Regulations last checked for updates: Nov 23, 2024

Title 21 - Food and Drugs last revised: Nov 21, 2024
§ 558.55 - Amprolium.

(a) Specifications. Type A medicated article containing 25 percent amprolium.

(b) Sponsor. No. 016592 in § 510.600(c) of this chapter.

(c) Related tolerances. See § 556.50 of this chapter.

(d) Special considerations. Do not use in Type B or Type C medicated feeds containing bentonite.

(e) Conditions of use—(1) Cattle. It is used as follows:

Amprolium in grams per ton Indications for use Limitations Sponsor
(i) 113.5 to 11, 350; to provide 5 milligrams per kilogram of body weight per dayCalves: As an aid in the prevention of coccidiosis caused by Eimeria bovis and E. zuerniiTop-dress on or mix in the daily ration. Feed for 21 days when experience indicates that coccidiosis is likely to be a hazard, as the sole source of amprolium. Withdraw 24 hours before slaughter. A withdrawal period has not been established for this product in preruminating calves. Do not use in calves to be processed for veal016592
(ii) 113.5 to 11, 350; to provide 10 milligrams per kilogram of body weight per dayCalves: As an aid in the treatment of coccidiosis caused by Eimeria bovis and E. zuerniiTop-dress on or mix in the daily ration. Feed for 5 days as the sole source of amprolium. Withdraw 24 hours before slaughter. A withdrawal period has not been established for this product in preruminating calves. Do not use in calves to be processed for veal016592

(2) Chickens. It is used as follows:

Amprolium in grams per ton Combination in grams per ton Indications for use Limitations Sponsor
(i) 36.3 to 113.5Replacement chickens: For development of active immunity to coccidiosisFeed continuously until onset of production as follows:016592
Growing conditions Up to 5 weeks of age From 5 to 8 weeks of age Over 8 weeks of age
Amprolium in grams per ton Amprolium in grams per ton Amprolium in grams per ton
Severe exposure to coccidiosis113.572.6-113.536.3-113.5
(0.0125%)(0.008%-0.0125%)(0.004%-0.0125%)
Moderate exposure to coccidiosis72.6-113.554.5-113.536.3-113.5
(0.008%-0.0125%)(0.006%-0.0125%)(0.004%-0.0125%)
Slight exposure to coccidiosis36.3-113.536.3-113.536.3-113.5
(0.004%-0.0125%)(0.004%-0.0125%)(0.004%-0.0125%)
Amprolium in grams per ton Combination in grams per ton Indications for use Limitations Sponsor
(ii) 36.3 to 113.5Bacitracin methylenedisalicylate 4 to 50Replacement chickens: For development of active immunity to coccidiosis; and for increased rate of weight gain and improved feed efficiencyFeed according to subtable in item (i). Bacitracin methylenedisalicylate as provided by No. 054771 in § 510.600(c) of this chapter054771
(iii) 72.6 to 113.5Broiler chickens: For prevention of coccidiosis caused by Eimeria tenella onlyFeed continuously as the sole ration; as sole source of amprolium016592
(iv) 72.6 to 113.5Bambermycins 1 to 2Broiler chickens: For prevention of coccidiosis caused by Eimeria tenella only; and for increased rate of weight gain and improved feed efficiencyFeed continuously as the sole ration; as sole source of amprolium. Bambermycins as provided by No. 016592 in § 510.600(c) of this chapter016592
(v) 113.51. Laying chickens: For prevention of coccidiosisFeed continuously as the sole ration; as the sole source of amprolium016592
2. Laying chickens: For treatment of coccidiosis in moderate outbreaksFeed for 2 weeks
(vi) 113.5 to 2271. Replacement chickens: For prevention of coccidiosis where immunity to coccidiosis is not desiredFeed continuously from day-old until onset of production; as the sole source of amprolium016592
2. Broiler chickens: For prevention of coccidiosis where immunity to coccidiosis is not desiredFeed continuously as the sole ration; as sole source of amprolium
(vii) 113.5 to 227Bambermycins 1 to 2Broiler chickens: For prevention of coccidiosis where immunity to coccidiosis is not desired; and for increased rate of weight gain and improved feed efficiencyFeed continuously as the sole ration; as sole source of amprolium. Bambermycins as provided by No. 016592 in § 510.600(c) of this chapter016592
(viii) 227Laying chickens: For treatment of coccidiosis in severe outbreaks.Feed for 2 weeks016592

(3) Turkeys. It is used as follows:

Amprolium in grams per ton Combination in grams per ton Indications for use Limitations Sponsor
(i) 113.5Bambermycins 1 to 4Growing turkeys: For prevention of coccidiosis; and for increased rate of weight gain and improved feed efficiencyFeed continuously as the sole source of amprolium; bambermycins as provided by No. 016592 in § 510.600(c) of this chapter016592
(ii) 113.5 to 227Turkeys: For prevention of coccidiosisFeed continuously as the sole ration; as sole source of amprolium016592

(4) Pheasants. It is used as follows:

Amprolium in grams per ton Combination in grams per ton Indications for use Limitations Sponsor
(i) 159Growing pheasants: For the prevention of coccidiosis caused by Eimeria colchici, E. duodenalis, and E. phasianiFeed continuously as sole ration. Use as sole source of amprolium016592
(ii) [Reserved]

(5) Permitted combinations. Amprolium may also be used in combination with:

(i) Virginiamycin as in § 558.635.

(ii) [Reserved]

[41 FR 10985, Mar. 15, 1976] Editorial Note:For Federal Register citations affecting § 558.55, see the List of CFR Sections Affected, which appears in the Finding Aids section of the printed volume and at www.govinfo.gov.
source: 40 FR 13959, Mar. 27, 1975, unless otherwise noted.
cite as: 21 CFR 558.55