In-breeding Risk same grandfather & great great grandfather

Help Support CattleToday:

It's anecdotal with the size of herd I have, but my linebred/inbred calves have done well and look good, with the exception of those that had more than 50% influence from any given ancestor, so father/daughter and mother/son matings just seemed to not do well, I have some calves with the a couple ancestors coming up 3 times in their family tree and perform well, take that for what it's worth
 
Lucky, I'll give you that mutations can and do occur, but what sticks out to me in your statement is that you bought that registered Angus bull. I doubt he was the original carrier of that defect, I would guess he inherited it from a parent. A short story, around 1980 I saw a calf out of a registered angus cow that looked like a fawn, I remember thinking it must be proof a buck can serve a cow. Then some thirty five years later, the AAA announces they have discovered a new recessive gene, called fawn calf syndrome, and they have developed a test for it. I'm not sure how to describe my feelings, disappointed or disgusted would come close. I'm sure the defective calf I saw was not the first one, and it took the Association that long to discover it?

I read a book once titled "The Battle of Bull Runts". It described how a bull born in 1899, through a series of events similar to what you describe, became the originator of the dwarf gene that afflicted the Hereford breed some forty and fifty years later. By that point it was impossible to determine whether the defect originated with him or had been inherited. Everyone who calls themselves a cattle breeder should read that book. The AAA has even come up with a process to declare a bull recessive trait free. All you have to do is breed him to a number of his own daughters, thirty two I believe, and if all the resulting calves are normal he can be recognized as such.

The chances of a new recessive syndrome occurring on my farm is approximately the same as winning the lottery, the chances of buying it, of importing a problem, is much higher. What I am doing is not for everyone, but I am happy with the results so far.
 
This thread and a few others have pretty much convinced me to start keeping a bull out of our own cows.

I have found that those who have done a lot of line breeding really don't like to discuss their methods.

We have a CCR Boulder bull out of 1300lb cow that's 10 years old and always has a calf early and has stuck AI every time I have bred her. She looks the same year round whether nursing a calf or eating poor hay. Here she is after nursing a calf for 2 months this fall.

 
Nick,
Your supposition that this bull inherited the SCN defect isn't born out by scientific examination.
This bull we purchased was, as far as we can tell, the originator of the SCN defect; that is, the mutation arose in him. While his dam and sire were not available for testing when the defective gene sequence was characterized, AI sires several generations back were tested, and found to be free of the defect, as was the single half-sib cow remaining in the herd of origin. The bull was by a son of SAF Focus of ER, out of a New Design 878 daughter... well-known genetics to Angus folks, and most of the ancestors in the 4-5 generations behind him had material on file available for testing, and all were found to be free of the SCN defect.

For example, GAR Precision 1680, the Angus bull whose widespread use - putting him on top and bottom of the pedigrees of many Angus cattle back in the late 1990s-2000s - was a double-defect carrier, but only inherited one of those defective genes. 1680 did indeed inherit the AM (curly calf defect) from ancestors, but he himself was the 'founder' of the NH (Neuropathic Hydrocephalus) defect... the mutation that caused NH occurred in him.

I have retained and used home-bred bulls in the past with decent results, and some were pretty intensely linebred back to a specific bull, but mutations can and do occur, and just because you've bred an animal's ancestors for multiple generations, doesn't mean a deleterious gene mutation can't rear its ugly head and spread widely for several generations before two carriers happen to mate and it reveals itself.
 
Sounds like you've done your homework, and well, Lucky. I didn't start down this path without doing some of my own research and reflecting, and am well aware of the stigma and risks involved, but I'm far enough along now that I can let the results speak for themselves. My only regret is that I didn't start sooner.

Kentuckyguy, you're right, few will publicly admit to inbreeding, on purpose anyway, and that mindset is what allows recessive genes like curly calf syndrome to quietly spread until the gene is so pervasive that it can't be kept hidden. Just like dwarfism did a hundred years earlier. Somehow, the lesson wasn't learned that inbreeding will expose any flaws present and can be a good thing. Instead, what seems to have been the perception is that inbreeding caused dwarfs, a false assumption, which led to the stigma I mention. It was said earlier in this thread about heat in the kitchen, a true statement. I keep one or two bull calves back every year to use, and come breeding season I turn all the bulls out, best bull wins. I think the oldest bull is five, maybe six. If I have any doubts, hints, or suspicions about any bull, he goes to town, quickly. Most of the herd is registered and we send in dna samples to determine parentage on the calves we keep. We are getting close to where I think we need to import new blood and bred two cows AI this summer towards that goal, might do more next year. I'd have to go back to look, but thinking on it now it's been longer than eight years since we started down this path, probably closer to twelve. It was a long road to get here and there is still plenty of room for improvement, but I like the direction we're headed and haven't had any six legged calves yet, did have a red one a few years ago that surprised me though.
 
I read a book once titled "The Battle of Bull Runts". It described how a bull born in 1899, through a series of events similar to what you describe, became the originator of the dwarf gene that afflicted the Hereford breed some forty and fifty years later. By that point it was impossible to determine whether the defect originated with him or had been inherited. Everyone who calls themselves a cattle breeder should read that book. The AAA has even come up with a process to declare a bull recessive trait free. All you have to do is breed him to a number of his own daughters, thirty two I believe, and if all the resulting calves are normal he can be recognized as such.

The chances of a new recessive syndrome occurring on my farm is approximately the same as winning the lottery, the chances of buying it, of importing a problem, is much higher. What I am doing is not for everyone, but I am happy with the results so far.
Nothing new about breeding a bull back to his daughters to prove him clean, it's an old standard used for years,
 
Yep; it's not new. Before the advent of gene testing, sire-daughter matings were the norm for 'proving' genetic-defect free status.
Identical, for all intents and purposes to the breeding scheme for establishing homozygous polled status, though you don't have to have daughters - breed a polled bull to 35 horned cows... if all offspring are polled, there's a 95+% likelihood that the bull is homozygous polled.
 
The nut that runs his cows on my place has been doing that for about eight years now, keeping a couple of his own bull calves to use every year. If you have any hidden genetic flaws or defects, they will emerge, but the calves here hit the ground running and grow like weeds. Biggest problem I've seen was a cow had a huge 140 lb calf that was dead by the time we got it pulled out, her son was one of the bulls who had been used the previous year so both went to town. I got tired of importing problems, and the calves seem to get better every year.
when we used good bulls out of our best cows.....it moved our herd ahead.....this was a registered angus herd and in the beginning all the cleanup bulls were sons of AI bulls....and out of our top cows...eventually we had calves from our bulls that were outperforming the calves from the AI bulls.
 

Latest posts

Top