Title 21
SECTION 558.258
558.258 Fenbendazole.
§ 558.258 Fenbendazole.(a) Specifications. Type A medicated articles: 4 percent (18.1 grams per pound (g/lb)), 8 percent (36.2 g/lb), and 20 percent (90.7 g/lb) fenbendazole.
(b) Approvals. See No. 000061 in § 510.600(c) of this chapter.
(c) Related tolerances. See § 556.275 of this chapter.
(d) Special considerations. See § 500.25 of this chapter.
(e) Conditions of use - (1) Turkeys.
| Amount fenbendazole in grams per ton | Combination in grams per ton | Indications for use | Limitations | Sponsor |
|---|---|---|---|---|
| 14.5 (16 parts per million) | Growing turkeys: For the removal and control of gastrointestinal worms: roundworms, adult and larvae (Ascaridia dissimilis); cecal worms, adult and larvae (Heterakis gallinarum), an important vector of Histomonas meleagridis (Blackhead) | Feed continuously as the sole ration for 6 days. For growing turkeys only | 000061 |
(2) Swine.
| Fenbendazole in grams per ton |
Combination in grams per ton | Indications for use | Limitations | Sponsors |
|---|---|---|---|---|
| (i) 10 to 300 (to provide 9 milligrams per kilogram (mg/kg) of body weight) given over a 3- to 12-day period | For the removal and control of adult stage lungworms (Metastrongylus apri and M. pudendotectus); adult and larvae (L3, 4 stages - liver, lung, intestinal forms) large roundworms (Ascaris suum); adult stage nodular worms (Oesophagostomum dentatum, O. quadrispinulatum); adult stage small stomach worms (Hyostrongylus rubidus); adult and larvae (L2, 3, 4 stages - intestinal mucosal forms) whipworms (Trichuris suis); adult and larvae kidney worms (Stephanurus dentatus) | Feed as the sole ration | 000061 | |
| (ii) 10 to 300 (to provide 9 mg/kg of body weight) | Bacitracin methylenedisalicylate, 10 to 30 | Growing/finishing swine: For the removal and control of adult stage lungworms (Metastrongylus apri and M. pudendotectus); adult and larvae (L3, 4 stages - liver, lung, intestinal forms) large roundworms (Ascaris suum); adult stage nodular worms (Oesophagostomum dentatum, O. quadrispinulatum); adult stage small stomach worms (Hyostrongylus rubidus); adult and larvae (L2, 3, 4 stages - intestinal mucosal forms) whipworms (Trichuris suis); adult and larvae kidney worms (Stephanurus dentatus); and for increased rate of weight gain and improved feed efficiency | Feed as the sole ration. Under conditions of continued exposure to parasites, retreatment may be needed after 4 to 6 weeks. Bacitracin methylenedisalicylate as provided by No. 054771 in § 510.600(c) of this chapter | 054771 |
| (iii) 10 to 300 (to provide 9 mg/kg of body weight) | Bacitracin methylenedisalicylate, 250 | 1. Growing/finishing swine: For the removal and control of adult stage lungworms (Metastrongylus apri and M. pudendotectus); adult and larvae (L3, 4 stages - liver, lung, intestinal forms) large roundworms (Ascaris suum); adult stage nodular worms (Oesophagostomum dentatum, O. quadrispinulatum); adult stage small stomach worms (Hyostrongylus rubidus); adult and larvae (L2, 3, 4 stages - intestinal mucosal forms) whipworms (Trichuris suis); adult and larvae kidney worms (Stephanurus dentatus); and for control of swine dysentery associated with Treponema hyodysenteriae on premises with a history of swine dysentery, but where signs of disease have not yet occurred; or following an approved treatment of the disease condition | 1. Growing/finishing swine: Feed as sole ration. Not for use in growing and finishing swine that weigh more than 250 lbs. Diagnosis of swine dysentery should be confirmed by a veterinarian when results are not satisfactory. Under conditions of continued exposure to parasites, retreatment may be needed after 4 to 6 weeks. Bacitracin methylenedisalicylate as provided by No. 054771 in § 510.600(c) of this chapter | 054771 |
| 2. Pregnant sows: For the removal and control of adult stage lungworms (Metastrongylus apri and M. pudendotectus); adult and larvae (L3, 4 stages - liver, lung, intestinal forms) large roundworms (Ascaris suum); adult stage nodular worms (Oesophagostomum dentatum, O. quadrispinulatum); adult stage small stomach worms (Hyostrongylus rubidus); adult and larvae (L2, 3, 4 stages - intestinal mucosal forms) whipworms (Trichuris suis); adult and larvae kidney worms (Stephanurus dentatus); for control of clostridial enteritis in suckling pigs caused by Clostridium perfringens | 2. Pregnant sows: Feed as sole ration. Diagnosis of clostridial enteritis should be confirmed by a veterinarian when results are not satisfactory. Under conditions of continued exposure to parasites, retreatment may be needed after 4 to 6 weeks. Bacitracin methylenedisalicylate as provided by No. 054771 in § 510.600(c) of this chapter. |
(3) Cattle.
