Date of Graduation

2018

Document Type

Dissertation

Degree Type

PhD

College

Davis College of Agriculture, Natural Resources and Design

Department

Division of Forestry and Natural Resources

Committee Chair

Amy B. Webb

Committee Member

James M. Crum

Committee Member

Stephen P. DiFazio

Committee Member

John E. Edwards

Committee Member

Michael P. Strager

Abstract

Although nearly extinct historically, the current population of white-tailed deer (Odocoileus virginianus) in West Virginia serves as a plentiful resource, however; currently there are two uncertainties to the socio-economic benefits of white-tailed deer in West Virginia: poaching and chronic wasting disease (CWD). While infection with the disease invariably results in a 100% fatality rate, previous studies have indicated that nucleotide polymorphisms in the 285th and 286th position of the prion precursor gene (PRNP) have been associated with the delay of clinical disease symptoms. To determine the association with CWD positive individuals in a CWDaffected population in West Virginia and determine temporal differences in polymorphism frequency before and after the first detection, 513 CWD negative female white-tailed deer were sampled in Hampshire County, WV as well as 146 CWD positive male and female white-tailed deer. Female white-tailed deer (CWD positive and negative) were also selected to determine any changes associated with PRNP polymorphisms and disease status as well as temporal changes before disease detection within a high density area of CWD detections (>1/km2 ).While polymorphisms at PRNP 285 (Adenine to Cytosine) were not statistically associated with disease detection at either sampling, polymorphisms at PRNP 286 (Guanine to Adenine) were statistically associated with the prevalence of disease detection at both samplings (P=0.000, P=0.0478). Comparisons between observed allele frequencies at PRNP 286 following CWD detection and expected allele frequencies found a significant decrease in frequency of the beneficial allele in both the high density sampling as well as the Hampshire County sampling. This result is counter to the expected increase in frequency if selection was occurring and may be due to migration. To determine the dispersal distance of 40 white-tailed deer (20 male, 20 females) testing positive for CWD, genotype profiles were generated using 16 microsatellite loci and the control region of the mitochondria (D-loop) for each individual was sequenced. Pairwise relatedness was calculated between 559 females and a focal individual testing positive for CWD and interpolated across the study region (Hampshire County). Although dispersal distances of females (14.6 km) were not statistically different from males (16.1 km; P=0.57), the dispersal pattern of females contrasted that of males. Females dispersed into a management area in which deer density was reduced through “special collections” whereas males dispersed through an area of high CWD density (>1 km2 ). Using the same microsatellite and mitochondrial control region, broad-scale genetic differentiation of white-tailed deer was detected across the 22 counties of West Virginia. Using the Bayesian genetic program STRUCTURE, a total of four genetic populations were determined to be the most likely. However, only 2% of genetic variation could be explained within the groups identified by STRUCTURE using an AMOVA. Additionally, after grouping haplotypes into mitochondrial clades, the majority of neighboring sampled counties had similar mitochondrial clade frequencies. Although a county by county genetic assignment could not be determined, the results of this study indicate that geographic assignment can be used to assign purportedly poached individuals to regions within West Virginia. However, exposure of evidence to environmental factors including changing temperatures and UV radiation may degrade evidence below qualities and quantities suitable for DNA analysis. Analysis through a one-way ANOVA indicated that both exposure to high temperatures and substrate significantly affected DNA quantity (P=0.000, P=0.0119, respectively); however exposure time had no influence on DNA quantity (P=0.444). Samples exposed to UV radiation were not significantly affected by exposure (P=0.785). Additionally, although substrate type did not significantly influence DNA quantity (P=0.258), an increase in exposure time significantly decreased DNA quantity (P = 0.018). Results from this study indicate that exposure to the environment can reduce the quantity of DNA; however, these quantities were large enough to be amplified through qPCR. Overall, the results of these studies provide a suite of management tools for assisting with the current problems facing a valuable resource in West Virginia.

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