---
kind: "section"
citation: "21 C.F.R. § 558.274"
title: "21"
number: "558.274"
heading: "Hygromycin B."
url: "https://uscodex.org/cfr/21/558.274"
---

# §558.274. Hygromycin B.

- (a) **Specifications.** Type A medicated articles containing 2.4 or 8 grams hygromycin B per pound (g/lb).
- (b) **Sponsor.** See No. 058198 in [§ 510.600(c)](/cfr/21/510.600.md?p=c) of this chapter for as follows:
- (c) **Related tolerances.** See [§ 556.330](/cfr/21/556.330.md) of this chapter.
- (d) **Special considerations.**
  - (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](/cfr/21/558.6.md) for additional requirements.
  - (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.
- (e) **Conditions of use.** It is used in feed as follows:
  - (1) **Chickens—**
  - (2) **Swine—**

## Notes

### Amendments

[81 FR 95005, Dec. 27, 2016]

### Authority

Authority: 21 U.S.C. 354, 360b, 360ccc, 360ccc-1, 371.

### Source

Source: 40 FR 13959, Mar. 27, 1975, unless otherwise noted.

### Amendments

[81 FR 95005, Dec. 27, 2016]