There's a lot of personal feeling here and not really any evidence
There's also personal experience, which is not quite the same as mushy 'feeling'. I have not been able to find a study giving the healing times for the tails of docked puppies compared to adult dogs, so I am thrown back on personal observation. If the evidence you're shown is at odds with your own experience and observation, of course you question it.
you're using selected parts of an unpublished thesis to back up some of your inferences and yet happily disbelieving other parts of the same thesis that don't 'chime with your experience'. As I've said, cognitive dissonance is a powerful thing.
- Unpublished does not mean wrong. A completed and approved thesis has jumped through several hoops, and its author will have responded to criticisms made of it. Besides, it seems that most of this data has been published (see below - I say seems as I do not have access to the full papers whose abstracts repeat numbers I found in the original work).
- 'using selected parts that back up your inferences'. Well, so have you. You agree with the conclusions of Lederer's Section 4 (in its form as an academic paper). You're happily disbelieving Section 3.
I have no agenda here except what is best for animal welfare
Ditto. I am not a breeder. I do not belong to the BASC or any similar body. I am not a member of the Countryside Alliance.
you've said yourself that you're not convinced by Lederer's numbers, so its starting to appear as if your experience sides with selected bits of a single unpublished study that you've cherrypicked, whilst remaining unconvinced by the published data.
I'm not convinced by the '320' number, no. That's the number that you have used, whilst ignoring the data earlier in the study, which seems to be the source material for Lederer et al, 'Survey of tail injuries sustained by working gundogs and terriers in Scotland', Veterinary Record 2014). I say 'seems' as I can only access the abstract, which doesn't have the full reference.
I've outlined the impacts of docking quite clearly
Can you tell me what percentage of dogs docked as puppies suffer from chronic pain, perineal hernias and incontinence? Until you can, then the impact of docking is not 'clear'. We need that data to allow us to decide if the negative consequences of docking outweigh the positive consequence of the reduction in tail injuries in adult dogs. (We would also need data on pain levels and healing times for the docking of puppies and amputation of tails in adult dogs.)
what are these other longterm impacts of not docking? (with the exception of tail injury which we've already discussed)
I didn't say there were 'other longterm impacts'. I think the rate of tail injury in adult spaniels and HPRs is quite enough of a impact.
The Lederer numbers that you asked for:
On page 31-32 of [[http://theses.gla.ac.uk/5629/1/2014lederermvm.pdf) the study I refer to]] , Lederer gives statistics for tail injuries reported in docked and undocked working dogs. To simplify it here (since you can't tabulate data on MN), I'll just use her numbers for spaniels and omit the HPRs:
Undocked dogs in sample: 243
Undocked dogs with tail injury: 135 (55.6%)
% tail-injured dogs taken to vet: 36.4%
Number of tail injured dogs taken to vet: 49 (my calculation: 36.4% of 135)
% of undocked spaniels in sample taken to the vet in one year with a tail injury: 20.1% (my calc again: 49 as a % of 243).
Elsewhere in this study, Lederer concludes that 20% of tail injured dogs who are taken the vet end up with amputations; other studies put the figure higher (Diesel et al, which I think I mentioned earlier, puts it at 30%). Now, 20% of 20% who went to the vet is 4% of the total number; 30% of 20% is 6%. So around 5%. In one year. Unfortunately the Lederer study gives no figure for amputations.
I'd still love for someone to explain to me how cutting off puppies tails is 'preventing injury',
You dock the puppy. It has a much reduced likelihood of injuring the docked tail compared to an undocked dog. One injury, maybe one-and-a-bit.
You do not dock a puppy. If the rate of tail injuries is as high as the Lederer study says it is, virtually every working spaniel or HPR will suffer repeated tail injuries. Many injuries.
Its also worth noting that there are significant potential biases in Lederer's study - many of which she acknowledges herself.
Lederer expressed concern in her study that dog owners would have responded because their dogs had suffered tail injuries. So, as part of the study, she obtained responses to her questionnaire from a group of 'non-responders'. They reports levels of tail injury almost equal to that reported by the original respondents (see Table 3.7 on pp. 41-42 - I have given the link in this post already).
As you say, cognitive dissonance is a powerful thing. I would hope that I am on the alert for it.