[Code of Federal Regulations] [Title 21, Volume 6] [Revised as of January 1, 2003] From the U.S. Government Printing Office via GPO Access [CITE: 21CFR558.185] [Page 397-398] TITLE 21--FOOD AND DRUGS CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) PART 558--NEW ANIMAL DRUGS FOR USE IN ANIMAL FEEDS--Table of Contents Subpart B--Specific New Animal Drugs for Use in Animal Feeds Sec. 558.185 Coumaphos. (a) Approvals. Type A medicated articles: (1) [Reserved] (2) 1.12 and 11.2 percent to 017800 in Sec. 510.600(c) of this chapter for use as in paragraph (d)(1)(ii) of this section. (b) Special considerations. Adequate directions and warnings for use must be given and shall include a statement that coumaphos is a cholinesterase inhibitor and that animals being treated with coumaphos should not be exposed during or within a few days before or after treatment to any other cholinesterase-inhibiting drugs, insecticides, pesticides, or chemicals. (c) Related tolerances. See 40 CFR 180.189. (d) Conditions of use. It is used as follows: (1) Beef and dairy cattle--(i) Amount. Coumaphos 0.00012 lb. (0.054 gram) per 100 lb. body weight per day. (a) Indications for use. As an aid in the reduction of fecal breeding flies through control of fly larvae. (b) Limitations. Feed for the duration of fly season in a Type C feed containing 0.0033 percent or in a feed Type B feed containing not over 0.0066 percent coumaphos; do not feed to animals less than 3 months old; not for use in pelleted feeds. (ii) Amount. Coumaphos, 0.0002 lb. (0.091 gram) per 100 lb. body weight per day. [[Page 398]] (a) Indications for use. Control of gastrointestinal roundworms (Haemonchus spp., Ostertagia spp., Cooperia spp., Nematodirus spp., Trichostrongylus spp.). (b) Limitations. Feed 0.0002 lb. (0.091 gram) per 100 lb. body weight per day for 6 consecutive days in the normal grain ration to which the animals are accustomed but not in rations containing more than 0.1 percent coumaphos; do not feed to animals less than 3 months old; do not feed to sick animals or animals under stress, such as those just shipped, dehorned, castrated, or weaned within the last 3 weeks; do not feed in conjunction with oral drenches or with feeds containing phenothiazine. Should conditions warrant, repeat treatment at 30-day intervals. (2) Laying chickens--(i) Amount. Coumaphos 27.2 grams per ton (0.003 percent). (ii) Indications for use. For control of capillary worm (Capillaria obsignata) and as an aid in control of common round worm (Ascaridia galli) and cecal worm (Heterakis gallinae). (iii) Limitations. In Type C feed; administer continuously as the total feed ration for 14 days; when reinfection occurs, treatment may be repeated but not sooner than 3 weeks after the end of the previous treatment; do not feed to chickens within 10 days of vaccination or other conditions of stress; treatment of colored breeds of commercial layers should be avoided while in production since these breeds appear to be more sensitive to coumaphos than white breeds; as sole medication; medications in general should be avoided while birds are approaching peak production; such interruption of normal feeding practices may upset the flock and lower egg production; diagnosis by competent personnel is essential; flock condition and production records should be carefully evaluated prior to treatment. (3) Replacement pullets--(i) Amount. Coumaphos 36.3 grams per ton (0.004 percent). (ii) Indications for use. For control of capillary worm (Capillaria obsignata) and as an aid in control of common roundworm (Ascaridia galli) and cecal worm (Heterakis gallinae). (iii) Limitations. In Type C feed; administer before the onset of production; diagnosis by competent personnel is essential; administer continuously as total feed ration for from 10 to 14 days; do not feed to chickens under 8 weeks of age nor within 10 days of vaccination or other conditions of stress; if birds are maintained on contaminated litter or exposed to infected birds, a second 10 to 14 day treatment is recommended but not sooner than 3 weeks after the end of the previous treatment; as sole medication; if reinfection occurs after production begins, repeat treatment as recommended for laying flocks. [40 FR 13959, Mar. 27, 1975, as amended at 42 FR 1463, Jan. 7, 1977; 51 FR 7397, Mar. 3, 1986; 52 FR 2684, Jan. 26, 1987; 61 FR 34729, July 3, 1996]