Structural Variation in the Nasal Bone Region of European Moose (Alces Alces L.)

Abstract

The ontogeny of typical (normal) nasal bone region of the European moose (Alces alces L.) and the 3 variants of the pattern, was studied. The variants, named as “extra bone type”, “punctured type” and “open type” referring the morphology of the internasal suture, were originally observed in Finnish male and female moose skulls in 1971. All of the variants were later found in hunting trophy exhibitions presenting male moose trophies from Sweden, Norway, Baltic Republics of USSR and Poland. The frequencies of the variants showed regional differences. By using histological, radiological and OTC bone labelling methods, all of the nasal bone types were observed in this study in embryonal (N=36), newborn (N=21), juvenile (N=38) and adult (N=12) moose. Two twin embryos showed different nasal bone structure. The variation is considered to be of congenital origin.

Sammanfattning

Näsbensregionens normala ontogeni och dess tre olika varianter (extraben, ihålig och öppen) studerades hos den europeiska algen (Alces alces L.) med alizarin red S, radiologisk, histologiska och OTC-benfargningsmetoder (N=107). Inga morfologiska skillnader observerades mellan näsbensregionerna av fostrarna samt växande och fullvuxna älg. Tre månader gamla tvillingsfostrarna visade sig vara av olika näsbensregionstyp. Alla näsben hade en ossifikationscenter. Dessutom observerades skiida ossifikationscentra i preparater av extrabenstyp. I öppen typ visade dorsala delar av conchae och septum nasi tecken av reparationsprocess. Variationen tycks vara av medfödd natur.