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Mike Clough

ES_John_Doe_210H-214W

B.Sc. (Honours) Thesis

(PDF - 19 Mb)

Ungulates in the wild are normally free from periodontal disease. Yet, Cape Breton Highland (CBH) moose (Alces alces andersoni) of Nova Scotia have displayed an increased incidence of incisoform macro and micro fractures, which may have an effect on moose longevity. This condition appears to be rare, as it has only been formally documented in Alaskan (1990) moose (Alces alces gigas) and in Manitoban moose (Alces alces andersoni), and remains unexplained.

We have selected suites of broken and healthy teeth from the CBH and compared them with moose teeth from Shelburne County, NS, where no incidence of broken incisorform teeth has been documented. Fracture patterns in teeth, and especially tooth enamel (hydroxyapatite) were studied under the petrographic microscope and the electron microprobe. Enamel was carefully isolated from 25 representative samples of teeth from both the CBH and the control area and analyzed chemically by Inductively Coupled Plasma Mass Spectrometry (ICP MS).

Samples from the problematic CBH area are significantly depleted in Barium, Lead, Strontium, Cobalt and Tin in comparison with those of the control area, and some of these deficiencies have been associated with dental disease in animals elsewhere. Samples from the CBH were divided arbitrarily into two groups: A) those collected north of the CBH National Park, and B) those collected south of the Park. In each case, they were separated with respect of their perceived low, medium and high degree of fracturing. Correlation trends based on Breakage score and elemental concentration Within the CBH the results are not always consistent. A) North of the Park increased degree of fracturing correlates positively with contents of Cd, Mn, Nb, Rb, Sr, Y, Sn and Bi, and negatively with Al, Cu, Ti, Zn, Mg, As, Th and U. B) South of the Park increased degree of fracturing correlates positively with Ba, Mn, Sr, Mg, Se, As, Y, Th and U, and negatively with Al, Cr, Cu, Ga and Sn. Undoubtedly the number of samples is so far insufficient to draw useful conclusions, yet these are the first data available for moose teeth in the region, and raise interesting questions.

Based on results for tin, where higher concentrations are found within the control group, and the geology of the control area characterized by natural concentrations of tin, it is possible to determine the origin (where a moose lived) based on tooth geochemistry.

Keywords:
Pages: 101
Supervisor: Marcos Zentilli