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New Animal Drugs For Use in Animal Feed; Zilpaterol

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Food and Drug Administration, HHS.


Final rule.


The Food and Drug Administration (FDA) is amending the animal drug regulations to reflect approval of a new animal drug application (NADA) filed by Intervet Inc. The NADA provides for use of approved, single-ingredient Type A medicated articles containing zilpaterol hydrochloride and melengestrol acetate in two-way combination Type B and Type C medicated feeds for heifers fed in confinement for slaughter.


This rule is effective March 31, 2008.

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Gerald L. Rushin, Center for Veterinary Medicine (HFV-126), Food and Drug Administration, 7500 Standish Pl., Rockville, MD 20855, 240-276-8103, e-mail:

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Intervet Inc., P.O. Box 318, 29160 Intervet Lane, Millsboro, DE 19966, filed NADA 141-284 that provides for use of ZILMAX (zilpaterol hydrochloride) and MGA (melengestrol acetate) Type A medicated articles to make dry and liquid two-way combination Type B and Type C medicated feeds used for increased rate of weight gain, improved feed efficiency, and increased carcass leanness; and for suppression of estrus (heat) in heifers fed in confinement for slaughter during the last 20 to 40 days on feed. The NADA is approved as of February 29, 2008, and the regulations in 21 CFR 558.665 are amended to reflect the approval.

In accordance with the freedom of information provisions of 21 CFR part 20 and 21 CFR 514.11(e)(2)(ii), a summary of safety and effectiveness data and information submitted to support approval of this application may be seen in the Division of Dockets Management (HFA-305), Food and Drug Administration, 5630 Fishers Lane, rm. 1061, Rockville, MD 20852, between 9 a.m. and 4 p.m., Monday through Friday.

The agency has determined under 21 CFR 25.33(a)(2) that this action is of a type that does not individually or cumulatively have a significant effect on the human environment. Therefore, Start Printed Page 16755neither an environmental assessment nor environmental impact statement is required.

This rule does not meet the definition of “rule” in 5 U.S.C. 804(3)(A) because it is a rule of “particular applicability.” Therefore, it is not subject to the congressional review requirements in 5 U.S.C. 801-808.

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List of Subjects in 21 CFR Part 558

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Therefore, under the Federal Food, Drug, and Cosmetic Act and under the authority delegated to the Commissioner of Food and Drugs and redelegated to the Center for Veterinary Medicine,

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1. The authority citation for

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Authority: 21 U.S.C. 360b, 371.

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2. In § 558.665, add paragraph (e)(2) to read as follows:

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(e) * * *

Zilpaterol in grams/tonCombination in grams/tonIndications for useLimitationsSponsor
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(2) 6.8 to provide 60 to 90 mg/head/dayMelengestrol acetate to provide 0.25 to 0.5 mg/ head/dayHeifers fed in confinement for slaughter: As in paragraph (e)(1) of this section; and for suppression of estrus (heat).As in paragraph (e)(1) of this section; see paragraph §§ 558.342(d) of this chapter. Melengestrol acetate as provided by No. 000009 in § 510.600(c) of this chapter.057926
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Dated: March 21, 2008.

Bernadette Dunham,

Director, Center for Veterinary Medicine.

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[FR Doc. E8-6601 Filed 3-28-08; 8:45 am]