I've put together some key points from Bet's comments and also some other emails I've had from the Skerritt talk. They make for some grim reading for the future of the breed if his figures hold true. Mr Skerritt, the neurologist based in Chester in the UK, has scanned over 600 cavaliers, more than anyone else anywhere in the world. Here are some notes; someone who attended might add more I hope!
* Of breeder dogs he has scanned now on his low cost scheme over the past three years, he said he has seen an 85%+ affected rate (not sure how he defines 'affected' -- meaning with SM or with the malformation and some protrusion of the brain into the spine) of those that were said by breeders to be completely asymptomatic, presumably clear dogs (195 dogs said to be asymptomatic); only 13% of these 195 were without syrinxes. He has scanned about 600 cavaliers now. Note that breeders who are NOT scanning are breeding dogs they believe do not have SM because they are asymptomatic. This is very worrying at least to me, going by these figures.
* He said he has scanned about two dozen clear/normal dogs of those 600 (one would presumably be my dog Jaspar as he was given a total clear by Mr Skerritt in 2005, but this was before Jaspar was two and wouldn't qualify him as clear under the Rusbridge grading scheme)
* He believes the neurologist breeding recommendations are too broad for the A group (which suggests what he considers breedable dogs would be a severe decrease on those considered breedable now?). Current recommendations:
* He will open his low cost clinic to Brussels griffon breeders as well (they are also starting to show a very high rate of SM)
* He will be publishing on his research
* He thinks cerebellar herniation is very important (this would contrast with some other research in the area)
* He thinks the current popular head shape in the breed has played a role in the spread of SM (a question Iposed by Bet). He noted his colleague Martin Deutschland (who also presented at the London event last year) now thinks a greater height of cerebellum correlates with the increased likelihood of a syrinx developing
* He thinks whelping would be more painful for cavaliers with SM (asked by Bet)
I can't give any more detail or answer any queries on this unfortunately as these are just notes I've gathered from a couple of people. But there's quite a bit there for discussion!