Pedigree "in line breeding"

[Guiggs]

What's people's thoughts on how closely related is "safe" or "acceptable" when breeding cattle?
From a relatively limited population I've got a cow that shares the same grand dam and another that shares the same great grand sire.
I'm not too concerned about the latter but is the former ok?

 

[crofteress]

well I've a neighbour thinks its ok to have brothers and sisters serving each other, serving their mothers etc etc and all calves are as lively and vigorous as I've ever seen, nothing can kill them, so going by that it seems to work but if I did it they would all come out with two heads

 

[Philip Watkins]

Chillingham wild cattle haven't died out yet and they're all related to each other.

 

[Danllan]

I read a paper many years ago about Cape Buffalo herds, I think it was by Richard Estes, and the amount of inbreeding (or 'line breeding' if you like) was surprising. Surprising in that it was fairly low due to bull movements and turnover. However it was there and I guess it was in amounts significantly higher than in most domestic herds, so you can probably get away with more than you might think. Are you just mix and matching? If so problem, but if you with a breed you might want to find out the society's opinion.

 

[CopperBeech]

I'd have thought that would be absolutely fine. Half brother \ sister should be OK and your miles off!

 

[wellingtonfarmer]

What about purring sire back over his daughters?

 

[Devil's advocate]

In a cross bred I would not be worried, pedigree just need to be careful.

It is not inbreeding that is the problem as said many feral flocks/herds inbred without many problems. It is what you are inbreeding with, in one breed of sheep I get the odd "daft lamb disease" (disease of nervous system, throw there heads back) in another entropic eyelids. Both caused by recessive genes in the wild they would become less common, well the entropic eyelids would. Not so sure about the daft lamb disease very low percentage.

 

[Dry Rot]

Chillingham wild cattle haven't died out yet and they're all related to each other.

Yeah, but they've only been going for 600 years. Can't last!

 

[Dry Rot]

I don't think the great livestock improvers ever published their pedigrees, did they?

 

[GenuineRisk]

Sure I read somewhere that after seven generations of inbreeding, the survivors, if continuing to inbreed, would be genetically pretty sound. Obviously, line breeding is less intensive.

 

[matthew]

Call it 'Line breeding' if it's successful, 'inbreeding' if not.

I saw it once with a chap with Longhorns. His cattle got smaller and smaller until they could almost limbo dance under a gate.

 

[Dry Rot]

I had a genetic problem in a line of dogs I was breeding. So I got the number of a company that bred mice for laboratories and asked to speak to one of their geneticists. (I have a tendency to do that and usually find they are very helpful as it is a break from their routine! All they can say is b...r off!).

Anyway, I asked this guy about inbreeding. He said, they don't consider a line inbred until they've bred brother to sister for 30 generations. Then he added, "Of course, they will only be inbred for the traits we are selecting!"

But mice aren't cattle and, as has been said, it depends what you are selecting for. No doubt, if the longhorn breeder had been selecting for large size, his cattle might have got bigger! Not many racing greyhounds with hip displaysia either as they don't breed from dogs that don't win!

 

[matthew]

But mice aren't cattle and, as has been said, it depends what you are selecting for. No doubt, if the longhorn breeder had been selecting for large size, his cattle might have got bigger! Not many racing greyhounds with hip displaysia either as they don't breed from dogs that don't win!

And it depends IF you were 'selecting' for anything at all, or just too mean to replace the bull.

 

[Archie]

well I've a neighbour thinks its ok to have brothers and sisters serving each other, serving their mothers etc etc and all calves are as lively and vigorous as I've ever seen, nothing can kill them, so going by that it seems to work but if I did it they would all come out with two heads

You mean like this bull we once had?


Described by seller as exceptionally well bred. Didn't realise exactly what he was getting at until we got him home and studied catalogue a bit more closely

 

[bjreroberts]

No "safety" issues, just depends on what you plan to do with the offspring, pedigree value may be affected as might be frowned upon by potential buyers

 

[Guiggs]

The animals I'm referring to are from the "P" type, native population Lincoln Red cattle.
Females will be retained and eventually go to a different bull.as said the closest relative is a grand dam and I have no intention of going any closer than that, the bull will probably only be here for 3 or 4 years as I just wanted to try and do my bit for the breed... time will tell if that is a foolish decision or not!
@Wolds Beef any thoughts?

 

[andybk]

all the most successful breeders in history line bred to an extent (where the hybrid vigour comes from the more closely related the more it will be on an outcross ) , Bakewell with his longhorns and leicester sheep , Elman (southdown sheep) results are still felt today 200+ years later , the key really is a very very strict policy on faults , I was told once by a very old hand if you want to test your genetics breed to a very close relation (mother / sister/ daughter ) if the genetics have problems it will come out in this cross , if ok , you are safe to use him more widely with less fear of problems , I always do this with any new sire here to a limited degree it soon finds out the duffers , and some interesting results with some so called pure rams
It will however reduce the size of the offspring over time , but over an outcross the hybrid vigour will compensate

have a gander at John randalls life story "leather Gaiters and Whattle Hurdles " where he has a chapter on line breeding , very respected shepherd in the south during his life breeding hamps and the like , born and worked local to us here for many years , top breeder and showman of his day always wore his trademark leather gaiters

 

[yellowbelly]

Line breeding/in breeding, call it what you will, exaggerates all the good points but also exaggerates all the bad points, so you just need to cull hard.
Line breed 2 separate lines within the breed for several years and then cross the 2 separate lines - that's the only way you can get any 'hybrid vigour' in a pure breed.