• If you are having problems logging in please use the Contact Us in the lower right hand corner of the forum page for assistance.

Estrus synchronization

Help Support Ranchers.net:


Well-known member
Jul 16, 2011
Reaction score
The Dakotas
Sorry if this is a dumb question, but has anyone synchronized heifers and only turned bulls out, not AIing. Maybe this is a futile idea, just thought I would see if there is any merit to this.
Yes, I give a single shot of Lutalyse the day I put bulls in with them, and it has worked good. Just make sure you have enough bull power for the first few days. I usually take the extra bulls out after 5 or so days, and put them in with cows... usually there are a few casualties in the cow group by that time :roll: .
Yep-- I've done it too- with about 75% of the calves then being born during the first week of calving...
What kind of cow to bull ratio are you using during the "busy" time? Do you put the cattle in a smaller pasture than usual?
You can also turn the bulls out for 5 days and then give Lutalyse. It won't abort anything that has been bred in that short amount of time and you can pretty much run at a normal ratio but you might have to adjust depending on your acreage, etc.
I'm glad this subject was brought up. My neighbors think I am crazy when I suggest doing this.
I need some clarification from those in the know. When you give the lut shot at bull turnout. It only affects those with a CL and nobody else, right? So the bulls will start breeding those who are already cycling and in a short period those who were regressed will be back into estrus qucker. How soon do they come back into heat?

For those of you who do this how tight does it make the calving season on heifers? Say if I breed 100 heifers what is the percentage that will calve together. I guess what I am wondering will it tighten them like a timed AI service. Does it seem to allow more of them gettng bred. I only breed heifers for 30 days already but I am intrigued by this.

Also on a 100 heifers how many bulls would you need? I already put 5-6 yearling bulls on that many heifers. How many more would I need at the beginning?

Thanks for answering my ?'s


Latest posts