Hydrochloric acid can be added to feeds (e.g., Europeans have added it to grass silage at the time of ensiling as a direct acidifying agent). Commercial feed companies in the United States can add hydrochloric to by-product feeds to produce negative DCAD products to reduce the DCAD of close-up dry cow diets. The U.S. EPA regulates this process. The acid is very corrosive and dangerous to handle. We do not recommend adding hydrochloric acid to feeds or the total mixed ration (TMR) directly at the farm. Feed company products containing hydrochloric acid can be added to the TMR on-farm, but supplier guidelines should be followed closely.
Mike Hutjens, Extension Dairy Specialist, University of Illinois - Illini DairyNET
