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e-CFR data is current as of February 25, 2021

Title 21Chapter ISubchapter EPart 524 → §524.900

Title 21: Food and Drugs

§524.900   Famphur.

(a) Specifications. The drug is in liquid form containing 13.2 percent famphur.

(b) Sponsor. See No. 000061 in §510.600(c) of this chapter.

(c) Special considerations. Do not use on animals simultaneously or within a few days before or after treatment with or exposure to cholinesterase-inhibiting drugs, pesticides, or chemicals.

(d) Related tolerances. See §556.273 of this chapter.

(e) Conditions of use—(1) Amount. Apply 1 ounce per 200 pounds body weight, not to exceed a total dosage of 4 ounces, from the shoulder to the tail head as a single treatment. Apply as soon as possible after heel fly activity ceases.

(2) Indications for use in beef and nonlactating dairy cattle. For control of cattle grubs and to reduce cattle lice infestations.

(3) Limitations. Do not slaughter within 35 days after treatment. Do not use on lactating dairy cows or dry dairy cows within 21 days of freshening, calves less than 3 months old, animals stressed from castration, overexcitement or dehorning, sick or convalescent animals. Animals may become dehydrated and under stress following shipment. Do not treat until they are in good condition. Brahman and Brahman crossbreeds are less tolerant of cholinesterase-inhibiting insecticides than other breeds. Do not treat Brahman bulls. Swine should be eliminated from area where runoff occurs.

[40 FR 13873, Mar. 27, 1975, as amended at 49 FR 34352, Aug. 30, 1984; 57 FR 7652, Mar. 4, 1992; 59 FR 28769, June 3, 1994; 62 FR 55161, Oct. 23, 1997; 62 FR 61626, Nov. 19, 1997; 69 FR 41427, July 9, 2004; 79 FR 10968, Feb. 27, 2014; 83 FR 48946, Sept. 28, 2018]

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