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Code of Federal Regulations Title 21. Food and Drugs § 21.558.4 Requirement of a medicated feed mill license
Current as of January 02, 2025 | Updated by Findlaw Staff
(a) A feed manufacturing facility must possess a medicated feed mill license in order to manufacture a Type B or Type C medicated feed from a Category II, Type A medicated article.
(b) The manufacture of the following types of feed are exempt from the required license, unless otherwise specified:
(1) Type B or Type C medicated feed using Category I, Type A medicated articles or Category I, Type B or Type C medicated feeds; and
(2) Type B or Type C medicated feed using Category II, Type B or Type C medicated feeds.
(c) The use of Type B and Type C medicated feeds shall also conform to the conditions of use provided for in subpart B of this part.
(d) This paragraph identifies each drug by category, the maximum level of drug in Type B medicated feeds, and the assay limits for the drug in Type A medicated articles and Type B and Type C medicated feeds, as follows:
|
CATEGORY I |
|||
|---|---|---|---|
|
Drug |
Assay |
Type B |
Assay limits |
|
limits |
maximum |
percent 1 |
|
|
percent |
(200x) |
Type B/C 2 |
|
|
Type A |
|||
|
Amprolium with Ethopabate |
94–114 |
22.75 g/lb (5.0%) |
80–120. |
|
Avilamycin |
90-110 |
7.3 g/lb (1.6%) |
80-110 |
|
Bacitracin methylenedisalicylate |
85–115 |
25.0 g/lb (5.5%) |
70–130. |
|
Bacitracin zinc |
84–115 |
5.0 g/lb (1.1%) |
70–130. |
|
Bambermycins |
90–110 |
800 g/ton (0.09%) |
80–120/70–130. |
|
Chlortetracycline |
85–115 |
40.0 g/lb (8.8%) |
80–115/70–130. |
|
Coumaphos |
95–115 |
6.0 g/lb (1.3%) |
80–120. |
|
Decoquinate |
90–105 |
2.72 g/lb (0.6%) |
80–120. |
|
Dichlorvos |
100–115 |
33.0 g/lb (7.3%) |
90–120/80–130. |
|
Diclazuril |
90–110 |
182 g/t (0.02%) |
85–115/70–120 |
|
Efrotomycin |
94–113 |
1.45 g/lb (0.32%) |
80–120 |
|
Iodinated casein |
85–115 |
20.0 g/lb (4.4%) |
75–125. |
|
Laidlomycin propionate potassium |
90–110 |
1 g/pound (0.22%) |
90–115/85–115. |
|
Lasalocid |
95–115 |
40.0 g/lb (8.8%) |
Type B (cattle and sheep): 80–120; Type C (all): 75–125. |
|
Lincomycin |
90–115 |
20.0 g/lb (4.4%) |
80–130. |
|
Lubabegron |
87-107 |
908 g/ton |
85-115/80-120 |
|
Melengestrol acetate |
90–110 |
10.0 g/ton (0.0011%) |
70–120. |
|
Monensin |
85–115 |
40.0 g/lb (8.8%) |
Chickens, turkeys, and |
|
quail: 75–125; Cattle: |
|||
|
5–10 g/ton 80–120;Cattle: 10–30 g/ton 85–115; Goats: 20 g/ton 85–115; Liq. feed: 80–120. |
|||
|
Narasin |
90-110 |
9.0 g/lb (1.98%) |
85-115/75-125. |
|
Nicarbazin (granular) |
90-110 |
9.0 g/lb (1.98%) |
85-115/75-125. |
|
Narasin |
90-110 |
9.0 g/lb (1.98%) |
85-115/75-125. |
|
Nystatin |
85–125 |
5.0 g/lb (1.1%) |
75–125. |
|
Oxytetracycline |
90–120 |
20.0 g/lb (4.4%) |
75–125/65–135. |
|
Poloxalene |
90–110 |
54.48 g/lb (12.0%) |
Liq. feed: 85–115. |
|
Ractopamine |
85-105 |
2.46 g/lb (0.54%) |
80–110/75–125. |
|
Salinomycin |
90–110 |
6.0 g/lb (1.3%) |
80–120. |
|
Semduramicin (as semduramicin sodium) |
90-110 |
2.27 g/lb (0.50%) |
80-110 |
|
Semduramicin (as semduramicin sodium biomass) |
90-110 |
2.27 g/lb (0.50%) |
80-120 |
|
Tylosin |
80–120 |
10.0 g/lb (2.2%) |
75–125. |
|
Tylvalosin |
90-110 |
3.86 g/lb |
85-115 |
|
Virginiamycin |
85–115 |
10.0 g/lb (2.2%) |
70–130. |
|
Zoalene |
92–104 |
11.35 g/lb (2.5%) |
85–115. |
1 Percent of labeled amount.
2 Values given represent ranges for either Type B or Type C medicated feeds. For those drugs that have two range limits, the first set is for a Type B medicated feed and the second set is for a Type C medicated feed. These values (ranges) have been assigned in order to provide for the possibility of dilution of a Type B medicated feed with lower assay limits to make Type C medicated feed.
