§ 520.100a - Amprolium drinking water.

(a) Chemical name. 1-(4-Amino-2-n-propyl-5-pyrimidinylmethyl)-2-picolinium chloride hydrochloride.

(b) Sponsors. See Nos. 050604 and 051311 in § 510.600(c) of this chapter.

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

(d) Conditions of use. It is used in drinking water as follows:

(1) Chickens and turkeys—(i) Amount. 20 percent soluble powder.

(ii) Indications for use. Treatment of coccidiosis.

(iii) Limitations. Administer at the 0.012 percent level in drinking water as soon as coccidiosis is diagnosed and continue for from 3 to 5 days (in severe outbreaks, give amprolium at the 0.024 percent level); continue with 0.006 percent amprolium-medicated water for an additional 1 to 2 weeks; no other source of drinking water should be available to the birds during this time; as sole source of amprolium.

(2) Calves—(i) Amount. 9.6 percent solution or 20 percent soluble powder.

(a) Indications for use. As an aid in the treatment of coccidiosis caused by Eimeria bovis and E. zurnii.

(b) Limitations. Add 16 fluid ounces of the 9.6 percent solution to each 100 gallons of drinking water; or 4 ounces of the soluble powder to each 50 gallons of drinking water; at the usual rate of water consumption, this will provide an intake of approximately 10 milligrams per kilogram (2.2 pounds) of body weight; offer this solution as the only source of water for 5 days; for a satisfactory diagnosis, a microscopic examination of the feces should be done by a veterinarian or diagnostic laboratory before treatment; when treating outbreaks, the drug should be administered promptly after diagnosis is determined; 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 veal.

(ii) Amount. 9.6 percent solution or 20 percent soluble powder.

(a) Indications for use. As an aid in the prevention of coccidiosis caused by Eimeria bovis and E. zurnii.

(b) Limitations. Add 8 fluid ounces of the 9.6 percent solution or 4 ounces of the 20 percent soluble powder to each 100 gallons of drinking water; at the usual rate of water consumption, this will provide an intake of approximately 5 milligrams per kilogram (2.2 pounds) of body weight; offer this solution as the only source of water for 21 days during periods of exposure or when experience indicates that coccidiosis is likely to be a hazard; 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 veal.