[Code of Federal Regulations] [Title 21, Volume 6] [Revised as of January 1, 2003] From the U.S. Government Printing Office via GPO Access [CITE: 21CFR573.225] [Page 500] TITLE 21--FOOD AND DRUGS CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) PART 573--FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS--Table of Contents Subpart B--Food Additive Listing Sec. 573.225 1,3-Butylene glycol. The food additive 1,3-butylene glycol (1,3-butanediol) may be safely used in accordance with the following prescribed conditions: (a) It complies with the specifications in Sec. 173.220(a) of this chapter. (b) It is intended for use in swine feed as a source of energy. (c) It is to be thoroughly mixed into feed at levels not to exceed 9 percent of the dry matter of the total ration. (d) 1,3-Butylene glycol should be mixed in feed with equipment adapted for the addition of liquids, and the feed should be mixed not less than 5 minutes after its addition. [53 FR 40061, Oct. 13, 1988]