558.635—Virginiamycin.
(a) Approvals.
Type A medicated articles. (1) 1.1 percent activity (5 grams per pound), 2.2 percent activity (10 grams per pound), 4.4 percent activity (20 grams per pound), 11 percent activity (50 grams per pound), and 50 percent activity (227 grams per pound) used as in paragraph (d) of this section; and 30 percent activity (136.2 grams per pound) for the manufacture of Type C medicated feed for cattle used as in paragraph (d)(3); to 066104 in § 510.600(c) of this chapter.
(2)
2.2 percent activity (10 grams per pound) to 046573, 016968, and 017790 in § 510.600(c) of this chapter for use as in paragraphs (d)(1)(iv) and (d)(1)(v) of this section.
(2)
Dilute Type A article with at least 10 pounds of a feed ingredient prior to final mixing in 1 ton of Type C feed.
(i)
100 grams per ton for 2 weeks, for treatment of swine dysentery in nonbreeding swine over 120 pounds.
(ii)
100 grams per ton for 2 weeks, 50 grams per ton thereafter, for treatment and control of swine dysentery in swine up to 120 pounds.
(iii)
25 grams per ton, as an aid in control of dysentery in swine up to 120 pounds. For use in animals or on premises with a history of swine dysentery but where symptoms have not yet occurred.
(iv)
10 grams per ton from weaning up to 120 pounds for increased rate of weight gain and improved feed efficiency, followed by 5 grams per ton to market weight for increased rate of weight gain and improved feed efficiency. For continuous use from weaning to market weight.
(v)
10 grams per ton from weaning up to 120 pounds for increased rate of weight gain and improved feed efficiency, followed by 5 to 10 grams per ton to market weight for increased rate of weight gain. For continuous use from weaning to market weight.
(i)
5 to 15 grams per ton for increased rate of weight gain, for use in broiler chickens, not for use in layers.
(ii)
5 grams per ton for increased rate of weight gain and improved feed efficiency in broiler chickens, not for use in layers.
(iii)
20 grams per ton for prevention of necrotic enteritis caused by Clostridium perfringens susceptible to virginiamycin in broiler chickens; not for use in layers.
(iv)
10 to 20 grams per ton for increased rate of weight gain and improved feed efficiency in growing turkeys.
(i)
16.0 to 22.5 grams per ton to provide 100 to 340 milligrams per head per day for increased rate of weight gain.
(ii)
13.5 to 16.0 grams per ton to provide 85 to 240 milligrams per head per day for reduction of incidence of liver abscesses.
(iii)
11.0 to 16.0 grams per ton to provide 70 to 240 milligrams per head per day for improved feed efficiency.
(iv)
Feed continuously as sole ration to cattle fed in confinement for slaughter. Not for use in animals intended for breeding.