[Code of Federal Regulations]
[Title 21, Volume 6]
[Revised as of January 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 21CFR558.342]

[Page 424-427]
 
                        TITLE 21--FOOD AND DRUGS
 
CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN 
                          SERVICES (CONTINUED)
 
PART 558--NEW ANIMAL DRUGS FOR USE IN ANIMAL FEEDS--Table of Contents
 
      Subpart B--Specific New Animal Drugs for Use in Animal Feeds
 
Sec.  558.342  Melengestrol.

    (a) Specifications. (1) Dry Type A medicated articles containing 100 
or 200 milligrams (mg) melengestrol acetate per pound.
    (2) Liquid Type A medicated article containing 500 mg melengestrol 
acetate per pound.
    (b) Approvals. See No. 000009 in Sec.  510.600(c) of this chapter.
    (c) Related tolerances. See Sec.  556.380 of this chapter.
    (d) Special considerations. (1) Type B or C medicated feeds may be 
manufactured from melengestrol acetate liquid Type A articles or Type B 
or C medicated feeds which have a pH of 4.0 to 8.0 and bear appropriate 
mixing directions as follows:
    (i) For liquid Type B or C 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 Type B or C 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) A positionally stable melengestrol acetate liquid Type B or C 
feed will not be subject to the requirements for mixing directions 
prescribed in paragraphs (c)(1) of this section provided it has a pH of 
4.0 to 8.0 and contains a suspending agent(s) sufficient to maintain a 
viscosity of not less than 300 centipoises per second for 3 months.
    (3) Combination Type B or C medicated feeds containing lasalocid 
must be labeled in accordance with Sec.  558.311(d)(5) of this chapter.
    (4) Liquid combination Type B or C medicated feeds containing 
melengestrol acetate and lasalocid must be manufactured in accordance 
with Sec.  558.311(d) of this chapter.
    (5) Combination Type B or C medicated feeds containing monensin must 
be labeled in accordance with Sec.  558.355(d) of this chapter.
    (6) Liquid combination Type B or C medicated feeds containing 
melengestrol acetate and monensin must be manufactured in accordance 
with Sec.  558.355(f)(3)(i) of this chapter.
    (7) Liquid combination Type B or C medicated feeds containing 
melengestrol acetate and tylosin must be manufactured in accordance with 
Sec.  558.625(c) of this chapter.

[[Page 425]]

    (8) Liquid melengestrol acetate may not be mixed with 
oxytetracycline in a common liquid feed supplement.
    (e) Conditions of use--(1) Cattle.

------------------------------------------------------------------------
 Melengestrol   Combination
acetate in mg/  in mg/head/   Indications for     Limitations    Sponsor
   head/day         day             use
------------------------------------------------------------------------
(i) 0.25 to    ............  Heifers fed in    Administer 0.5    000009
 0.5                          confinement for   to 2.0 pounds
                              slaughter: For    (lb)/head/day
                              increased rate    of medicated
                              of weight gain,   feed containing
                              improved feed     0.125 to 1.0 mg
                              efficiency, and   melengestrol
                              suppression of    acetate/lb to
                              estrus (heat).    provide 0.25 to
                                                0.5 mg
                                                melengestrol
                                                acetate/head/
                                                day.
(ii) 0.5       ............  Heifers intended  Administer 0.5    000009
                              for breeding:     to 2.0 lb/head/
                              For suppression   day of Type C
                              of estrus         feed containing
                              (heat).           0.25 to 1.0 mg
                                                melengestrol
                                                acetate/lb to
                                                provide 0.5 mg
                                                melengestrol
                                                acetate/head/
                                                day. Do not
                                                exceed 24 days
                                                of feeding.
(iii) 0.25 to  Lasalocid     Heifers fed in    Add at the rate   000009
 0.5            100 to 360    confinement for   of 0.5 to 2.0
                              slaughter: As     lb/head/day a
                              in paragraph      medicated feed
                              (e)(1)(i) of      (liquid or dry)
                              this section.     containing
                                                0.125 to 1.0 mg
                                                melengestrol
                                                acetate/lb to a
                                                feed containing
                                                10 to 30 grams
                                                (g) of
                                                lasalocid per
                                                ton; or add at
                                                the rate of 0.5
                                                to 2.0 lb/head/
                                                day a medicated
                                                feed (liquid or
                                                dry) containing
                                                0.125 to 1.0 mg
                                                melengestrol
                                                acetate plus 50
                                                to 720 mg
                                                lasalocid/lb to
                                                a ration of
                                                nonmedicated
                                                feed to provide
                                                0.25 to 0.5 mg
                                                melengestrol
                                                acetate and 100
                                                to 360 mg
                                                lasalocid/head/
                                                day.
                                               Lasalocid
                                                provided by No.
                                                046573 in Sec.
                                                 510.600(c) of
                                                this chapter.
(iv) 0.25 to   Lasalocid     Heifers fed in    To administer     000009
 0.5            100 to 360    confinement for   0.25 to 0.5 mg
                plus          slaughter: As     melengestrol
                tylosin 90    in paragraph      acetate plus
                              (e)(1)(i) of      100 to 360 mg
                              this section;     lasalocid plus
                              and for reduced   90 mg tylosin/
                              incidence of      head/day:
                              liver            1. Add 0.5 to
                              abscesses.        2.0 lb/head/day
                                                of a liquid or
                                                dry medicated
                                                feed containing
                                                0.125 to 1.0 mg
                                                melengestrol
                                                acetate/lb to a
                                                medicated feed
                                                containing 10
                                                to 30 g
                                                lasalocid and 8
                                                to 10 g tylosin
                                                per ton; or
                                               2. Add 0.5 to
                                                2.0 lb/head/day
                                                of a liquid or
                                                dry medicated
                                                feed containing
                                                0.125 to 1.0 mg
                                                melengestrol
                                                acetate plus 50
                                                to 720 mg
                                                lasalocid/lb to
                                                4.5 to 18 lb of
                                                a dry medicated
                                                feed containing
                                                10 to 40 g
                                                tylosin per
                                                ton; or
                                               3. Add 0.5 to
                                                2.0 lb/head/day
                                                of a dry
                                                pelleted
                                                medicated feed
                                                containing
                                                0.125 to 1.0 mg
                                                melengestrol
                                                acetate (from a
                                                dry Type A
                                                article), 50 to
                                                720 mg
                                                lasalocid, and
                                                45 to 180 mg
                                                tylosin/lb to a
                                                ration of
                                                nonmedicated
                                                feed.
                                               Lasalocid
                                                provided by No.
                                                046573 and
                                                tylosin as
                                                tylosin
                                                phosphate by
                                                No. 000986 in
                                                Sec.
                                                510.600(c) of
                                                this chapter.

