title: Histomorphometric and angiographic analysis of the humerus in pigeons.
abstract: OBJECTIVE
  To identify the vascular supply and resorption/formation activity of the humerus of pigeons.
  
  
  METHODS
  Pigeons were injected with the fluorochrome label oxytetracycline and, 5 days later, with the label calcein. 5 days after administration of the second fluorochrome, a wing from each bird was infused with a microparticle barium solution immediately after euthanasia and the chosen humerus was prepared for angiography while the opposite was prepared for histomorphometry.
  
  
  METHODS
  17 nine-month-old pigeons, consisting of 9 male and 8 female birds.
  
  
  METHODS
  At euthanasia, 1 wing was chosen for infusion and the barium solution was injected through a catheter in the brachiocephalic artery. Both humeruses were harvested. The infused humerus was decalcified, radiographed, and sectioned for H&E staining. The opposite humerus was sectioned and measured by use of a morphometric analyzing system to determine cross-sectional area, endosteal and periosteal perimeters, and percentage of perimeter containing a single and/or double label.
  
  
  RESULTS
  All pigeons had an intramedullary arterial supply. The bones had a quiescent appearance histologically, consisting principally of lamellar bone with few osteospecialized cells, resorption surfaces, or osteons. Less than 10% of either the periosteal or endosteal surface acquired a fluorochrome label.
  
  
  CONCLUSIONS
  The intramedullary vascular supply of the humerus is similar in structure to the vascular supply to mammalian bones. The humerus is, however, a quiescent bone in the sexually mature pigeon, with little remodeling activity present.
  
  
  CONCLUSIONS
  The intramedullary blood supply may have an important role in the healing of humeral fractures in avian species.
authors.affiliation: Department of Small Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens 30602, USA.
authors.forename: P G
authors.initials: PG
authors.lastname: West
authors.forename: G R
authors.initials: GR
authors.lastname: Rowland
authors.forename: S C
authors.initials: SC
authors.lastname: Budsberg
authors.forename: D N
authors.initials: DN
authors.lastname: Aron
mesh_terms: D000704:Analysis of Variance; D000792:Angiography / Q000295:instrumentation / Q000379:methods / Q000662:veterinary*; D000818:Animals; D010856:Columbidae / Q000033:anatomy & histology*; D005260:Female; D006811:Humerus / Q000033:anatomy & histology* / Q000098:blood supply / Q000000981:diagnostic imaging*; D008297:Male; D008322:Mammals; D013045:Species Specificity