The genetic defect topic has been a hot one here at times so wanted to share this as I know some have been calling for them to do this for years now. I think it is a great move by the AHA to do this in order to be proactive about being transparent with potential carriers and also hopefully forces the hand of some breeders that don't want to DNA test to get their potential carriers tested. Also it provides some protection for buyers that aren't familiar with certain bloodlines or how to properly read a pedigree to have something that alerts them that the animal could be a potential carrier.
So in summary if you register an animal where either 1 of the parents is a known carrier of a genetic defect or there is a gap in pedigree where a carrier exists more than 1 generation back and the next generation(s) was not DNA tested to confirm if they are free of the defect then until that "chain" in progression is broken with an animal in the ancestry testing free of the defect then any animals on down the line with the potential to be a carrier will get this designation until they are DNA tested.
We've been DNA testing all of our sale bulls for many years now regardless if there is a potential defect in their bloodline and had to DNA test several females in our herd a few years back when the MSUD defect came out. We have one 2 year old female sired by a MD carrier bull that at the time MD was not a known defect when we used the bull AI that will surely get the MDP designation and we already plan to get her DNA tested later this year to know if she is a carrier or not. We're a small herd so doesn't take much effort or expense for us to pull some tail hairs or ear tissue when we run cattle through the chute but I imagine any big herds that have progeny out of some of these bulls that are known carriers are going to have a lot of work ahead of them if they haven't already DNA tested their potential carriers.
I would not be surprised if the next move breed associations eventually consider is to require DNA testing for any calf a breeder wants to register. That could be a hot button topic for some as that is another added cost to maintaining a registered herd. AHA DNA testing including the MD test is $55 per head: https://hereford.org/genetics/dna-testing/ I believe the reason why it costs more with the MD test is because currently they have to send the sample off to a different lab that only does the MD testing which is why if you just want the MD test done it's a stand alone $20 test.
So in summary if you register an animal where either 1 of the parents is a known carrier of a genetic defect or there is a gap in pedigree where a carrier exists more than 1 generation back and the next generation(s) was not DNA tested to confirm if they are free of the defect then until that "chain" in progression is broken with an animal in the ancestry testing free of the defect then any animals on down the line with the potential to be a carrier will get this designation until they are DNA tested.
We've been DNA testing all of our sale bulls for many years now regardless if there is a potential defect in their bloodline and had to DNA test several females in our herd a few years back when the MSUD defect came out. We have one 2 year old female sired by a MD carrier bull that at the time MD was not a known defect when we used the bull AI that will surely get the MDP designation and we already plan to get her DNA tested later this year to know if she is a carrier or not. We're a small herd so doesn't take much effort or expense for us to pull some tail hairs or ear tissue when we run cattle through the chute but I imagine any big herds that have progeny out of some of these bulls that are known carriers are going to have a lot of work ahead of them if they haven't already DNA tested their potential carriers.
I would not be surprised if the next move breed associations eventually consider is to require DNA testing for any calf a breeder wants to register. That could be a hot button topic for some as that is another added cost to maintaining a registered herd. AHA DNA testing including the MD test is $55 per head: https://hereford.org/genetics/dna-testing/ I believe the reason why it costs more with the MD test is because currently they have to send the sample off to a different lab that only does the MD testing which is why if you just want the MD test done it's a stand alone $20 test.
