Inbreeding again

This Autumn co-efficients of inbreeding in Glen of Imaal Terriers has been a recurring subject. “Cat Amongst The Pigeons” certainly caused thought and today Malinka Lingmont gives her take on the subject:-

The articles on the blog about the loss of genes and how to avoid this were very interesting. But does anyone realise that the situation in Glens is already critical? These days it is hard to find a litter with an inbreeding percentage less than 15%. Recently litters have been born whose inbreeding percentage was about 25% to 34%! I recently noted  the death of a thirteen old dog in the database whose inbreeding percentage was 23%. Suddenly I realized that close breeding has been going on for a very long time! Of course it was very difficult to find out the inbreeding percentage in those days. And therefore closely bred dogs were mated to other closely bred dogs and were also closely related to them. But this cannot be continued for ever! It will ruin the breed after all. Nowadays, with databases at hand, it is so easy to avoid. Test the mating in the data base and the inbreeding percentage shows. If it is too high, be wise and go for another combination. Looking at a three generations pedigree is not enough to check if a combination is safe. The database goes back as far as 10 generations and also includes related animals. In Glens it is almost impossible to find a combination less than 10%. In other breeds this number is considered to be dangerously high! In order to protect our breed for the future we MUST try to make combinations less close.  It is the only way to protect the breed. Don’t we all know what happened to humans who lived in a closed society without “fresh blood” from time to time? Let this not happen to our beloved breed as we have, unlike those humans, no place to go if things go wrong. Accounts on the Zooeasy database are free of charge and available through our website:


19 thoughts on “Inbreeding again

  1. Just an example:
    Carrighglen Big Boy (M) X Highlanders Dream Beluna Blue (F) >>> inbreeding 4,21 % over more than 8 generations.(and both clear!)
    Who can do better?

  2. First let me state, I am not good at math! I’m looking at Claudia Orlandi’s “ABC’s of Breeding”, including COI for Dummies -:). pgs 81″linbreeding beyond the 4th generation has relatively little genetic impact on genes of homozygosity in the offspring. pg 82″ “Common ancestors beind the dam and sire that firs appear in the 5th or 6th generations will have relatively few of their genes duplicated in the offsrping.” Pg 83 ” first cousins 3/3 on grandsire or grandam have a COE of 6.25% and 3.13% on 4/4 ancestor and .078% on 4,4/4,4 ancestor.

  3. I was having a hard time posting the previous, so I didn’t finish my thoughts. I’m at a loss as to whether the data in the original post is arrived at by the same math that Orlandi uses.

  4. We must do as we have done before put a good wheaten dog on Glen bitch or use a wheaten x staffie dog on a glen bitch and breed back. Its been done before and it needs doing again.

    • Steve, you have ably illustrated why this number game doesn’t work with Glens. We are all aware of the “heritage” of the breed but that is never considered when breed co-efficients are talked about which makes the figures rather meaningless


  5. re malinka’s mail. i have been saying the same its like banging head on a wall. i have tried to diversify and my combinations are 8% and 11%. i know it is difficult to outcross because you don’t always get in the first generation what you really want but persevere with the next generation and it will come back if careful. i do not agree with crossing with another breed i think the breed should stay ‘pure’

      • glens from my point of view are being bred and to try and improve but also widen the gene pool. to carry on inbreeding again and again cannot in my view be a healthy result for the breed. i was merely pointing out that by just outcrossing for one generation can lower the co efficients. some may want to do this others may not but if we continue to breed to closely the breed will eventually come to a

  6. The coi is just a number and is meaningless as it includes all ancestors. – you could cross another breed in – theoretically giving a zero coefficient but then on the next generation be back up to 25%.
    A more enlightened approach is to follow the example of racehorse breeding where they give the percentage of named ancestors.

    What matters is tracking lines and knowing which dogs are repeated and where and if possible keeping strains parallel so that they can be mixed judiciously.
    The Glen has a huge problem that stems in some part from the poor histories from some foundation animals shipped around the world. People had closely related dogs – in one case I know sharing all the same back column of the pedigree – but names didn’t indicate this.

    The gene pool is finite and you have to ask what good would outcrossing to another breed do? We have just found the marker for PRA so hopefully that will be eradicated within a few generations but do we really want to risk L-2-HGA, cataracts, PHPV & kindney problems?
    Outcrosses bring the whole package unless you believe the puppy farmer’s mantra that you get the best of both parents.

  7. Sue crossing has been used to keep the Glen game and thats a good thing its worked in the past the “pure” brigade do make me grin look at whats happened to highly inbred breeds that have been bred to look at problems start occuring. When you breed a dog to purely look at you lose what matters as ISDA say brains before beauty and collies are a very good example.
    You couldnt give me a KC border collie or beardie they look and are totally different now so Sue its nothing to do with puppy farming its to do with commonsense look at how the Norfolk horn sheep was bred babk?

    • But if you already have those genes in the glen you would not be doing the cross for the COI but for an attribute you want….. surely selective breeding can still find that attribute in the existing glen population.I have certainly owned glens that were game enough to do their original job.

    • Steve, the more you talk about crosses the more the illustration is made to everybody how “false” some of the COI figures are. You know it, I know it but it is something that’ll keep coming up again and again because it’s the current fashionable thing to have thoughts about…….and Glen people always have thoughts!

  8. Sue what i mean by game are entered dogs not aggressive dogs i dont want dog aggession i want dogs that work are mute and arent frightened of the dark. plenty will go on top but far fewer underground. The %age of top working dogs is very small all the best working lines of wheaten terriers are highly inbred to top working stock best to best. I prefare the wheaten lines in glens some prefare the lakeland lines i laugh when i here the pure lines Liz. I remember a person not all that long ago who could out of the same bitch have a litter of Glens then wheatens Liz knows who i mean.

  9. Malinka – what does AVK mean/stand for on the Zooeasy database?

    I note that the Zooeasy Inbreeding % figure is greater than the KC COI & figures for individual dogs.

    Thank you.

  10. Malinka

    Under ‘Extra Fields’ the Zooeasy database has General Health, Eyes and Patella Luxation.

    Different countries around the world seem to do different tests on their breeding stock … if this is considered an international database, I wonder why Hip scoring (USA & Scandinavia) and Elbow scoring (Scandinavia) is not included in the Zooeasy ‘Extra Fields’ …?

    • Your’ nearly right Allison.
      Basicaly: Te AVK number (average variatoin or variability number) concerns only the parents in a mating and it states the % of “different” ancesters! exempl AVK 91% >> only 9 % of the ancesters in the pedegrees from both parent are common. 91 % are different.
      COI’s coefficients of inbreeding are atributed to the “offspring’ (pups) of a mating.
      But never mind, all this is much too little too late. Many people I know who had glens…have already changed breed. So for those interested,have fun…. putting staffies on glens.

  11. I agree with Stephen we want real vintage glens as vintage as possible, we don’t want cockapoos , showrings ruin a lot of dog breeds. I want a working mans dog who lives in the real world. a real family member. glens are the best breed ever. lets keep it like that. Stephen is the man who knows what he’s talking about, go back to the real roots to keep the breed safe and vintage.

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