|
CATEGORY II |
|||
|---|---|---|---|
|
Drug |
Assay limits percent1 Type A |
Type B maximum (100x) |
|
|
Amprolium |
94-114 |
11.35 g/lb (2.5%) |
80-120. |
|
Apramycin |
88-112 |
7.5 g/lb (1.65%) |
80-120. |
|
Carbadox |
90-110 |
2.5 g/lb (0.55%) |
75-125. |
|
Clopidol |
94-106 |
11.4 g/lb (2.5%) |
90-115/80-120. |
|
Erythromycin |
85-115 |
4.625 g/lb (1.02%) |
75-125 |
|
Famphur |
100-110 |
5.5 g/lb (1.21%) |
90-115/80-120. |
|
Fenbendazole |
93-113 |
8.87 g/lb (1.96%) |
75-125. |
|
Florfenicol |
90-110 |
9.1 g/lb (2.0%) |
Swine feed: 85-115 |
|
Catfish feed: 80-110 |
|||
|
Salmonid feed: 80-110 |
|||
|
Halofuginone hydrobromide |
90-115 |
272.0 g/ton (.03%) |
75-125. |
|
Hygromycin B |
90-110 |
1,200 g/ton (0.13%) |
75-125. |
|
Ivermectin |
95–105 |
1,180 g/ton (0.13%) |
80–110. |
|
Maduramicin ammonium |
90-110 |
545 g/ton (.06%) |
80-120. |
|
Morantel tartrate |
90-110 |
66.0 g/lb (14.52%) |
85-115. |
|
Neomycin |
80-120 |
20 g/lb (4.4%) |
70-125 |
|
Oxytetracycline |
80-120 |
20 g/lb (4.4%) |
65-135 |
|
Neomycin sulfate |
80-120 |
100 g/lb (22.0%) |
70-125 |
|
Nicarbazin (granular) |
90-110 |
5.675 g/lb (1.25%) |
85-115/75-125 |
|
Nicarbazin (powder) |
96-104 |
9.08 g/lb (2.00%) |
85-115/75-125 |
|
Novobiocin |
85-115 |
17.5 g/lb (3.85%) |
80-120 |
|
Pyrantel tartrate |
90-110 |
36 g/lb (7.9%) |
75-125 |
|
Robenidine |
95-115 |
1.5 g/lb (0.33%) |
80-120. |
|
Sulfadimethoxine |
90-110 |
Poultry: 5.675 g/lb |
80-115/75-125 |
|
Fish: 85.1 g/lb |
|||
|
Ormetoprim |
90-110 |
Poultry: 3.405 g/lb |
80-115 |
|
Fish: 17.0 g/lb |
|||
|
Sulfamerazine |
85-115 |
18.6 g/lb (4.0%) |
85-115. |
|
Sulfamethazine |
85-115 |
10.0 g/lb (2.2%) |
80-120. |
|
Chlortetracycline |
85-115 |
10.0 g/lb (2.2%) |
85-125/70-130. |
|
Sulfamethazine |
85-115 |
10.0 g/lb (2.2%) |
80-120. |
|
Tylosin |
80-120 |
10.0 g/lb (2.2%) |
75-125. |
|
Sulfaquinoxaline |
98-106 |
11.2 g/lb (2.5%) |
85-115. |
|
Thiabendazole |
94-106 |
45.4 g/lb (10.0%) |
<7% 85-115; >7% 90-110. |
|
Tiamulin hydrogen fumarate |
90-115 |
10 g/lb |
90-115/70-130 |
|
Tilmicosin |
90-110 |
37.9 g/lb (8.35%) |
Swine Type B/C feed: 85-115 |
|
Cattle Type B feed: 85-115 |
|||
|
Cattle Type C feed: 80-110 |
|||
|
Zilpaterol |
90-110 |
680 g/t (0.075%) |
80-110/75-115 |
1 Percent of labeled amount.
2 Values given represent ranges for either Type B or Type C medicated feeds. For those drugs that have two range limit, the first set is for a Type B medicated feed and the second set is for a Type C medicated feed. These values (ranges) have been assigned in order to provide for the possibility of dilution of a Type B medicated feed with lower assay limits to make a Type C medicated feed.
(e) When drugs from both categories are in combination, the Category II requirements will apply to the combination drug product.
Cite this article: FindLaw.com - Code of Federal Regulations Title 21. Food and Drugs § 21.558.4 Requirement of a medicated feed mill license - last updated January 02, 2025 | https://codes.findlaw.com/cfr/title-21-food-and-drugs/cfr-sect-21-558-4/
FindLaw Codes may not reflect the most recent version of the law in your jurisdiction. Please verify the status of the code you are researching with the state legislature before relying on it for your legal needs.
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