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1.
Ann N Y Acad Sci ; 969: 358-63, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12381618

RESUMO

Ontario has embarked upon a program to restore elk (Cervus elaphus) that were once native to that province. A comprehensive disease-management strategy has ensured that elk are free of infectious diseases such as brucellosis and tuberculosis prior to shipment to Ontario. Postmortem analysis occurs on elk mortalities in Ontario to ensure that elk are not infected with diseases such as chronic wasting disease and tuberculosis. Between 1998 and 2001, a total of 443 elk were transported from Elk Island National Park, Alberta, and released in four different areas of Ontario. Cumulative mortality for elk in all areas was 26% from 1998 to January 2001. The primary causes of mortality were post-release stress-induced emaciation (21%), wolf predation (20%), transport/handling injuries (10%), bacterial infections (10%), and drowning (7%). Female calves had the highest mortality rates (37%) compared to the other sex and age cohorts (23-24%). Preliminary findings suggest an inverse correlation between the length of time elk are held in enclosures prior to release and the distance they disperse from the release site. The 2001 estimated population of elk in Ontario is about 400 individuals.


Assuntos
Controle de Doenças Transmissíveis , Doenças Transmissíveis/veterinária , Cervos , Fatores Etários , Animais , Animais Selvagens , Brucelose/epidemiologia , Brucelose/prevenção & controle , Brucelose/veterinária , Causas de Morte , Doenças Transmissíveis/epidemiologia , Doenças Transmissíveis/mortalidade , Conservação dos Recursos Naturais , Feminino , Masculino , Ontário/epidemiologia , Fatores Sexuais , Tuberculose/epidemiologia , Tuberculose/prevenção & controle , Tuberculose/veterinária , Doença de Emaciação Crônica/epidemiologia , Doença de Emaciação Crônica/prevenção & controle
2.
Environ Pollut ; 113(3): 347-55, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11428143

RESUMO

Ontario's only free-ranging elk herd located at Burwash-French River has been subjected to the influence of historic copper-nickel-iron (Cu-Ni-Fe) ore smelting operations within the Sudbury area. Metal levels in selected body tissues, preferred forage items and fecal pellets were determined, and their potential effects on health and reproductive viability assessed. Significant age effects were apparent in 13 out of 31 tissue metal values obtained, with most age-related differences attributable to elevated concentrations in fetal tissues. Cu and zinc (Zn) levels were four to six times higher in livers and one and a half to two times higher in the bones of fetuses as compared to post-natal animals. Enhanced pre-natal tissue burdens were also noted for cobalt (Co), Ni and lead (Pb) in muscles. However, mean cadmium (Cd) levels in kidney, liver and muscle tissues, as well as hepatic Fe concentrations, showed significant increases with age. Although Cd levels in the kidneys of older elk were still well below the reported threshold for irreversible organ damage, and not considered to be health-threatening, detailed histological study of the cortical tissues for subtle pathotoxicological effects may be warranted. Unlike renal and hepatic tissues, Cd concentrations in skeletal muscle were minimal and within levels considered acceptable for human consumption. Forage species collected in the elk range generally showed higher (two to eight times) Ni and Fe levels than the corresponding plants from a non-contaminated reference site. The highest Ni and Fe burdens were carried by eastern white cedar, a preferred winter food item for elk. No consistent site-related trends were demonstrated by Cu, Zn, Co, Pb, chromium (Cr) and Cd forage levels. Mean metal concentrations in fecal pellets generally exceeded the mean composite forage levels by a factor of 3, except for Ni, which was five times more concentrated in feces. Significantly elevated Ni and Fe levels in preferred browse species and fecal pellets of the Sudbury-area elk could be of concern and warrant further investigation.


Assuntos
Cervos/fisiologia , Metais Pesados/farmacocinética , Fatores Etários , Animais , Dieta , Exposição Ambiental , Fezes/química , Feminino , Indústrias , Rim/fisiologia , Fígado/fisiologia , Masculino , Metalurgia , Músculo Esquelético/fisiologia , Distribuição Tecidual
3.
Mol Ecol ; 9(10): 1561-76, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11050551

RESUMO

Eleven populations of wapiti (Cervus elaphus) were analysed for genetic diversity using 12 microsatellite loci. Samples were taken from Vancouver Island, British Columbia; Burwash and French River herds in Ontario; Ya Ha Tinda Ranch, Alberta; and Banff, Elk Island, Jasper, Kootenay, Riding Mountain, Yellowstone and Yoho National Parks. Overall, wapiti populations have on average three to four alleles per locus and an average expected heterozygosity that ranged from 25.75 to 52.85%. The greatest genetic distances were observed between the Vancouver population and all other populations. Using the assignment test, Roosevelt wapiti (C. e. roosevelti Merriam 1897) assigned only to the Vancouver Island population. The distance and assignment values suggest a divergence of the Roosevelt wapiti from other populations and support the subspecific status for the Vancouver Island population. No evidence was found for the existence of unique Eastern wapiti (C. e. canadensis Erxleben 1777) in the Burwash or French River herds in Ontario. The overlapping distribution of genotypes from indigenous populations from Riding Mountain, Elk Island and Yellowstone National Parks suggests that wapiti were once a continuous population before settlers decimated their numbers. The lack of differentiation between these populations raises questions about the status of Manitoban (C. e.manitobensis Millais 1915) and Rocky Mountain (C. e.nelsoni Bailey 1935) subspecies.


Assuntos
Cervos/genética , Genética Populacional , Repetições de Microssatélites , Animais , Impressões Digitais de DNA , América do Norte
4.
Calcif Tissue Int ; 41(1): 38-43, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3113700

RESUMO

Thyroxine (T4), triiodothyronine (T3), and alkaline phosphatase (AP) were assayed monthly in white-tailed deer plasma obtained from the antler (A), jugular (J), and the saphenous (S) veins during the period of antler growth and the period of mineralization. The concentrations of T3, T4, and AP in the J and S were not significantly different in any month. During the most intense antler growth period (June and July) AP levels were significantly higher and T3 significantly lower in A as compared to J and S, but no differences were found during the mineralization phase in August. T3 values from all three veins were significantly lower in the mineralization period than J and S values during the growing phase. Variations of T4 levels between A, J, and S as well as differences between months were only negligible. The data indicate that AP is produced in large quantity in the antler tissue during the growth period, but the amount is sharply reduced during the mineralization phase. T3 is utilized in the growing antler; the rate of utilization correlates with the intensity of antler growth. T4 is probably not utilized in the antler bone. Developing antler might be used as a model to study growth and mineralization processes of bony tissues.


Assuntos
Fosfatase Alcalina/sangue , Chifres de Veado/irrigação sanguínea , Cervos/fisiologia , Cornos/irrigação sanguínea , Veias Jugulares , Veia Safena , Tiroxina/sangue , Tri-Iodotironina/sangue , Animais , Chifres de Veado/crescimento & desenvolvimento , Masculino , Minerais/metabolismo , Estações do Ano , Veias
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