Implications of Direct Contacts Between Mule Deer (odocoileus Hemionus) on Transmission of Chronic Wasting Disease

Implications of Direct Contacts Between Mule Deer (odocoileus Hemionus) on Transmission of Chronic Wasting Disease PDF Author: Maria Angelica Dobbin
Publisher:
ISBN:
Category : Chronic wasting disease
Languages : en
Pages : 0

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Book Description
Chronic wasting disease (CWD) is a fatal, prion disease of cervids that was first detected in Alberta in 2005. Transmission of CWD occurs by direct contact with an infected individual or via contaminated environments. I investigated the seasonal effects of landscape heterogeneity on direct, sex-specific (same or mixed sex) contacts of individuals within and between groups of mule deer (Odocoileus hemionus) in central eastern Alberta. Using data from collared deer, I determined group membership based on simultaneous movement, pair-wise relatedness from genetic sampling at capture, contact rates based on proximity loggers, and habitat characteristics of dyad (pairs) in space-use overlap based on GPS telemetry. I found that within-group contact rates were several orders of magnitude higher than between-group contacts, contact rates were unrelated to genetic relatedness, and within-group contacts rates were more dependent on the sex of individuals, between-group rates were more influences by habitat. I also determined where seasonal contacts were most likely to occur by comparing habitat characteristics of contact locations to random locations within areas of shared space use. In winter, contacts occurred in areas with higher use by deer, whereas in summer contact locations were less constrained and were more varied between sexes. The exceptions were that contacts were more likely to occur than expected by use in areas of limited woody cover in both winter and summer, less likely to occur in forest-open edges in winter, and closers to roads in summer. Predictions of where contacts occur among within and between-group male dyads in winter and between-group female dyads in summer were the best predictors of CWD risk derived from hunter-harvested infected deer detected during Alberta's CWD surveillance program. My results suggest that the pattern of CWD risk on the landscape is related to areas of deer contact, and that the seasonal, sex-specific contact rates may better inform transmission in spatially explicit models to help guide management strategies for an emergent wildlife disease.

Implications of Direct Contacts Between Mule Deer (odocoileus Hemionus) on Transmission of Chronic Wasting Disease

Implications of Direct Contacts Between Mule Deer (odocoileus Hemionus) on Transmission of Chronic Wasting Disease PDF Author: Maria Angelica Dobbin
Publisher:
ISBN:
Category : Chronic wasting disease
Languages : en
Pages : 0

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Book Description
Chronic wasting disease (CWD) is a fatal, prion disease of cervids that was first detected in Alberta in 2005. Transmission of CWD occurs by direct contact with an infected individual or via contaminated environments. I investigated the seasonal effects of landscape heterogeneity on direct, sex-specific (same or mixed sex) contacts of individuals within and between groups of mule deer (Odocoileus hemionus) in central eastern Alberta. Using data from collared deer, I determined group membership based on simultaneous movement, pair-wise relatedness from genetic sampling at capture, contact rates based on proximity loggers, and habitat characteristics of dyad (pairs) in space-use overlap based on GPS telemetry. I found that within-group contact rates were several orders of magnitude higher than between-group contacts, contact rates were unrelated to genetic relatedness, and within-group contacts rates were more dependent on the sex of individuals, between-group rates were more influences by habitat. I also determined where seasonal contacts were most likely to occur by comparing habitat characteristics of contact locations to random locations within areas of shared space use. In winter, contacts occurred in areas with higher use by deer, whereas in summer contact locations were less constrained and were more varied between sexes. The exceptions were that contacts were more likely to occur than expected by use in areas of limited woody cover in both winter and summer, less likely to occur in forest-open edges in winter, and closers to roads in summer. Predictions of where contacts occur among within and between-group male dyads in winter and between-group female dyads in summer were the best predictors of CWD risk derived from hunter-harvested infected deer detected during Alberta's CWD surveillance program. My results suggest that the pattern of CWD risk on the landscape is related to areas of deer contact, and that the seasonal, sex-specific contact rates may better inform transmission in spatially explicit models to help guide management strategies for an emergent wildlife disease.

Individual-based Movement Model of Mule Deer (Odocoileus Hemionus) Contacts and Application to Artificial Attractants

Individual-based Movement Model of Mule Deer (Odocoileus Hemionus) Contacts and Application to Artificial Attractants PDF Author: Kelsey M. Gritter
Publisher:
ISBN:
Category : Chronic wasting disease
Languages : en
Pages : 0

