The Missouri Show-Me-Select Replacement Heifer Program has stimulated producers to implement at least part of the development program with no intention of consigning animals to a replacement heifer sale. Livestock specialist, Eldon Cole, of the University Outreach & Extension Center at Mt. Vernon, Mo., offers producers the following tips for improving heifer synchronization.


  • Have your veterinarian palpate the heifers for a tract score about two weeks before MGA feeding starts. Best synchronization results occur on heifers that have a tract score of 3, 4 or 5. It's recommended that 50 percent or better be 4s and 5s, meaning they've had at least one heat period.
  • The most popular synchronization system is to feed 0.5 milligram of MGA per head per day for 14 days then wait 19 days to inject a prostaglandin into them, then breed on standing heat two to five days later.
  • Feeding 0.5 milligrams of MGA isn't much, so make sure your feed supplier puts the proper amount in the batch. Use 3 or 4 pounds of feed per head per day as a carrier.
  • Pre-feed the identical feed without the MGA to your heifers for at least one week before administering the MGA in the feed.
  • Provide 2 linear feet of bunk space per heifer, and that's just for one side of most narrow troughs.
  • Feed once a day. If heifers are on lush pasture and hesitant to eat, consider dry-lotting them the night before.
  • If after a couple of days you see heifers in standing heat, the animal in estrus probably isn't getting her 0.5 milligrams of MGA.
  • After the 14 days of MGA, continue the original ration through the artificial insemination period.
  • Use a 1-1/2 inch 18-gauge needle for the prostaglandin. Give it in the morning.