Primary ciliary dyskinesia in Newfoundland dogs

Primary ciliary dyskinesia was diagnosed in three Newfoundland dogs with hi stories of chronic rhinitis and bronchopneumonia from an early age, Thoraci c radiographs of two of them showed severe, dependent bronchopneumonia and right displacement of the cardiac apex but normal positioning of other orga ns. Histopathological examination of sections of lung from the other dog sh owed severe bronchopneumonia. A semen sample from one dog had a high percen tage of spermatozoa with abnormal tails and poor progressive motility. Tran smission electron microscopy of nasal brushings from all three dogs showed consistent ultrastructural defects in the cilia, including an absence of ou ter and inner dynein arms, disorganisation of peripheral doublets, occasion al supernumerary doublets and singlets, and consistently disorganised basal bodies and foot processes; sections of trachea from one dog also had disor ganised basal bodies. Pedigree analysis was consistent with a monogenic aut osomal recessive pattern of inheritance for the defect. One dog is still al ive, one dog died aged five years two months, and one dog was euthanased ag ed nine months. This is the first time primary ciliary dyskinesia has been reported in Newfoundland dogs.