StacksVerified U.S. regulatory reference

21 CFR §558.274

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
  1. (a)Specifications. Type A medicated articles containing 2.4 or 8 grams hygromycin B per pound (g/lb).
  2. (b)Sponsor. See No. 058198 in § 510.600(c) of this chapter for as follows:
  3. (c)Related tolerances. See § 556.330 of this chapter.
  4. (d)Special considerations.
    1. (1)Federal law restricts medicated feed containing this veterinary feed directive (VFD) drug to use by or on the order of a licensed veterinarian. See § 558.6 for additional requirements.
    2. (2)The expiration date of VFDs for hygromycin B medicated feeds must not exceed 6 months from the date of issuance. VFDs for hygromycin B shall not be refilled.
  5. (e)Conditions of use. It is used in feed as follows:
    1. (1)Chickens—
    2. (2)Swine—