Increasing feed costs are leading many producers to consider the use of alternative or local feed ingredients, even with their drawbacks such as anti-nutritional factors or increased presence of indigestible non-starch polysaccharides (NSPs). Fortunately, there are many enzyme feed additive products on the market today that can address these problems. With an abundance of available products, identifying the best product for your needs can be overwhelming. When you have determined the problem you need solved, and the category of enzyme that is required, (i.e. xylanase, glucanase), ask yourself the following questions to help narrow down the possibilities:

  • What are the product characteristics most important to evaluate?
  • How does a product perform in relevant trials?
  • What technical information is available about the product?

Key Considerations

  1. Product Characteristics

The easiest factor to consider is enzyme activity (refer to our December blog for detailed information on understanding enzyme units). While enzyme units can indicate the level of activity of a feed additive enzyme product, manufacturers also provide other important measures of biochemical performance. Ask these questions when reviewing biochemical performance information:

  • What is the thermostability of this product?
  • What type of substrate is ideal for this product?
  • Which feed ingredients am I using that are relevant to this product?
  • What is the matrix value of the product?

Further technical information, beyond performance measures, are useful in determining how you can use a product. For example, the matrix value of an enzyme is important information, especially in the case of evaluating NSPases. NSPases function to release additional energy from a diet, causing an uplift effect in total metabolizable energy. Based on performance trial data, the matrix value is determined for feed additive enzymes. This matrix value is generally published by the enzyme manufacturer with other product information. Because the matrix value is derived from animal trial data, it has a direct correlation with in vivo performance. Comparing feed additive enzymes based on matrix value is a predictable metric for animal performance.

  1. Research Trial Data

The most important consideration in selecting an enzyme feed additive is always efficacy. How does a product perform when utilized in a feeding trial? Apart from actually performing a trial, you can look to manufacturers’ trial summaries and research articles published in peer-reviewed journals. Enzyme manufacturers perform a number of trials on each enzyme feed additive, and collaborate in additional research trials conducted by independent academic institutions, providing trial data on critical performance factors. Trial summaries can be a great tool to evaluate enzyme performance prior to performing your own commercial trial. When reviewing this type of information, ask these questions to ensure the trial is relevant to your situation:

  • Were primary feed ingredients I use present in the trial?
  • Was the trial designed properly? (see our January & February blogs for more information)
  • What performance parameters were measured? (i.e. include body weight gain, feed intake, feed conversion ratio)
  • What energy savings does the product provide? (available metabolizable energy (AME), ileal digestible energy (IDE))

Both AME and IDE are useful approximations of the increased energy utilized by the bird, thus indicating the energy that can be saved in formulation. Energy savings are also a valuable means for comparing enzymes, especially when considering a carbohydrase enzyme product.

  1. Technical Support

Some enzyme manufacturers offer additional tools and/or services to aid in testing their product and for its long term use. Diet formulation is an important service that can be provided. A properly formulated diet will take full advantage of the benefits an enzyme feed additive can offer, such as increased digestibility, thus decreasing the energy required in a diet. A matrix value calculator is also a useful tool that can be offered to aid in the proper formulation of a diet. Always consider the services and tools an enzyme manufacturer has available!


In summary, an exact comparison between enzymes is difficult, due to the differing nature of biochemical characterization and animal trial designs. The only real and reliable method which takes into account all possible variables impacting performance, is an evaluation of the product in the producer’s own facilities. Producers should be thorough and thoughtful when selecting an enzyme to use in an animal feeding trial. However, certain metrics can be used as a guide for evaluating the options available. We recommend comparing feed additive enzymes based on certain characteristics, such as thermostability, animal trial reports (both manufacturer and academic), as well as technical information. This is the best available information, short of performing an animal trial in house.


References or further reading

  1. Ravindran, “Feed enzymes: The science, practice, and metabolic realities” J Appl Poult Res (2013) 22 (3): 628-636 doi:10.3382/japr.2013-00739

“Improving Animal Nutrition with Enzymes.”

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