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MGA 100 Premix (Canada)

This page contains information on MGA 100 Premix for veterinary use.
The information provided typically includes the following:
  • MGA 100 Premix Indications
  • Warnings and cautions for MGA 100 Premix
  • Direction and dosage information for MGA 100 Premix

MGA 100 Premix

This treatment applies to the following species:
Company: Zoetis

melengestrol acetate premix - mfr. std.

Veterinary Use Only

DIN 00813826

MGA 100 Premix Indications

For growth stimulation, improved feed utilization and suppression of estrus (heat) in heifers fed for slaughter.

Directions For Preparing Medicated Supplements

MGA 100 premix should be thoroughly mixed in a supplement for feedlot heifers at a level that will provide 0.4 mg of melengestrol acetate per head per day. The following chart shows the quantities of MGA 100 premix to be used to prepare various supplements.

Amount of supplement to be fed per head per day

Amount of MGA 100 premix to be added per 1000 kg of supplement

0.25 kg

7.27 kg

0.5 kg

3.64 kg

0.75 kg

2.42 kg

1.0 kg

1.82 kg

Good manufacturing procedures should be observed in preparing supplements containing MGA 100 premix in order to avoid cross contamination of other feeds.

Directions For Use Of Medicated Supplements

Supplements containing MGA 100 premix should be fed at the recommended rate that will supply 0.4 mg of melengestrol acetate per head per day. Such supplements, that are usually designed to be fed at a rate of 0.25 to 1 kg per head per day, may be fed separately, top-dressed on the grain or silage or mixed with the rest of the ration to provide a complete feed. Alternatively, MGA 100 premix may be used in pelletted feeds, including those which contain a lignin sulfonate pellet binding agent.

Medicated supplements should be used continuously throughout the time that the heifers are being fed for slaughter. If medication is stopped for three days or more, the heifers may come into heat. A 24-hour withdrawal period immediately preceding slaughter must be observed; however, longer withdrawal periods should be avoided.


Treated animals must not be slaughtered for use in food for at least 24 hours after the latest treatment with this drug. Do not use in dairy cattle. Do not use in calves to be processed for veal. Keep out of reach of children.


1. Use only in heifers being fed for slaughter.

Not effective in spayed heifers or steers.

2. MGA 100 premix must not be fed to heifers treated with other hormone drugs.

Medicinal Ingredient

Each kg contains:

Melengestrol Acetate

220 mg

1 kg = 2.2 lb = 1000 grams


Store in a dry place to prevent caking.

Zoetis is a trademark and MGA is a registered trademark of Zoetis or its licensors, used under license by Zoetis Canada Inc.

Zoetis Canada Inc., Kirkland QC H9H 4M7



25 kg



CPN: 1198299.6

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