title: Comparison of direct versus radiographic measurement of sagittal otoliths in cadavers of bogue (Boops boops).
abstract: OBJECTIVE
  To validate the use of radiography to determine the length of sagittal otoliths in intact bogue (Boops boops; a sparid fish [commonly called sea bream]).
  
  
  METHODS
  52 bogue cadavers.
  
  
  METHODS
  Weight and standard lengths (from the tip of the snout to the caudal end of the last vertebra) of fish were measured. The radiographic beam was centered over the postorbital area, and images were obtained via ventrodorsal, 30° right dorsal-left ventral oblique, and 30° left dorsal-right ventral oblique projections. Otoliths were removed from the fish; sagittae were measured directly and on radiographic images by use of a vernier caliper. The relationship between direct and radiographic measurements of sagittal otoliths was calculated.
  
  
  RESULTS
  Paired sagittal, lapillus, and asteriscus otoliths were identified. Sagittal otoliths were comma-shaped on ventrodorsal projections; in oblique projections, they appeared ovoid and pairs of otoliths were located in the same dorsal plane. Radiographic length of sagittal otoliths was significantly correlated with directly measured length, and radiographic measurements were not significantly different between ventrodorsal and oblique radiographic projections.
  
  
  CONCLUSIONS
  Radiographic examination of sagittae was useful to determine the length of sagittal otoliths and, consequently, the fish length. In ecological applications, the radiographic measurement of sagittal otolith length may be useful for studies on the aquatic diet of organisms (fish, pinnipeds, and marine birds) because it allows for quick back-calculation to the size of prey.
authors.affiliation: Department of Veterinary Public Health, Faculty of Veterinary Medicine, University of Messina, Polo Universitario dell'Annunziata, Italy. framac@alice.it
authors.forename: Francesco
authors.initials: F
authors.lastname: Macrì
authors.forename: Teresa
authors.initials: T
authors.lastname: Bottari
authors.forename: Rossella
authors.initials: R
authors.lastname: Bonfiglio
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Rapisarda
authors.forename: Fabio
authors.initials: F
authors.lastname: Marino
mesh_terms: D000818:Animals; D002102:Cadaver; D010037:Otolithic Membrane / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D011859:Radiography / Q000662:veterinary*; D021541:Sea Bream / Q000033:anatomy & histology*; D012886:Skull / Q000033:anatomy & histology / Q000000981:diagnostic imaging