[[Page 426]]


(v) 0.25 to    Monensin 50   Heifers fed in    ................  000009
 0.4            to 360        confinement for  Add at the rate
                              slaughter: As     of 0.5 to 2.0
                              in paragraph      lb/head/day a
                              (e)(1)(i) of      medicated feed
                              this section.     (liquid or dry)
                                                containing
                                                0.125 to 0.80
                                                mg melengestrol
                                                acetate/lb to a
                                                feed containing
                                                5 to 30 g
                                                monensin per
                                                ton; or add at
                                                the rate of 0.5
                                                to 2.0 lb/head/
                                                day a medicated
                                                feed (liquid or
                                                dry) containing
                                                0.125 to 0.80
                                                mg melengestrol
                                                acetate plus 25
                                                to 720 mg
                                                monensin/lb to
                                                a nonmedicated
                                                feed to provide
                                                0.25 to 0.40 mg
                                                melengestrol
                                                acetate and 50
                                                to 360 mg
                                                monensin/head/
                                                day.
                                               Monensin
                                                provided by No.
                                                000986 in Sec.
                                                 510.600(c) of
                                                this chapter.
 (vi) 0.25 to  Monensin 50   Heifers fed in    ................  000009
 0.4            to 360        confinement for  Add at the rate
                              slaughter: As     of 0.5 to 2.0
                              in item           lb/head/day a
                              paragraph         medicated feed
                              (e)(1)(i) of      (liquid or dry)
                              this section;     containing
                              and for the       0.125 to 0.80
                              prevention and    mg melengestrol
                              control of        acetate/lb to a
                              coccidiosis due   feed containing
                              to Eimeria        10 to 30 g
                              bovis and E.      monensin per
                              zuernii.          ton; or add at
                                                the rate of 0.5
                                                to 2.0 lb/head/
                                                day a medicated
                                                feed (liquid or
                                                dry) containing
                                                0.125 to 0.80
                                                mg melengestrol
                                                acetate plus 25
                                                to 720 mg
                                                monensin/lb to
                                                a nonmedicated
                                                feed to provide
                                                0.25 to 0.40 mg
                                                melengestrol
                                                acetate and
                                                0.14 to 0.42 mg
                                                monensin/lb
                                                body weight, up
                                                to 360 mg
                                                monensin/head/
                                                day.
                                               Monensin
                                                provided by No.
                                                000986 in Sec.
                                                 510.600(c) of
                                                this chapter.
(vii) 0.25 to  Monensin 50   Heifers fed in    To administer     000009
 0.5            to 360 plus   confinement for   0.25 to 0.50 mg
                tylosin 60    slaughter: As     melengestrol
                to 90         in paragraph      acetate to 50
                              (e)(1)(i) of      to 360 mg
                              this section;     monensin plus
                              for the           60 to 90 mg
                              prevention and    tylosin/head/
                              control of        day:
                              coccidiosis due  1. Add 0.5 to
                              to E. bovis and   2.0 lb/head/day
                              E. zuernii; and   of a liquid or
                              for reduced       dry medicated
                              incidence of      feed containing
                              liver abscesses   0.125 to 1.0 mg
                              caused by         melengestrol
                              Fusobacterium     acetate/lb to a
                              necrophorum and   medicated feed
                              Actinomyces       containing 5 to
                              (Corynebacteriu   30 g monensin
                              m) pyogenes.      and 8 to 10 g
                                                tylosin per
                                                ton; or
                                               2. Add 0.5 to
                                                2.0 lb/head/day
                                                of a liquid or
                                                dry medicated
                                                feed containing
                                                0.125 to 1.0 mg
                                                melengestrol
                                                acetate plus 25
                                                to 720 mg
                                                monensin per
                                                pound to 4.5 to
                                                18 lb of a dry
                                                medicated feed
                                                containing 10
                                                to 40 g tylosin
                                                per ton; or
                                               3. Add 0.5 to
                                                2.0 lb/head/day
                                                of a liquid or
                                                dry medicated
                                                feed containing
                                                0.125 to 1.0 mg
                                                melengestrol
                                                acetate (from a
                                                dry Type A
                                                article), 25 to
                                                600 mg
                                                monensin, and
                                                45 to 180 mg
                                                tylosin/lb to a
                                                ration of
                                                nonmedicated
                                                feed.
                                               Monensin and
                                                tylosin as
                                                tylosin
                                                phosphate
                                                provided by No.
                                                000986 in Sec.
                                                 510.600(c) of
                                                this chapter.

