Byproducts…. Is there ever a catch?

One thing that always amazes me during my travels to dairy farms both in the state of Nebraska as well as other parts of the world is the sheer diversity of byproducts fed to dairy cattle. The byproducts originate for the food, beverage, bioenergy industries.  I personally have seen such unusual feeds as carrots, bread waste, cookie waste, cannery waste, and potato chips successfully used to feed dairy cattle. In general, byproducts are used in because through rumen fermentation, cattle are able to utilize both protein and energy out of a wide range of feed sources and convert them into a high value food product, namely milk. We, in Nebraska, are fortunate to be located near the corn milling industries, which produce feeds such as distillers grains and corn gluten feed. Research has demonstrated that these are high quality feeds and that the variability of chemical composition is low. Furthermore this feed can be easily transported and stored. Research out of Michigan State University has even shown that use of byproducts may reduce the amount of land to produce feed by as much as 51%! Every once in a while I receive a query from a dairy producer contemplating purchasing and feeding a “new” byproduct. In many cases these feeds can be purchased a lower costs than traditional commodities but producers should ask themselves a number of questions before the feed is delivered and used on the farm.


  1. What feed will this new byproduct replace and is the new feed economically worthwhile? This may seem like an obvious question but producers should ask themselves what feed or feeds with this new byproduct replace and does the cost of doing so make sense.
  2. Supply of the new byproduct?  Even if the new byproduct is economically attractive sometimes there is a seasonal effect on availability and producers should ask questions to make sure the supply of the new byproduct will meet their long range needs. In many cases in order for this to occur producers will need unique and special storage systems for these new byproducts
  3. Adequate and appropriate storage? When determining the supply of the new byproduct, it is important to consider your storage facilities, also.  Is there adequate space for the new byproduct ,and is the storage space appropriate for the byproduct?
  4. Variability in chemical composition? Obviously a decision to purchase any feed depends upon the chemical composition and the nutrients which it supplies but one feed test is not enough. byproducts may vary greatly in chemical composition and producers should ask the seller for information on how the chemical composition of the feed will change over time.
  5. Presence of anti-nutritional or toxic factors? Given that byproducts are secondary producers, there are cases in which these feeds contain problematic constituents. For example, peanut byproducts may contain mycotoxins, usually aflatoxins. Thus if considering this feed, it is recommended that producers obtain an analysis of aflatoxin content with each shipment to prevent possible aflatoxin poisoning of cattle.

One thing that does not seem likely is that byproducts will go away. But as industries change and new processing facilities pop up one thing is clear, the type of byproduct and even the chemical composition will change. Producers are encouraged to consider using new feeds to improve the bottom line but doing so should also take careful consideration and thought.