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Title 21

Displaying title 21, up to date as of 9/03/2026. Title 21 was last amended 8/31/2026.
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§ 520.90c Ampicillin boluses.

(a) Specifications. Each bolus contains ampicillin trihydrate equivalent to 400 milligrams of ampicillin.

(b) Sponsor. See No. 054771 in § 510.600(c) of this chapter.

(c) Related tolerances. See § 556.40 of this chapter.

(d) Conditions of use in nonruminating calves

(1) Amount. 5 milligrams per pound of body weight twice daily not to exceed 4 days.

(2) Indications for use. Oral treatment of bacterial enteritis (colibacillosis) caused by E. coli.

(3) Limitations. Treated calves must not be slaughtered for food during treatment and for 7 days after the last treatment. Federal law restricts this drug to use by or on the order of a licensed veterinarian.

[57 FR 37322, Aug. 18, 1992, as amended at 58 FR 61016, Nov. 19, 1993; 60 FR 55659, Nov. 2, 1995; 79 FR 28818, May 20, 2014. Redesignated and amended at 85 FR 18118, Apr. 1, 2020]