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Book Description
Chronic wasting disease (CWD) is an emerging prion disease in Canada that infects mule deer, white-tailed deer, elk, and moose by direct and environmental transmission and is invariably fatal. CWD spread can be promoted at "hotspots" that attract deer, such as attractants that are created in fields by hay bales and grain bags, and attractants such as grain bins and agricultural storage at farm sites. An individual-based model was created to investigate the effects of different densities and arrangements of hotspots on contact rates between- and within-groups. The model tracks contacts (when two individuals come within five meters of one another), which are defined as between- or within-group depending on the group membership of the two individuals. Simulations are run in Netlogo on a heterogeneous landscape and include behaviours such as grouping and home ranges. Using a two-hour time step, deer are moved across the landscape based on both step-selection movement rules relative to resources and group behaviours. The integrated step-selection function utilizes GIS layers for environmental weights and GPS-collar movement data for calculating step-selection coefficients, and step length distributions. Sensitivity analysis was performed on the model and revealed a greater sensitivity of within-group contacts to changes in model parameters, particularly group cohesion. Following model analysis, simulations were run to assess the effect of artificial attractant (AA) density and configuration using two strategies for initial placement of attractants, random and clustered around farms, and two strategies for removing them, random and by proximity to woody cover. Simulations revealed that reducing the number of attractants on the increases between-group contacts as well as unique contacts between deer. Additionally, reducing AA density generally increased overall unique visits per site indicating potentially greater environmental contamination at remaining sites. Although having no attractants produced the lowest contact rates, management must take into consideration the feasibility of eliminating all attractants and the potentially negative impacts if sufficient reduction of AAs is not achieved. Additionally, the strategy used to eliminate attractants must be considered because although removal by proximity to woody cover and random removal showed similar patterns, removing by proximity to woody cover caused a greater increase in contacts for field attractants. For removal at clusters around farms, removing individual attractants versus all attractants in a cluster resulted in different trends as removing individually had a limited effect on contacts, whereas removing by cluster caused an increase in between-group contacts. If feasible, management should aim to eliminate attractants via mitigation strategies and enforcement; however, if insufficient resources are available for enforcement, then management strategies should be taken with caution because insufficient reduction of attractants could worsen contact rates.

Mule and Black-tailed Deer of North America

Mule and Black-tailed Deer of North America PDF Author: Olof C. Wallmo
Publisher:
ISBN:
Category : Nature
Languages : en
Pages : 632

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Book Description
Developed in co-operation with U.S. Department of Agriculture, Forest Service.

How the Cows Turned Mad

How the Cows Turned Mad PDF Author: Maxime Schwartz
Publisher: Univ of California Press
ISBN: 0520243374
Category : Medical
Languages : en
Pages : 264

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Book Description
"How the Cows Turned Mad tells the story of a disease that continues to elude on many levels. Yet science has come far in understanding its origins, incubation, and transmission. This book is a case history that illuminates the remarkable progression of science."--BOOK JACKET.

Slow Transmissible Diseases of the Nervous System: Clinical, epidemiological, genetic, and pathological aspects of the spongiform encephalopathies

Slow Transmissible Diseases of the Nervous System: Clinical, epidemiological, genetic, and pathological aspects of the spongiform encephalopathies PDF Author: Stanley B. Prusiner
Publisher:
ISBN:
Category : Medical
Languages : en
Pages : 504

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Factors Affecting Movement Patterns of Mule Deer ('Odocoileus Hemionus') in Southern Saskatchewan

Factors Affecting Movement Patterns of Mule Deer ('Odocoileus Hemionus') in Southern Saskatchewan PDF Author: Erin Rae Silbernagel
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Factors Affecting Movement Patterns of Mule Deer ([i]Odocoileus Hemionus[/i] in Southern Saskatchewan

Factors Affecting Movement Patterns of Mule Deer ([i]Odocoileus Hemionus[/i] in Southern Saskatchewan PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Chronic Wasting Disease of Mule Deer

Chronic Wasting Disease of Mule Deer PDF Author: Christina Jenny Sigurdson
Publisher:
ISBN:
Category : Mule deer
Languages : en
Pages : 194

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Investigation and Management of Disease in Wild Animals

Investigation and Management of Disease in Wild Animals PDF Author: G.A. Wobeser
Publisher: Springer Science & Business Media
ISBN: 1475756097
Category : Science
Languages : en
Pages : 257

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Book Description
- A hypothesis is a proposition, set forth as an explanation for the occurrence of a phenomenon, that can be tested. - The basis for scientific investigation is the collection of information to formulate and test hypotheses. - Experimental methods measure the effect of manipulations caused by the investigator; observational methods collect information about naturally occurring events. - There are three sub-types of experimental techniques that differ in the way subjects are chosen for inclusion in the study, in the amount of control that the investigator has over variables, and in the method used to assess changes in other variables. - Descriptive observational studies dominate the early phase of most investigations and involve the description of disease-related events in the population. Associations among factors may be observed but the strength of the associations is not measured. - Analytical observation al techniques are of three basic types: prevalence surveys, case:control studies, and incidence or cohort studies. All attempt to explain the nature of relationships among various factors and to measure the strength of associations. - Prevalence surveys and case:control studies deal with disease existing at the time of the study; incidence studies are concerned with the development of disease over time. - Observational studies may be retrospective, using existing data, or prospective with collection of new information.

Landscape Ecology of Mule Deer (Odocoileus Hemionus) and White-tailed Deer (o. Virginianus) with Implications for Chronic Wasting Disease

Landscape Ecology of Mule Deer (Odocoileus Hemionus) and White-tailed Deer (o. Virginianus) with Implications for Chronic Wasting Disease PDF Author: Barry Richard Nobert
Publisher:
ISBN:
Category : Chronic wasting disease
Languages : en
Pages :

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