Does greater inbreeding always mean poorer health?

[Ann Millington]

According to the Pedigree Dogs Exposed Blog... it doesn't - and I tend to agree!!

 

A lot of work has been done recently on recording in the breed database, the COIs of the entire UK-bred IRWS of 30 yearsl - over 10 generations together with some Irish-bred and other overseas-bred IRWS too. So there is a wealth of information to work with.

As the database is arranged chronologically, litter by litter - with the litter COI and those of its parents, together with health test results of all, it can be seen that the COI bears little relation to the hereditary conditions we have already dealt with and to isolated health problems.

As far as can be seen the distribution of COIs has been constant over the 3 decades with the vast majority being in the 11% - 29% region - too high, for sure and breeders are advised to select mates to bring the inbreeding % down. Howeverone judicious mating can bring even a high COI down to single figures but at what cost to the breed's specific qualities - temperament, type and performance - and health? 

[Ann Millington]

I started this discussion after the whole UK IRWS COI was recorded on the db and observed that the overall picture of COIs had not changed significantly over 30 years.  In the beginning, of necessity it was either breed close or don't breed at all - we only had the Irish imports to breed from.  Aware of the dangers of inbreeding the Genetic Sub-Committee was set up with the help of Gilbert Leighton-Boyce and Professor Geoffrey Witt.

The two life-threatening hereditary diseases were quickly dealt with, but as I have said before not enough cases of other conditions have been reported to make a research project possible (except PPC which is on-going - and not life-threatening.)

I have always believed that inbreeding is a chancey policy, only to be undertaken with care by those who know a great deal about the breed and all the dogs in the background.... and that it is imperrative to 'go out' every few generations.  That has been the mantra for decades (centuries even)  Inbreeding fixes desirable qualities and equally fixes undesirable ones so I was intrigued that more and widespread adverse conditions have not appeared - and sought the opinions of ES

My personal view is 'not to inbreed and to create as much breed diversity as possible'.

The Boxer piece on PDE2 highlighted the problem with inbreeding very well and I hope will spark some recognition among breeders.... who are still VERY difficult to convince....