# 558.185 Coumaphos.
(a) *Specifications.* Type A medicated articles containing 1.12, 2.0, 11.2, or 50 percent coumaphos.
(b) *Sponsor.* See No. 058198 in § 510.600(c) of this chapter.
(c) *Related tolerances.* See § 556.168 of this chapter.
(d) *Special considerations.* (1) Labeling shall bear the following warning: The active ingredient coumaphos is a cholinesterase inhibitor. Do not use this product on animals simultaneously or within a few days before or after treatment with, or exposure to, cholinesterase-inhibiting drugs, pesticides, or chemicals.
(2) See § 500.25 of this chapter.
(e) *Conditions of use in laying chickens.*
| Coumaphos ingrams per ton | Indications for use | Limitations | Sponsor |
| --- | --- | --- | --- |
| (1) 27.2 (0.003 percent) | Laying chickens: For control of capillary worm () and as an aid in control of common round worm () and cecal worm () | Feed continuously as the sole ration for 14 days. If 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. | 058198 |
| (2) 36.3 (0.004 percent) | Replacement pullets: For control of capillary worm () and as an aid in control of common round worm () and cecal worm () | Feed continuously as the sole ration for from 10 to 14 days. Do not feed to chickens under 8 weeks of age or 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. If reinfection occurs after production begins, repeat treatment as recommended for laying flocks. | 058198 |
[86 FR 14822, Mar. 19, 2021]