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Title 21

Displaying title 21, up to date as of 6/05/2026. Title 21 was last amended 6/05/2026.
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§ 558.555 Semduramicin.

(a) Specifications. Type A medicated article containing:

(1) 22.7 grams (g) per pound (lb) (50 g/kilogram (kg)) semduramicin (as semduramicin sodium).

(2) 22.7 g/lb (50 g/kg) semduramicin (as semduramicin sodium biomass).

(b) Sponsor. See No. 066104 in § 510.600(c) of this chapter for use of product described in paragraph (a)(1) of this section as in paragraph (d) of this section; for use of product described in paragraph (a)(2) of this section as in paragraph (e) of this section.

(c) Related tolerances. See § 556.597 of this chapter.

(d) Conditions of use in chickens. It is used in chicken feed as follows:

Semduramicin in grams per ton Combinations in grams per ton Indications for use Limitations Sponsor
(1) 22.7 (25 ppm) Broiler chickens: For the prevention of coccidiosis caused by Eimeria acervulina, E. brunetti, E. maxima, E. mivati/E. mitis, E. necatrix, and E. tenella. Do not feed to laying hens. 066104
(2) 22.7 Bacitracin methylenedisalicylate 10 to 50 Broiler chickens: As in paragraph (d)(1) of this section; for improved feed efficiency. Feed continuously as sole ration. Do not feed to laying hens. Bacitracin methylenedisalicylate as provided by No. 054771 in § 510.600(c) of this chapter. 066104

(e) Conditions of use in chickens. It is used in chicken feed as follows:

Semduramicin in grams per ton Combination in grams per ton Indications for use Limitations Sponsor
(1) 22.7 (25 ppm) Broiler chickens: For the prevention of coccidiosis caused by Eimeria tenella, E. acervulina, E. maxima, E. brunetti, E. necatrix, and E. mitis. Do not feed to laying hens. 066104
(2) [Reserved]

(f) Semduramicin may also be used in combination with virginiamycin as in § 558.635.

[59 FR 17477, Apr. 13, 1994, as amended at 60 FR 57928, Nov. 24, 1995; 61 FR 29481, June 11, 1996; 61 FR 43451, Aug. 23, 1996; 61 FR 66584, Dec. 18, 1996; 62 FR 66985, Dec. 23, 1997; 64 FR 48296, Sept. 3, 1999; 66 FR 47964, Sept. 17, 2001; 69 FR 13221, Mar. 22, 2004; 70 FR 41961, July 21, 2005; 73 FR 812, Jan. 4, 2008; 74 FR 41631, Aug. 18, 2009; 79 FR 10983, Feb. 27, 2014; 79 FR 13546, Mar. 11, 2014; 81 FR 17609, Mar. 30, 2016; 81 FR 95013, Dec. 27, 2016; 86 FR 14826, Mar. 19, 2021; 87 FR 17948, Mar. 29, 2022]