I had a bad experience I will share. I posted this at that time and got in trouble with the Ai company.   Do not assume your are going to get 60 percent Ai on syncs that's just what they tell you that most people get they should say that's what some people get.  That year AI wrecked my cow herd

The issue is the cows that do not get Ai settled. Many came in the next heat and overwhelmed my yearling bull as well as some cows not coming back in heat for two more months with all the drugs they use. Best success is AI in the winter at very cold days is where they are getting that 60 percent pencil out the costs of the ones that do not get Ai bred add it to those good calves some will be surprised

I had worked as a hired man on a 300 head sync summer dairy herd

After a very good well experienced Ai tech bred them in one day

The older gentlemen that owned the heifers asked how many bull he needed to clean up. I remember they told him to buy 8 bulls

 Rotate yearling bulls a week at a time you get more use out of them