for working spaniels it is not just for looks.
i'll admit however there is no reason for pet and show dogs to be docked, as many docked gundog breeds that hail from the ring have for many generations had the desire to actually work bred out of them, and while docking the tail can remove the risk of non hunting accidents for the resulting limp and curved tail i feel that even that can be fixed up with a breeding plan..... but aside from that the procedure is simple.
the english kennel club has taken a similar approach, pretty easy to police with working spaniels and terriers as the work/show split is there.
hpr's were a bit harder but they have rules for shows which mean those dogs that are docked under the working rule can't be shown in shows that charge an admission fee.
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