NUTRITION
PIH-73
pork industry handbook
COOPERATIVE EXTENSION SERVICE • PURDUE UNIVERSITY • WEST LAFAYETTE, INDIANA
High-Moisture Grains for Swine
Authors
Jerry Hawton, University of Minnesota
Dave Bache, Purdue University
Bruce McKenzie, Purdue University
Reviewers
B. J. Caldwell, Forest, IN
H. William Newland, Ohio State University
Harold H. Hodson, Jr., Makanda, IL
Each year interest increases in storing high-moisture grain for livestock feeding. Originally, a shift toward more field shelling instead of picking ear corn may have brought this interest about because shelled corn must be mechanically dried in most instances for safe storage whereas ear corn can be safely stored at moisture contents up to 24% without drying. More recently, the concern has been in saving fuel. It takes approximately one gallon of propane fuel/4 1/2-6 bu. and one kilowatt hour of electricity/10-12 bu. with conventional high temperature drying to reduce the moisture content of wet grain ten percentage units (i.e., to dry from 25% down to 15% moisture). The prospect of fuel shortages and the near certainty of higher fuel costs plus the fact that many drying systems are pressed to keep pace with modern harvesting equipment are added reasons for interest in high-moisture grain. Also, with some cereal grains, earlier harvesting at higher moisture content results in reduced field losses and extra time to facilitate fall plowing in the north and seeding of a second crop further south.

Swine producers have centered their interest around high-moisture corn, sorghum (milo) and, to a much lesser extent, barley and wheat. High-moisture cereal grains can be successfully used in a swine feeding program. However, special consideration must be given to proper storage and feeding to realize maximum performance from its use.

Storage Methods
When ensiling high-moisture grain, you must store it in an oxygen-free environment to prevent spoilage. Proper ensiling or fermentation depends upon the percent of moisture in the grain. The ideal moisture content to ensile wet grain for swine appears to be in the 22-28% range. Moisture content over 28% leads to a greater fermentation, resulting in more acid production, which tends to be less palatable to the pig. On the other hand, the fermentation of grain containing less than 22% moisture is relatively slow,
and the amount of acid produced may not be sufficient to kill those organisms that cause spoilage. This fact is especially true when oxygen (even in small amounts) can penetrate the grain mass. It should be pointed out, though, that type of storage has little effect upon spores or toxin already incorporated into the grain prior to storage.

There are three basic storage methods for high-moisture grains: (1) ensiling in sealed (airtight) storage, (2) ensiling in non-sealed storage, and (3) preservation with organic acid treatment. High-moisture cereal grains properly handled and stored using any one of these methods will provide a suitable swine feed.

Sealed Storage
High-moisture grain can be stored in specially constructed oxygen-limiting silos which operate by restricting the entry and exchange of air (oxygen is the important gas) into the storage. It is not necessary to crack or grind the grains before storing in this manner. Another characteristic of sealed storage is that it can be unloaded from the bottom. With whole shelled corn, the grain flows from the top surface into a funnel of withdrawal and down a center flow stream to the bottom outlet where it is usually augered to the outside.

Many hog producers invest in sealed storage (oxygen-limiting) facilities because they expect improvement in feed conversion and other performance measures. However, when compared on an equal dry matter basis, the data on high-moisture grains stored in sealed storage will not support claims of improved efficiency or growth rate in swine when compared with rations based on dry grains.

Sealed storage is the most popular method of storing high-moisture grains even though greater initial capital investment is required. This type of storage offers increased handling ease and reliability over non-sealed alternatives and eliminates the 2-5% spoilage loss normally associated with well-managed, unsealed systems.
Cooperative Extension Work in Agriculture and Home Economics, State of Indiana, Purdue University and U.S. Department of Agriculture Cooperating. H. G. Diesslin, Director, West Lafayette, Ind. Issued in furtherance of the Acts of May 8 and June 30, 1914. It is the policy of the Cooperative Extension Service of Purdue University that all persons shall have equal opportunity and access to its programs and facilities without regard to race, religion, color, sex or national origin.