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Code · CFR · Title 21 — Food and Drugs · Part 558 — New Animal Drugs for Use in Animal Feeds · § 558.68

§ 558.68. Avilamycin.

936 words·~4 min read·/us/cfr/t21/s§ 558.68·

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(a)Specifications. Each pound of Type A medicated article contains 45.4 or 90.7 grams of avilamycin.
(b)Sponsor. See No. 058198 in § 510.600(c) of this chapter.
(c)Related tolerances. See § 556.60 of this chapter.
(d)Special considerations.
(1)Federal law restricts medicated feed containing this veterinary feed directive
(VFD)drug to use by or on the order of a licensed veterinarian. See § 558.6 for additional requirements.
(2)The expiration date of VFDs for avilamycin medicated feeds must not exceed 90 days from the date of issuance. VFDs for avilamycin shall not be refilled.
(e)Conditions of use. Administer in feed as follows:
(1)Chickens— Avilamycin in grams/ton Combination in grams/ton Indications for use Limitations Sponsor
(i)13.6 to 40.9Broiler chickens: For the prevention of mortality caused by necrotic enteritis associated with Clostridium perfringens in broiler chickensFeed as the sole ration for 21 consecutive days. To assure responsible antimicrobial drug use in broiler chickens, treatment administration must begin on or before 18 days of age058198
(ii)13.6 to 40.9Monensin, 90 to 110Broiler chickens: For the prevention of mortality caused by necrotic enteritis associated with Clostridium perfringens, and as an aid in the prevention of coccidiosis caused by Eimeria necatrix, E. tenella, E. acervulina, E. brunetti, E. mivati, and E. maximaFeed as the sole ration for 21 consecutive days. Feed to chickens that are at risk of developing, but not yet showing clinical signs of, necrotic enteritis associated with Clostridium perfringens. To assure responsible antimicrobial drug use in broiler chickens, treatment administration must begin on or before 18 days of age. Monensin as provided by Nos. 016592 or 058198 in § 510.600(c) of this chapter. See § 558.355(d)016592 058198
(iii)13.6 to 40.9Narasin, 54 to 90Broiler chickens: For the prevention of mortality caused by necrotic enteritis associated with Clostridium perfringens; and for the prevention of coccidiosis caused by Eimeria necatrix, E. tenella, E. acervulina, E. brunetti, E. mivati, and E. maxima.Feed as the sole ration for 21 consecutive days to chickens that are at risk of developing, but not yet showing clinical signs of, necrotic enteritis associated with Clostridium perfringens. To assure responsible antimicrobial drug use in broiler chickens, treatment administration must begin on or before 18 days of age. Do not allow adult turkeys, horses, or other equines access to narasin formulations. Ingestion of narasin by these species has been fatal. Narasin as provided by No. 058198 in § 510.600(c) of this chapter.058198
(iv)13.6 to 40.9 Narasin, 27 to 45 plus nicarbazin, 27 to 45 Broiler chickens: For the prevention of mortality caused by necrotic enteritis associated with Clostridium perfringens; and for the prevention of coccidiosis caused by Eimeria necatrix, E. tenella, E. acervulina, E. brunetti, E. mivati, and E. maxima Feed as the sole ration for 21 consecutive days to chickens that are at risk of developing, but not yet showing clinical signs of, necrotic enteritis associated with Clostridium perfringens. Avilamycin has not been demonstrated to be effective in broiler chickens showing clinical signs of necrotic enteritis prior to the start of medication. To assure responsible antimicrobial drug use in broiler chickens, treatment administration must begin on or before 18 days of age. The safety of avilamycin has not been established in chickens intended for breeding purposes. Do not allow adult turkeys, horses, or other equines access to narasin formulations. Ingestion of narasin by these species has been fatal. Do not feed to chickens producing eggs for human consumption. Narasin and nicarbazin as provided by No. 058198 in § 510.600(c) of this chapter 058198
(v)13.6 to 40.9Salinomycin sodium, 40 to 60Broiler chickens: For the prevention of mortality caused by necrotic enteritis associated with Clostridium perfringens; and for the prevention of coccidiosis caused by Eimeria tenella, E. necatrix, E. acervulina, E. maxima, E. brunetti, and E. mivati.Feed as the sole ration for 21 consecutive days. Feed to chickens that are at risk of developing, but not yet showing clinical signs of, necrotic enteritis associated with Clostridium perfringens. Not approved for use with pellet binders. To assure responsible antimicrobial drug use in broiler chickens, treatment administration must begin on or before 18 days of age. The safety of avilamycin has not been established in chickens intended for breeding purposes. Avilamycin has not been demonstrated to be effective in broiler chickens showing clinical signs of necrotic enteritis prior to the start of medication. Do not feed to laying hens producing eggs for human consumption. May be fatal if fed to adult turkeys or to horses. Salinomycin as provided by No. 016592 in § 510.600(c) of this chapter.058198
(2)Swine— Avilamycin in grams/ton Combinationin grams/ton Indications for use Limitations Sponsor
(i)73Weaned pigs less than 14 weeks of age: For the reduction in incidence and overall severity of diarrhea in the presence of pathogenic Escherichia coli in groups of weaned pigsFeed as the sole ration for 21 consecutive days. To assure responsible antimicrobial drug use in pigs, do not administer to pigs 14 weeks of age or older058198
(ii)[Reserved] [80 FR 61297, Oct. 13, 2015, as amended at 80 FR 76387, Dec. 9, 2015; 81 FR 17609, Mar. 30, 2016; 81 FR 48703, July 26, 2016; 81 FR 59134, Aug. 29, 2016; 81 FR 67152, Sept. 30, 2016; 82 FR 11509, Feb. 24, 2017; 83 FR 14587, Apr. 5, 2018; 83 FR 64741, Dec. 18, 2018; 84 FR 8974, Mar. 13, 2019; 84 FR 33001, July 11, 2019; 85 FR 4209, Jan. 24, 2020; 85 FR 45308, July 28, 2020; 86 FR 13188, Mar. 8, 2021; 86 FR 14821, Mar. 19, 2021; 88 FR 55567, Aug. 16, 2023; 90 FR 40971, Aug. 22, 2025]
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§ 558.68
Avilamycin.
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