Section 520.445 - Chlortetracycline and sulfamethazine powder(a)Specifications. Each pound of soluble powder contains chlortetracycline bisulfate equivalent to 102.4 grams (g) of chlortetracycline hydrochloride and sulfamethazine bisulfate equivalent to 102.4 g of sulfamethazine.(b)Sponsor. See No. 016592 in § 510.600(c) of this chapter.(c)Related tolerances. See §§ 556.150 and 556.670 of this chapter.(d)Conditions of use in swine. Administer in drinking water as follows: (1)Amount. 250 milligrams (mg) of chlortetracycline and 250 mg of sulfamethazine per gallon.(2)Indications for use. For the prevention and treatment of bacterial enteritis; as an aid in the reduction of the incidence of cervical abscesses; and as an aid in the maintenance of weight gains in the presence of bacterial enteritis and atrophic rhinitis.(3)Limitations. Use as the sole source of chlortetracycline and sulfonamide. Not to be used for more than 28 consecutive days. Withdraw 15 days before slaughter. Federal law restricts this drug to use by or on the order of a licensed veterinarian. 76 FR 49649 , Aug. 11, 2011, as amended at 81 FR 17607 , Mar. 30, 2016; 81 FR 94989 , Dec. 27, 2016 As amended at 81 FR 17607, 3/30/2016; 81 FR 94989, 12/27/2016