Stupid question re dog breeds

[Tweakie123]

Note I have no skin in this game, I have adopted a rescue dog but just from reading another thread its made my wonder what is the issue with cross breeding breeds? Eg cava poo and other cross breeds. My (very limited gcse) understanding of genetics is that widening of the gene pool would result in healthier dogs not dogs with more issues?

My stance on the whole pedigree v cross breed v mongorel debate is that we need to develop a truly modern, urban dog.

Most dogs were selected for specific traits that involve hunting, guarding or herding. And even Companion breeds are either a waterd down version of the above or have tendency to hyper attachment and separation anxiety.

What we need is a small to medium sized dog that has little prey drive, is happy to be left for 4-6 hours and very sociable with humans and other dogs.
This dog needs to be healthy and robust, suitable for families with primary school aged children. I don't think it needs to be very intelligent as these dogs need more input from their owners or get up to mischief.

I do think that pedigree dogs in the UK suffer from small gene pool and have a lot of genetic defects that need to be addressed. This obviously spills over into any x breeds. The KC does have a lot to answer for.

I love dogs & had them all my life, but I have already made up my mind and will not have another one once my lot (I have 3) is gone. Breeding in the UK is a shambles and I don't want to be part of it... not even for a rescue dog.

Not true. Mutts and street dogs, like feral cats, can average a higher level of inbreeding than either purebred or crossbreeds.

The mutt you refer to is pretty much extinct in the UK. Back in the day if your bitch mated with an unknown dog, you may have kept the biggest, healthiest pup and drowned the rest - so mutts appeared to be v healthy. Now you would would think up an exotic name for them and sell them all for £££. Most dogs are spayed/neutered now so the unexpected pregnancies are far fewer.

@ThePoliteLion I have a Patterdale and agree with @Vroomfondleswaistcoat “don’t do it”. They’re lovely dogs, great characters, mine’s a delight in the house, but a murderous bastard out - I spend an inordinate amount of time walking on windswept moors so we don’t meet other dogs.

It is true.

for my mind its three issues.
firstly the ridiculous prices now charged for what was only a few years ago a mongrel which were often given away free
two the fashion slant when people have tired and go onto the next cross what happens to the previous fashion? yes loads in rescues
thirdly indiscriminate crossing with breeds that really are not ideal crossed together

They can, but they tend not to. Though, of course, someone breeding cockerpoos in a windowless barn somewhere, keeping a puppy and mating her back to her father or uncle will be producing puppies with a very high COI.

It's also worth bearing in mind that genetic COI (based on DNA) can be very much higher than pedigree COI (based on the dog's family tree). This is because canine pedigrees are often incomplete or only go back a few generations. The presumption is made that the dogs at the start of the family tree were not related, but they quite possibly were.

There is scientific research that shows that inbreeding reduces life expectancy at the level of individual dogs. The mutt I met today - according to his owners, basset x saluki x collie x springer (1) - is likely to have a vanishingly low COI. on that basis, he is likely (no guarantees) to have longer life than a dog born of some of the pairings that I rejected a few years ago when we were looking for a puppy - COIs of 25%+.

(1) Collie x springer, or collie x saluki, could well have been a working cross. But basset x anything?