Inbreeding Question

[fitz]

My commercial herd is a mix of simmental and angus. After I use a bull for a while I sometimes decide to start retaining heifers from him. At that point I always replace the bull. If I were to hold a bull calf back from the same bull would I be taking a chance on problems if I were to use this young bull on his half sisters for terminal calves? I guess if they started coming as dinks or less than desireable I would have answered my own question. Thanks for any input or advice.

fitz

 

[Ouachita]

I guess if they started coming as dinks or less than desireable I would have answered my own question. Thanks for any input or advice.

fitz

That would be one way to answer your own question. The other way you would know for sure, is if they unionize.

 

[Red Bull Breeder]

You would be better off breeding the heifers back to there sire.

 

[fitz]

You would be better off breeding the heifers back to there sire.

Thanks RBB. Will be using my old Bull on my fall calvers first of the month. I probably will start looking for a replacement Bull. Whatever I get for the older Bull and the calf should be a good down payment.

fitz

 

[brihop]

I know a few people that breed heifers back to sire without problems... but, those inbred calves are all sold, so it never goes any further. However, it seems to me that the "lesser of the 2 inbreeding evils" would be to breed a bull to his half sister, that way there is still only 50% of the sires blood in the mix. When you breed a heifer back to her sire there is 75% of sire blood, making the resulting calves more inbred than the 1/2 brother/sister option. Or am I missing some technical genetic lesson here?

 

[fitz]

I know a few people that breed heifers back to sire without problems... but, those inbred calves are all sold, so it never goes any further. However, it seems to me that the "lesser of the 2 inbreeding evils" would be to breed a bull to his half sister, that way there is still only 50% of the sires blood in the mix. When you breed a heifer back to her sire there is 75% of sire blood, making the resulting calves more inbred than the 1/2 brother/sister option. Or am I missing some technical genetic lesson here?

I read some information on inbreeding from the University of Missouri and OSU after asking the question here.
It listed the coefficient of relationship when mating the parent to offspring or full sibs to one another would be 50% and half sibs to one another would be 25%.
I thought I had read somewhere that mating the half sibs would be O.K. and I think if you had exceptional stock, plenty of time and knew what you were doing you could be successful. I don't qualify in any of the above. After reading further about the possible downsides I think I will continue to change out Bulls. With the mutts I have I can't afford to start heading backwards.
Next spring I will only have two heifers in question and I think I will put them with their sire, sell their calves and move on to the best bull I can find and afford.
Again, I appreciate the help.

fitz

 

[Red Bull Breeder]

The sire is the way i would go you already no what he produces. If he is good enough to retain heifers out of he should be good enough to breed his daughters back to. Unless you have hidden genetic defects you will have no problems.

 

[robert]

the purpose of inbreeding / linebreeding is to fix traits of economic importance or functional desirability with in known population, then take those linebred/inbred bulls and use them as an outcross in a commercial situation to increase consistency and predictability of the offspring. You stated you have a commercial sim/angus herd, there is no earthly reason to inbreed or linebreed within a commercial herd especially if this is to produce a terminal product, all you are doing is shorting yourself on growth/longevity/vigor. Look for a linebred sire of the opposite breed to the one you have been using (buy Angus if the old bull is Simmental and vice-versa) and use him across the herd.

 

[Red Bull Breeder]

He is just trying to use his old bull a little longer Robert.

 

[robert]

He is just trying to use his old bull a little longer Robert.

I understood that, I guess my point was that keeping a son of the bull, unless there's a real compelling reason such as a desire to create a linebred program based upon that sire is just going to short him on actual production within the herd. I would tend to agree with you that simply using the old bull back on his daughters is a far more reliable approach to that than a diluted form through a son. Without doubt though in a commercial situation the next step after those 3/4 inbred daughters would be the opposite breed over them.

 

[Red Bull Breeder]

We are on the same track Robert. Just ran it around the corral a little differently. I wouldn't use the son either.

 

[brihop]

Disclaimer: Everyone knows producing 3/4 inbred daughters is not ideal, but they're just a product of convenience in a small "backyard" herd. That being said, do you guys think that it would be ok to retain these 3/4 inbred heifers? ...as long as they're not bred back again to the same sire. (they could still be good cows, not just instant auction animals)

 

[robert]

I wouldn't see any problem with it personally, depending upon the traits being concentrated by the sire/daughter mating you may or may not see inbreeding depression, for example if sire is a higher growth bull and that is one of the traits you have been selecting for then that should be something that is concentrated in the 3/4 sibs, and while it won't express fully in those sibs it should be obviously evident when you cross them with a different breed as you will have an advantage of concentrated growth genes + hybrid vigor.

 

[fitz]

Yes. Basically, I just wanted to use the Angus bull here for one more fall 2012 and spring 2013 breeding. In reading some earlier threads and the information offered here I was figuring if I retain heifers sired by Angus bulls (be them 1/2 or 3/4 SimAngus) I should consider Simmental for the next bull if I wanted to just stay with the two breeds. What about a SimAngus bullcross for these 1/2 and 3/4 simangus cows? Maybe if i could fine one, a Gelbvieh for terminal calves?

fitz

 

[Red Bull Breeder]

Thats why the sim angus, Balancer and the limiflex are being bred. To keep cross breeding simple. As for retaining the inbred heifers i would not have a problem with keeping those heifers.

 

[fitz]

Yes. Basically, I just wanted to use the Angus bull here for one more fall 2012 and spring 2013 breeding. In reading some earlier threads and the information offered here I was figuring if I retain heifers sired by Angus bulls (be them 1/2 or 3/4 SimAngus) I should consider Simmental for the next bull if I wanted to just stay with the two breeds. What about a SimAngus bullcross for these 1/2 and 3/4 simangus cows? Maybe if i could fine one, a Gelbvieh for terminal calves?

fitz

Here's the young bull I had thought about holding back. He's getting a cleanup by momma in picture. Took him to market today. He was 257 days old and scale weight at sale barn today was 935.
fitz

 

[Red Bull Breeder]

Good calf.