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Title 21

Displaying title 21, up to date as of 6/04/2026. Title 21 was last amended 6/03/2026.
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§ 520.2645 Tylvalosin.

(a) Specifications. Granules containing 62.5 percent tylvalosin (w/w) 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) Conditions of use in swine

(1) Amount. Administer 50 parts per million (ppm) tylvalosin continuously in drinking water for 5 consecutive days.

(2) Indications for use. For control of porcine proliferative enteropathy (PPE) associated with Lawsonia intracellularis infection in groups of swine intended for slaughter and female swine intended for breeding in buildings experiencing an outbreak of PPE; and for control of swine respiratory disease (SRD) associated with Bordetella bronchiseptica, Glaesserella (Haemophilus) parasuis, Pasteurella multocida, Streptococcus suis, and Mycoplasma hyopneumoniae in groups of swine intended for slaughter and female swine intended for breeding in buildings experiencing an outbreak of SRD.

(3) Limitations. Federal law restricts this drug to use by or on the order of a licensed veterinarian.

[77 FR 55415, Sept. 10, 2012, as amended at 83 FR 13635, Mar. 30, 2018; 86 FR 57997, Oct. 20, 2021; 89 FR 14410, Feb. 27, 2024]