| Amount fenbendazole | Indications for use | Limitations | Sponsor |
|---|---|---|---|
| (i) 5 mg/kg body weight (2.27 mg/lb) | Dairy and beef cattle: For the removal and control of: Lungworms (Dictyocaulus viviparus); Stomach worms: barberpole worms (Haemonchus contortus), brown stomach worms (Ostertagia ostertagi), small stomach worms (Trichostrongylus axei); Intestinal worms: hookworms (Bunostomum phlebotomum), thread-necked intestinal worms (Nematodirus helvetianus), small intestinal worms (Cooperia oncophora and C. punctata); Bankrupt worms (Trichostrongylus colubriformis); and Nodular worms (Oesophagostomum radiatum). | Feed as the sole ration or as a top dress for one day. Retreatment may be needed after 4 to 6 weeks. Cattle must not be slaughtered within 13 days following last treatment. For dairy cattle the milk discard time is zero hours. A withdrawal period has not been established for this product in pre-ruminating calves. Do not use in calves to be processed for veal. | 000061 |
| (ii) [Reserved] |
(iii) Free-choice feeds - (A) Amount. 5 mg/kg body weight (2.27 mg/lb), including the following formulations:
| Ingredient 1 | Percent | International Feed No. |
|---|---|---|
| (1) Free-choice, dry Type C feed: | ||
| Salt (sodium chloride) | 59.00 | 6-04-152 |
| Monosodium phosphate | 31.16 | 6-04-288 |
| Dried cane molasses | 3.12 | 4-04-695 |
| Zinc sulfate | 0.76 | 6-05-556 |
| Copper sulfate | 0.45 | 6-01-720 |
| Fenbendazole 20% Type A article | 5.51 | n/a |
| (2) Free-choice, dry Type C feed: | ||
| Salt (sodium chloride) | 35.93 | 6-04-152 |
| Dicalcium phosphate (18.5% P) | 32.44 | 6-00-080 |
| Calcium carbonate (38% Ca) | 15.93 | 6-01-069 |
| Magnesium oxide (56% Mg) | 10.14 | 6-02-756 |
| Zinc sulfate | 1.47 | 6-05-556 |
| Mineral oil | 1.00 | 8-03-123 |
| Dried cane molasses (46% sugars) | 0.98 | 4-04-695 |
| Potassium iodide | 0.01 | 6-03-759 |
| Fenbendazole 20% Type A article | 2.10 | n/a |
| (3) Free-choice, liquid Type C feed: | ||
| Cane molasses 2 | 80.902 | 4-13-251 |
| Water | 9.36 | n/a |
| Urea solution, 55% | 7.05 | 5-05-707 |
| Phosphoric acid 75% (feed grade) | 2.00 | 6-03-707 |
| Xantham gum | 0.20 | 8-15-818 |
| Trace minerals | 0.20 | n/a |
| Vitamin premix | 0.01 | n/a |
| Fenbendazole 20% Type A article | 0.278 | n/a |
1The content of any added vitamin and trace mineral may be varied; however, they should be comparable to those used by the manufacturer for other free-choice cattle feeds. Formulation modifications require FDA approval prior to marketing. Selenium is not approved for the free-choice formulations described in paragraph (e)(3)(iii) of this section. Free-choice cattle feeds containing selenium must comply with published regulations (see 21 CFR 573.920).
