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Title 21

Displaying title 21, up to date as of 6/12/2026. Title 21 was last amended 6/11/2026.
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§ 522.850 Estradiol valerate and norgestomet in combination.

(a) Specifications. The product is a two-component drug consisting of the following:

(1) An implant containing 6.0 milligrams of norgestomet.

(2) An injectable solution (sesame oil) containing 3.0 milligrams of norgestomet and 5.0 milligrams of estradiol valerate per 2 milliliters.

(b) Sponsor. See 000010 in § 510.600(c) of this chapter.

(c) Related tolerances. See § 556.240 of this chapter.

(d) Conditions of use

(1) Amount. One implant and 2 milliliters of injection at time of implantation.

(2) Indications for use. For synchronization of estrus/ovulation in cycling beef cattle and non-lactating dairy heifers.

(3) Limitations. Insert implant subcutaneously in the ear only; then immediately inject solution intramuscularly only. Counting the day of implantation as day 1, remove the implant on day 10. Collect all implants as they are removed and burn them. While animals are restrained for artificial insemination, avoid other treatments such as vaccinations, dipping, pour-on grub and louse prevention, spraying, etc. When inseminating without estrus detection, the entire treated group should be started at 48 hours after the last implant has been removed and should be completed within 6 hours. Where estrus detection is preferred, insemination should be approximately 12 hours after first detection of estrus. Those that do not conceive can be re-bred when they return to estrus approximately 17 to 25 days after implant removal. Do not use in cows producing milk for human consumption.

[47 FR 55477, Dec. 10, 1982, as amended at 48 FR 49656, Oct. 27, 1983; 51 FR 33592, Sept. 22, 1986; 54 FR 1165, Jan. 12, 1989; 84 FR 39184, Aug. 9, 2019; 84 FR 32992, July 11, 2019]