first off i dont care what breed you use, i think it has to do with individuals. My expreinces this last year are one 50 acre pasture mostly open with 24 3rd to 5th calfer pairs. First off turning a yearling red sim bull out the idea was to turn the yearling out for 30 days then pull him and put another 6 yr bull in but this young guy even wore me out he herded them, sorted them, was constantly moving them around in 2 seperate groups i told my dad that i could tell which ones he breed by him staying with the group he that started out bigger and got smaller and smaller by the end of 35 days he was laying under a shade tree away from the cows i told my dad theres no need to bring that other bull over to this pasture this guy has got it done! so finally after convicing my dad we ultra sounded this group another 40 days later which is earlier that we ussually do and ill be that yearly had every one of those cows bred in that first 35 days.
good bull
same year different pasture 150 acres about half timber 19 first calf heifers pairs and 6 older pairs turned out one yearling red angus bull then 35 days later turned out a 5 yr black angus bull for anther 35 days. After untra sounding them 8 are for sure the red angus bulls and a few right on the line so this spring we may find out more but lots of stuff can make the difference maybe its the cows? maybe its the pasture? hard to say for sure the funny thing is now that the bulls are up in the lot the red angus bull wipps all of the others incuding the 5 and 6 yr bulls. One of those things... might have got a little off subject but i had to share