas per unit of dry matter digested. Ingredient and chemical composition are evaluated in conjunction with gas pool sizes to identify sources of potential problems.
Frequently asked questions:
- What types of samples do you recommend submitting?
- We focus on total mixed rations in order to characterize what the animal is eating. The individual ingredients included in a total mixed ration will have associative effects on the digestion of the ration as a whole that cannot be determined based on individual analysis. However, analyzing individual ingredients can be useful in the case of forages, especially corn silage and hay. Alltech IFM results will give you the information to evaluate the forage quality, for example, if you need to choose between multiple bunkers of corn silage or decide whether to buy a lot of hay.
- What is the effect of particle size on Alltech IFM results?
- On receipt of the feed sample in the lab, we dry and grind the sample to prepare it for analysis. This provides us with a consistent sample. It also removes the effect of particle size from the results. However, we test the potential digestibility of the nutrients in the ration and can determine if digestibility issues are a function of chemical or physical form. If the ration is potentially digestible based on Alltech IFM results but you are seeing undigested feed in feces, reducing the particle size of the feed may be the solution. If the potential digestibility of the ration is low due to the chemical makeup of the ration (e.g., due to resistant starch), particle size is likely not the culprit and feed additives such as enzymes or live yeast may provide the solution.
- How will the source of rumen fluid affect Alltech IFM results?
- We obtain rumen fluid from a fistulated lactating Holstein that is fed a high-producing lactation ration (corn silage, corn grain, soybean meal). While this cow has a different microbial population that your customers’ cows, the results obtained will be applicable to any herd. We maintain standard operating procedures and do quality control for every Alltech IFM test we conduct. The reference ranges we have developed in our lab allow us to compare rations and make recommendations based on relative comparisons that will be applicable across rations.
- Can samples be frozen?
- If you cannot ship samples right away, you can store them in the refrigerator or freezer.
- How much sample should be sent?
- Collect enough total mixed ration sample to fill a 1-gallon plastic bag (about 2 pounds per 1 kilogram).