Section 520.2260a - Sulfamethazine oblets and boluses(a)Specifications. Each oblet or bolus contains: (1) 2.5, 5, or 15 grams sulfamethazine.(2) 5 grams sulfamethazine.(b)Sponsors. See sponsors in § 510.600(c) of this chapter for use of products described in paragraph (a) of this section. (1) No. 016592 for use of products described in paragraph (a)(1) of this section.(2) No. 054771 for use of product described in paragraph (a)(2) of this section.(c)Related tolerances. See § 556.670 of this chapter.(d)Conditions of use.(1) Oblets and boluses described in paragraph (a)(1) of this section: (i)Amount. Administer as a single dose 100 milligrams per pound (mg/lb) of body weight the first day and 50 mg/lb of body weight on each following day.(ii)Indications for use - (A)Beef cattle and nonlactating dairy cattle. For the treatment of bacterial pneumonia and bovine respiratory disease complex (shipping fever complex) (Pasteurella spp.), colibacillosis (bacterial scours) (Escherichia coli), necrotic pododermatitis (foot rot) (Fusobacterium necrophorum), calf diphtheria (Fusobacterium necrophorum), acute mastitis (Streptococcus spp.), acute metritis (Streptococcus spp.), and coccidiosis (Eimeria bovis and E. zurnii).(B)Horses. For the treatment of bacterial pneumonia (secondary infections associated with Pasteurella spp.), strangles (Streptococcus equi), and bacterial enteritis (Escherichia coli).(iii)Limitations. Do not administer for more than 5 consecutive days. Do not treat cattle within 10 days of slaughter. Do not use in female dairy cattle 20 months of age or older. Use of sulfamethazine in this class of cattle may cause milk residues. A withdrawal period has not been established for this product in preruminating calves. Do not use in calves to be processed for veal. Do not use in horses intended for human consumption. Federal law restricts this drug to use by or on the order of a licensed veterinarian.(2) Boluses described in paragraph (a)(2) of this section: (i)Amount. Administer 10 grams (2 boluses) of sulfamethazine per 100 pounds of body weight the first day, then 5 grams (1 bolus) of sulfamethazine per 100 pounds of body weight daily for up to 4 additional consecutive days.(ii)Indications for use - (A)Ruminating beef and dairy calves. For treatment of the following diseases caused by organisms susceptible to sulfamethazine: bacterial scours (colibacillosis) caused by Escherichia coli; necrotic pododermatitis (foot rot) and calf diphtheria caused by Fusobacterium necrophorum; bacterial pneumonia associated with Pasteurella spp.; and coccidiosis caused by Eimeria bovis and E. zurnii.(iii)Limitations. Do not administer for more than 5 consecutive days. Do not treat calves within 11 days of slaughter. Do not use in calves to be slaughtered under 1 month of age or in calves being fed an all milk diet. Do not use in female dairy cattle 20 months of age or older; such use may cause drug residues in milk. Federal law restricts this drug to use by or on the order of a licensed veterinarian. 87 FR 58961 , Sept. 29, 2022, as amended at 88 FR 14897 , Mar. 10, 2023; 88 FR 16547 , Mar. 20, 2023 81 FR 17607, 3/30/2016; 87 FR 58961, 9/29/2022; as amended at 88 FR 14897, 3/10/2023; 88 FR 16547, 3/20/2023