Double M has AI'ed (artificially inseminated) many of their cows for years and years, but last fall Genex asked them to do a progeny test and AI more cows than they normally would. Since all of the fall cows were on Clint's side of the freeway in December, it was easy to ride heat on them for a few days and then synchronize the cows that were left.
The way a progeny test works is Genex asks a ranch to use one reference sire (a bull that's proven and available for general use) and then 3 to 4 young sires (bulls that are newer to the sire line up) and breed cows in a herd to that compilation of bulls. Once the calves are born, the ranch keeps track of all of the data (birthweights, calving ease, weaning weights, yearling weights, etc.) and then Genex tracks the carcasses and all of the data is used to prove the genetic merit of a bull. They like to do progeny tests in bigger herds because it allows for better data statistically because the sample size is larger. That's why we AI'ed more cows than normal, so they'd have a larger sample of calves.
The benefit to Double M is that cows that are artificially inseminted (AI'ed) usually have calves that are more uniform, they calve easier and have calves that grow faster since their genetics are usually superior to calves that are out of the herd bulls.
Double M bred the fall cows to Identity, Chisum, Full Power, Dillon, Pioneer and Final Answer. The calving period for the mature cows that were AI'ed has passed, and so we can safely say that we didn't have to pull anything due to calf size and there is a stout group of fast growing calves out on the meadows right now! Success all around.
If you're interested in using one of the bulls I mentioned above, I've uploaded a set of pictures from each of the young sires and you can click on the links below to look through the first set of calves. The pictures were taken of calves on the first 60 mature fall cows to calve.
For reference, the cows are primarily Angus & Sim-Angus commercial cows that run on irrigated native pasture. Their calves at side were born in mid-late September.