Ipf
I totally respect you opinions in almost all matters, so I say the following as an invitation to sincere debate.
I would take exception to that study on several levels.
Trimming beaks as suggested by show poultry breeders, I believe, is quite different than beak trimming by commercial poultry producers.
So called debeaking in the commercial industry is sever and the birds do not have the opportunity to re-sharpen their own beaks. This is a cruel practice, in my opinion , studies like this are very well intentioned, wanting to bring attention to this cruel practice. I wholeheartedly agree and am against debeaking.
However what is suggested here is a much more passive approach and the birds should be allowed the opportunity to resharpen their beaks.
Imagine trying to get rid of lice and mites with short blunt beak. Not nice at all, but short smooth sharp beaks would work very well, better in fact I imagine than long overgrown sharp beaks.
As an animal advocate it troubles me to have to question a well intended study, but as with all studies it must stand up to scrutiny.
I believe small cages and debeaked birds live a horrible existence but we must really understand what is the the problem.
For us:
A well trimmed beak is good.A sharp beak is very good for grooming and visually nice.
For commercial producers with birds in tight quarters:
a blunt beak is good as birds don't pick at each other (but for the birds, its uncomfortable, and hard to groom properly and control parasites.)
Ultimately we need to ask what is best for the bird.
We all know commercial breeders rarely ask this question.
My opinions on the subject.