At a recent meeting produced by Augusta Co-Op for dairy producers, representatives from Purina® Feeds summarized the latest trends in formulating dairy rations based on Rumen Degradable Starch. Based on a lot of research over the past 10-12 years, using Rumen Degradable Starch values versus Crude Starch has demonstrated advantages in milk production and component predictability.
1. There are no constants, only a lot of variability.
2. Rumen Degradable Starch (RDS) values, if known, can be utilized to improve rations.
3. Hybrid effects, growing conditions, harvest and storage management all contribute to RDS variability.
4. 2013 RDS values from corn silage will be different than the values for 2011 and 2012.
New Corn Silage Syndrome (NCSS)
One of the additional facts is that when crops are ensiled, the value of RDS increases the longer the crop is in storage. This is now known as New Corn Silage Syndrome and applies to all high moisture ensiled corn products.
The magic number of days in storage before RDS values tend to maximize is 30-60 days. So, the ideal would be to not have to feed new corn silage or high moisture grains for at least 60 days after ensiling. If you cannot do this for the 2013 crop, it might be a good year to put up a couple of extra bags this fall, so you can do it next fall.
Other methods used to mitigate NCSS are to:
1. Adjust the rumen degradable starch content to provide more available starch from other starch-containing ingredients. Substituting milo for corn has shown some benefit.
2. As mentioned in the September 2012 Production Notes, the use of liquid sugar also can replace some dietary starch and also reduce ration costs. A sugar content of between 5 - 7.5% of total dry matter is the goal. Augusta Co-Op markets liquid sugar products manufactured by Quality Liquid Feeds (QLF®).
For more options to improve the RDS levels in your milking ration, contact an Augusta Co-Op nutritionist.