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 2 weeks before MGA feeding starts. Best synchronization results occur on heifers that are tract scores 3's, 4's and 5's. It's recommended that 50 percent or better be 4's and 5's meaning they've had a least one heat period.
  • The most popular synchronization system is to feed .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 2 to 5 days later.
  • Feeding .5 milligrams of MGA isn't very much so make sure your feed supplier puts the proper amount in the batch. Use three or four 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 two 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 .5 milligrams of MGA.
  • After the 14 days of MGA, continue the original ration through the AI period.
  • Use a 1 1/2 inch 18 gauge needle for the prostaglandin. Give it in the morning.