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Quality silage production pays for itself

Jim Sullivan and Bob Charley Published on 22 March 2010

The foundation of any dairy nutrition program is built around forages. Forages typically make up 40 to 60 percent of the ration dry matter (DM). Forage (silage) quality, whether good or poor, dictates what other ingredients need to be fed.

Silage quality is measured in many ways. In the past, we basically measured some crude nutrients (dry matter, crude protein, crude fiber, ash, etc.) and based silage quality on these numbers. Today, we have much more detailed measures of silage quality. Some of these include nutrients, like we used to measure, but with even more detail.



Instead of crude fiber, we can now measure fiber fractions (NDF, ADF, lignin, etc.) that give us an even better picture of the silage quality. In addition to nutrient fractions, we can also measure digestion of some of these nutrients. For example, NDF (neutral detergent fiber) is the major digestible fiber component in most feeds. We can now measure digestibility of the NDF, which we call NDFd. This gives us a better picture of how that fiber will be used by the cow. With silages, we can measure fermentation characteristics that tell us how well the silage fermented and how stable it is. We can also measure potential problems with molds, yeasts and mycotoxins.

Nutritionists typically build their rations around the forages (both quantity and quality) available. All cows have nutrient requirements that must be met for maximal health, reproduction and production. In addition to nutrient requirements, nutritionists also try to meet some physical characteristics of the ration (particle size, moisture, homogeneity, etc.).

Usually, dairies and their nutritionists do not have the luxury of choosing the silage they feed. Once the silage is put up, its quality is fixed and other ration ingredients need to be adjusted to meet ration requirements. Sometimes those requirements can be difficult to meet if the silage is of poor quality.

It is much easier and usually cheaper to balance rations when starting with high-quality silage. One example of this is the measurement mentioned earlier, NDFd (digestible fiber). An improvement in NDFd can have a dramatic effect on ration balancing and the resulting milk production obtained from that ration. According to the University of Wisconsin program, Milk 2006, which calculates milk per ton and milk per acre for different silages, an increase in NDFd can significantly impact milk production. For example, two different corn silages with the same level of NDF, fed at a typical rate of dry matter, with a difference in NDFd of 10 percentage points, could produce a milk production difference of over 2.5 pounds per cow per day. Back-calculating that to the value of the silage, that improvement in milk could translate into corn silage that was worth $10 per ton more than the silage at the lower NDFd. And that is not accounting for the savings in ration costs based on more costly inputs that would be needed with the poorer digestibility corn silage. Silage quality pays and it is important to pay attention to the details that are involved in making quality silage. From picking the right hybrids to harvest timing to chopping and packing, to feedout.

Here is a brief checklist of things to consider in producing quality silage.


Quality silage checklist

1. Preparation

  • Field and soil preparation
  • Fertilizer use and timing
  • Equipment and silo preparation and maintenance

2. Crop and variety selection

  • Suitable for the local conditions
  • Matches the goals of the overall feeding program

3. Harvest timing

  • Optimal stage of growth
  • Optimal level of plant moisture

4. Cutting and chopping

  • Cutting height
  • Optimum theoretical length of chop (TLC)
  • Processing (corn silage)

5. Inoculant

  • Scientifically proven to deliver desired results
  • Fermentation enhancement/aerobic stability
  • Product handling and applicator calibration

6. Filling and packing


  • Filling quickly
  • Progressive wedges (bunkers and piles)
  • Packing weight adequate for delivery rate
  • Adequate packing time (achieve a density of 15 pounds of dry matter per cubic foot)
  • Sealing silo quickly and effectively

7. Feedout

  • Rate adequate to prevent heating
  • Discard spoiled silage
  • Balance ration based on silage quality and quantity

It is important to work with a team including your nutritionist, agronomist, custom grower and custom harvester to determine the target levels for each of the above checklist items. They will be somewhat different depending on each dairy’s situation. It is important to have well-defined goals and targets and agreed-upon ways of monitoring and measuring those goals and targets.

As we discussed earlier, quality silage pays for itself in increased animal performance and decreased ration costs. A fair and equitable quality incentive program, that can be measured and agreed upon, is a good way to more likely meet your silage quality goals. Gains in milk production and/or reduction in ration costs can be used to pay for incentive programs. Incentive programs must be objective and should be in writing. Goals, with acceptable ranges, should be defined and should be within the control of the custom grower and custom harvester. Acts of nature that the grower or harvester cannot control or manage, should not be part of the incentive program.

Use forage analysis to determine baseline values for quality parameters like dry matter, protein content, starch content and fiber levels. Also, fermentation profiles can be used as an additional tool to determine quality and gauge silage management practices. In addition, digestibility measurements can be used with decision aids, like the University of Wisconsin’s MILK2006, to better guide pricing incentives for milk production potential from higher- quality forages.

Discounts for low quality can also be used. If the silage delivered is below certain agreed-on quality measures, the price per ton could be discounted. Premiums and discounts need to be measurable, achievable and realistic.

Make sure the contract and any incentives are related to feed value and quality. A long-term relationship between forage grower, the custom harvester and dairy producer, should be everyone’s goal. A win-win arrangement for everyone will go a long way toward ensuring a reliable supply of high-quality silage. PD

Jim Sullivan
  • Jim Sullivan

  • Dairy Tech
  • Service Manager
  • Lallemand Animal Nutrition
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