2The percentage of cane molasses and water in the formulation may be adjusted as needed in order to bring the brix value of the molasses to the industry standard of 79.5 brix.
(B) Indications for use. As in paragraph (e)(3)(i) of this section.
(C) Limitations. Feed a total of 5 mg of fenbendazole per kg (2.27 mg/lb) of body weight to cattle over a 3- to 6-day period. Retreatment may be needed after 4 to 6 weeks. Cattle must not be slaughtered within 13 days following last treatment. For dairy cattle the milk discard time is zero hours. A withdrawal period has not been established for this product in pre-ruminating calves. Do not use in calves to be processed for veal.
(4) Horses.
| Amount fenbendazole in grams per ton | Indications for use | Limitations | Sponsor |
|---|---|---|---|
| (i) 4,540 | 5 mg/kg body weight (2.27 mg/lb) for the control of large strongyles (Strongylus edentatus, S. equinus, S. vulgaris, Triodontophorus spp.), small strongyles (Cyathostomum spp., Cylicocyclus spp., Cylicostephanus spp.), and pinworms (Oxyuris equi); 10 mg/kg body weight (4.54 mg/lb) for the control of ascarids (Parascaris equorum). | Feed at the rate of 0. 1lb of feed per 100 lb of body weight to provide 2.27 mg fenbendazole/lb of body weight in a 1-day treatment or 0.2 lb of feed per 100 lb of body weight to provide 4.54 mg fenbendazole/lb of body weight in a 1-day treatment. All horses must be eating normally to ensure that each animal consumes an adequate amount of the medicated feed. Regular deworming at intervals of 6 to 8 weeks may be required due to the possibility of reinfection. Do not use in horses intended for human consumption. | 000061 |
| (ii) [Reserved] |
(5) Zoo and wildlife animals.
| Species/Class | Amount fenbendazole | Indications for use | Limitations | Sponsor |
|---|---|---|---|---|
| (i) Feral swine (Sus scrofa) | 3 mg/kg/day for 3 days. | For the removal and control of kidney worm (Stephanurus dentatus), roundworm (Ascaris suum), nodular worm (Oesophagostomum dentatum) | Use as complete feed. Prior withdrawal of feed or water is not necessary. Retreatment may be required in 6 weeks. Do not use 14 days before or during the hunting season | 000061 |
| (ii) Ruminants (subfamily Antilopinae, Hippotraginae, Caprinae) | 2.5 mg/kg/day for 3 days. | For the removal and control of small stomach worm (Trichostrongylus spp.), thread necked intestinal worm (Nematodirus spp.), barberpole worm (Haemonchus spp.), whipworm (Trichuris spp.) | Use as complete feed. Prior withdrawal of feed or water is not necessary. Retreatment may be required in 6 weeks. Do not use 14 days before or during the hunting season | 000061 |
| (iii) Rocky mountain bighorn sheep (Ovis c. canadensis) | 10 mg/kg/day for 3 days. | For the removal and control of Protostrongylus spp | Use as complete feed. Prior withdrawal of feed or water is not necessary. Retreatment may be required in 6 weeks. Do not use 14 days before or during the hunting season | 000061 |
(6) Fenbendazole may also be used in combination with:
(i) [Reserved]
(ii) Lincomycin as in § 558.325.
[66 FR 58935, Nov. 26, 2001, as amended at 68 FR 34534, June 10, 2003; 72 FR 66046, Nov. 27, 2007; 73 FR 58873, Oct. 8, 2008; 74 FR 61517, Nov. 25, 2009; 79 FR 13545, Mar. 11, 2014; 81 FR 17609, Mar. 30, 2016; 81 FR 95005, Dec. 27, 2016; 84 FR 12499, Apr. 2, 2019]