[[Page 427]]


(viii) 0.25    Oxytetracycl  Heifers fed in    Add at the rate   000009
 to 0.5         ine 75        confinement for   of 0.5 to 2.0
                              slaughter: As     lb/head/day a
                              in paragraph      medicated feed
                              (e)(1)(i) of      (liquid or dry)
                              this section;     containing
                              and for           0.125 to 1.0 mg
                              reduction of      melengestrol
                              liver             acetate/lb per
                              condemnation      pound to a feed
                              due to liver      containing 6 to
                              abscesses.        10 g
                                                oxytetracycline
                                                per ton; or add
                                                at the rate of
                                                0.5 to 2.0 lb/
                                                head/day a dry
                                                medicated feed
                                                containing
                                                0.125 to 1.0 mg
                                                melengestrol
                                                acetate plus
                                                37.5 to 150 mg
                                                oxytetracycline/
                                                lb to provide
                                                0.25 to 0.5 mg
                                                melengestrol
                                                acetate and 75
                                                mg
                                                oxytetracycline/
                                                head/day.
                                               Oxytetracycline
                                                as provided by
                                                No. 066104 in
                                                Sec.
                                                510.600(c) of
                                                this chapter.
(ix) 0.25 to   Tylosin 60    Heifers fed in    To administer     000009
 0.5            to 90         confinement for   0.25 to 0.5 mg
                              slaughter: As     melengestrol
                              in paragraph      acetate with 60
                              (e)(1)(i) of      to 90 mg
                              this section;     tylosin/head/
                              and for reduced   day:
                              incidence of     1. Add 0.5 to
                              liver abscesses   2.0 lb/head/day
                              caused by F.      of a liquid or
                              necrophorum and   dry medicated
                              Actinomyces       feed containing
                              (Corynebacteriu   0.125 to 1.0 mg
                              m) pyogenes.      melengestrol
                                                acetate/lb to a
                                                medicated feed
                                                containing 8 to
                                                10 g tylosin
                                                per ton; or
                                               2. Add 0.5 to
                                                2.0 lb/head/day
                                                of a liquid or
                                                dry medicated
                                                feed containing
                                                0.125 to 1.0 mg
                                                melengestrol
                                                acetate/lb to
                                                4.5 to 18
                                                pounds of a dry
                                                medicated feed
                                                containing 10
                                                to 40 g tylosin
                                                per ton; or
                                               3. Add 0.5 to
                                                2.0 lb/head/day
                                                of a liquid or
                                                dry medicated
                                                feed containing
                                                0.125 to 1.0 mg
                                                melengestrol
                                                acetate (from a
                                                dry Type A
                                                article) plus
                                                45 to 180 mg
                                                tylosin/lb to a
                                                ration of
                                                nonmedicated
                                                feed.
                                               Tylosin as
                                                tylosin
                                                phosphate
                                                provided by No.
                                                000986 in Sec.
                                                 510.600(c) of
                                                this chapter.
------------------------------------------------------------------------

    (2) [Reserved]

[42 FR 28535, June 3, 1977, as amended at 46 FR 18967, Mar. 27, 1981; 49 
FR 39842, Oct. 11, 1984; 50 FR 1843, Jan. 14, 1985; 50 FR 16228, Apr. 
25, 1985; 51 FR 7398, Mar. 3, 1986; 51 FR 36222, Oct. 9, 1986; 52 FR 
2685, Jan. 26, 1987; 52 FR 33804, Sept. 8, 1987; 53 FR 27959, July 26, 
1988; 55 FR 31828, Aug. 6, 1990; 57 FR 5053, Feb. 12, 1992; 59 FR 41241, 
Aug. 11, 1994; 60 FR 11028, Mar. 1, 1995; 62 FR 8373, Feb. 25, 1997; 62 
FR 14304, Mar. 26, 1997; 63 FR 27845, May 21, 1998; 63 FR 41191, Aug. 3, 
1998; 63 FR 66018, Dec. 1, 1998; 67 FR 47688, July 22, 2002]