The attached paper describes a preliminary study done at the Faculty of Veterinary Medicine of The University of Helsinki at the request of and in collaboration with The Finnish Pug Club. The study aimed to determine whether aspects of clinical history and symptoms or other evaluations could differentiate between dogs identified by their owners as 'good' or 'bad' breathers. It is a small study - 20 Pugs in total - but the findings are interesting and have been used by the Finnish Pug Club and the Finnish Kennel Club (FKK) to inform work on health issues in this breed.
In this study, although essentially all Pugs had observable breathing sounds, the loudness of the sounds and how well dogs did on a walking test seemed to separate the good and bad breathers quite well. The conformation of the nares was not predictive of owner-reported breathing status.
As part of helping IPFD and DogWellNet.com in assembling information on The Brachycephalic Issue, the FKK has shared the attached document (below). We hope to have further information soon, including, e.g., further studies, as well as, breeding strategies and health requirements for Finnish Pugs and other brachycephalic breeds.
Finland Pug Study 2012.docx (English translation)
Link to Finnish report - Mopsi_1_2015_tutkimus.pdf