Regulations last checked for updates: Nov 26, 2024

Title 21 - Food and Drugs last revised: Nov 21, 2024
§ 558.305 - Laidlomycin.

(a) Specifications. Type A medicated articles containing 50 grams laidlomycin propionate potassium per pound.

(b) Sponsor. See No. 054771 in § 510.600(c) of this chapter.

(c) Tolerances. See § 556.346 of this chapter.

(d) Special considerations. (1) Laidlomycin liquid Type B feeds may be manufactured from dry laidlomycin Type A articles. The liquid Type B feeds must have a pH of 6.0 to 8.0, dry matter of 62 to 75 percent, and bear appropriate mixing directions as follows:

(i) For liquid feeds stored in recirculating tank systems: Recirculate immediately prior to use for no less than 10 minutes, moving not less than 1 percent of the tank contents per minute from the bottom of the tank to the top. Recirculate daily as described even when not used.

(ii) For liquid feeds stored in mechanical, air, or other agitation type tank systems: Agitate immediately prior to use for not less than 10 minutes, creating a turbulence at the bottom of the tank that is visible at the top. Agitate daily as described even when not used.

(2) The expiration date for the liquid Type B feed is 21 days after date of manufacture. The expiration date for the dry Type C feed made from the liquid Type B feed is 7 days after date of manufacture.

(3) Labeling for all Type B feeds (liquid and dry) and Type C feeds containing laidlomycin shall bear the following statements:

(i) Do not allow horses or other equines access to feeds containing laidlomycin propionate potassium.

(ii) The safety of laidlomycin propionate potassium in unapproved species has not been established.

(iii) Not for use in animals intended for breeding.

(e) Conditions of use. It is used in cattle being fed in confinement for slaughter as follows:

Laidlomycin in grams per ton Combination in grams per ton Indications for use Limitations Sponsor
(1) 5 For improved feed efficiency and increased rate of weight gain.Feed continuously in a Type C feed at a rate of 30 to 75 mg/head/day.054771
(2) 5 to 10 For improved feed efficiency.Feed continuously in a Type C feed at a rate of 30 to 150 milligrams/head/day.054771

(f) Laidlomycin may also be used in combination with chlortetracycline as in § 558.128.

[59 FR 18297, Apr. 18, 1994, as amended at 60 FR 53509, Oct. 16, 1995; 62 FR 9929, Mar. 5, 1997; 63 FR 27845, May 21, 1998; 66 FR 46706, Sept. 7, 2001; 68 FR 13839, Mar. 21, 2003; 68 FR 42590, July 18, 2003; 69 FR 30198, May 27, 2004; 79 FR 13545, Mar. 11, 2014; 81 FR 95005, Dec. 27, 2016; 86 FR 14823, Mar. 19, 2021]
source: 40 FR 13959, Mar. 27, 1975, unless otherwise noted.
cite as: 21 CFR 558.305