Melengestrol acetate liquid feed mix (MGA) is a synthetic progestin, indicated for use in heifers.
INDICATIONS
- For Heifers in Confinement:
- Increased rate of weight gain (faster growth).
- Improved feed efficiency (getting more weight gain per unit of feed).
- Suppression of estrus (heat), which minimizes restlessness and feed wastage from cycling.
- For Heifers Intended for Breeding (Replacement Heifers):
- Suppression of estrus (heat) to manage reproductive cycles and synchronize breeding.
- In Combination Feeds (with other drugs):
- Can be combined with tylosin for liver abscess control.
- Can be combined with monensin for prevention and control of coccidiosis
ADMINISTRATION
- Feed Premix: MGA is a Type A medicated feed premix.
- Batch Mixing: The premix is thoroughly blended into larger quantities of complete feed or protein/grain supplements.
- Top-Dressing: It can also be top-dressed onto other feedstuffs for daily consumption.
- Dosage: Usually 0.25 to 0.5 mg per head per day, depending on the goal (growth vs. estrus suppression).
for Estrus Synchronization (Heifers):
- MGA-Only: Feed for 14-18 days to suppress heat.
- MGA-PGF2α Protocol: Feed MGA for 14 days, then withdraw; administer Prostaglandin F2α (PGF2α) 17-19 days after MGA withdrawal to induce synchronized estrus.
- MGA-Select (MGA-GnRH-PGF2α): Feed MGA for 14 days, followed by GnRH 10-12 days after withdrawal, then PGF2α 7 days after GnRH for precise AI timing.
- Target Animals: Only effective in intact heifers; not for steers or spayed heifers.
