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Title 21

Displaying title 21, up to date as of 6/16/2026. Title 21 was last amended 6/15/2026.
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§ 558.633 Tylvalosin.

(a) Specifications. Type A medicated articles containing 77.12 grams tylvalosin per pound as tylvalosin tartrate.

(b) Sponsor. See No. 066916 in § 510.600(c) of this chapter.

(c) Related tolerances. See § 556.748 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 for additional requirements.

(2) VFDs for tylvalosin shall not be refilled.

(3) Crumbled Type C medicated feeds must bear an expiration date of 7 days after the date of manufacture.

(e) Conditions of use.

Tylvalosin in
grams/ton
Indications for use Limitations Sponsor
(i) 38.6 Swine: For the control of porcine proliferative enteropathy (PPE) associated with Lawsonia intracellularis infection in groups of swine in buildings experiencing an outbreak of PPE. Feed continuously as the sole ration for 14 consecutive days. 066916
(ii) [Reserved]

[81 FR 36790, June 8, 2016, as amended at 81 FR 67153, Sept. 30, 2016; 84 FR 12504, Apr. 2, 2019; 87 FR 17948, Mar. 29, 2022; 87 FR 58968, Sept. 29, 2022]