Hunter-harvested White-tailed Deer Research Articles

Direct Evidence of Powassan Virus Vertical Transmission in Ixodes scapularis in Nature.

Powassan virus (POWV) is a tick-borne flavivirus endemic in North America and Russia. Experimental infections with POWV have confirmed horizontal, transstadial, vertical, and cofeeding transmission routes for potential virus maintenance. In the field, vertical transmission has never been observed. During New York State tick-borne pathogen surveillance, POWV RNA and/or infectious POWV was detected in five pools of questing Ixodes scapularis larvae. Additionally, engorged female I. scapularis adults were collected from hunter-harvested white-tailed deer (Odocoileus virginianus) in a region with relatively high tick infection rates of POWV and allowed to oviposit under laboratory conditions. POWV RNA was detected in three female adult husks and one pool of larvae from a positive female. Infectious virus was isolated from all three RNA-positive females and the single positive larval pool. The detection of RNA and infectious virus in unfed questing larvae from the field and larvae from replete females collected from the primary tick host implicates vertical transmission as a potential mechanism for the maintenance of POWV in I. scapularis in nature, and elucidates the potential epidemiological significance of larval ticks in the transmission of POWV to humans.

DETECTION OF SARS-COV-2 NEUTRALIZING ANTIBODIES IN RETROPHARYNGEAL LYMPH NODE EXUDATES OF WHITE-TAILED DEER (ODOCOILEUS VIRGINIANUS) FROM NEBRASKA, USA.

Disease surveillance testing for emerging zoonotic pathogens in wildlife is a key component in understanding the epidemiology of these agents and potential risk to human populations. Recent emergence of SARS-CoV-2 in humans, and subsequent detection of this virus in wildlife, highlights the need for developing new One Health surveillance strategies. We used lymph node exudate, a sample type that is routinely collected in hunter-harvested white-tailed deer (WTD, Odocoileus virginianus) for surveillance of chronic wasting disease, to assess anti-SARS-CoV-2 neutralizing antibodies. A total of 132 pairs of retropharyngeal lymph nodes collected from Nebraska WTD harvested in Nebraska, US, in 2019 (pre-SARS-CoV-2 pandemic) and 2021 (post-SARS-CoV-2 pandemic) were tested for SARS-CoV-2 with reverse transcription PCR. Thereafter, exudates obtained from these same lymph nodes were tested for SARS-CoV-2 neutralizing antibodies using a surrogate virus neutralization test. Neutralizing antibodies were detected in the exudates with high diagnostic specificity (100% at proposed cutoff of 40% inhibition). Application of this testing approach to samples collected for use in other disease surveillance activities may provide additional epidemiological data on SARS-CoV-2 exposure, and there is further potential to apply this sample type to detection of other pathogens of interest.

Spatial epidemiology of hemorrhagic disease in Illinois wild white-tailed deer

Epizootic hemorrhagic disease (EHD) and bluetongue (BT) are vector-borne viral diseases that affect wild and domestic ruminants. Clinical signs of EHD and BT are similar; thus, the syndrome is referred to as hemorrhagic disease (HD). Syndromic surveillance and virus detection in North America reveal a northern expansion of HD. High mortalities at northern latitudes suggest recent incursions of HD viruses into northern geographic areas. We evaluated the occurrence of HD in wild Illinois white-tailed deer from 1982 to 2019. Our retrospective space–time analysis identified high-rate clusters of HD cases from 2006 to 2019. The pattern of northward expansion indicates changes in virus-host-vector interactions. Serological evidence from harvested deer revealed prior infection with BTV. However, BTV was not detected from virus isolation in dead deer sampled during outbreaks. Our findings suggest the value of capturing the precise geographic location of outbreaks, the importance of virus isolation to confirm the cause of an outbreak, and the importance of expanding HD surveillance to hunter-harvested wild white-tailed deer. Similarly, it assists in predicting future outbreaks, allowing for targeted disease and vector surveillance, helping wildlife agencies communicate with the public the cause of mortality events and viral hemorrhagic disease outcomes at local and regional scales.

Patterns of deer ked (Diptera: Hippoboscidae) and tick (Ixodida: Ixodidae) infestation on white-tailed deer (Odocoileus virginianus) in the eastern United States

BackgroundWhite-tailed deer (Odocoileus virginianus) host numerous ectoparasitic species in the eastern USA, most notably various species of ticks and two species of deer keds. Several pathogens transmitted by ticks to humans and other animal hosts have also been found in deer keds. Little is known about the acquisition and potential for transmission of these pathogens by deer keds; however, tick-deer ked co-feeding transmission is one possible scenario. On-host localization of ticks and deer keds on white-tailed deer was evaluated across several geographical regions of the eastern US to define tick-deer ked spatial relationships on host deer, which may impact the vector-borne disease ecology of these ectoparasites.MethodsTicks and deer keds were collected from hunter-harvested white-tailed deer from six states in the eastern US. Each deer was divided into three body sections, and each section was checked for 4 person-minutes. Differences in ectoparasite counts across body sections and/or states were evaluated using a Bayesian generalized mixed model.ResultsA total of 168 white-tailed deer were inspected for ticks and deer keds across the study sites. Ticks (n = 1636) were collected from all surveyed states, with Ixodes scapularis (n = 1427) being the predominant species. Counts of I. scapularis from the head and front sections were greater than from the rear section. Neotropical deer keds (Lipoptena mazamae) from Alabama and Tennessee (n = 247) were more often found on the rear body section. European deer keds from Pennsylvania (all Lipoptena cervi, n = 314) were found on all body sections of deer.ConclusionsThe distributions of ticks and deer keds on white-tailed deer were significantly different from each other, providing the first evidence of possible on-host niche partitioning of ticks and two geographically distinct deer ked species (L. cervi in the northeast and L. mazamae in the southeast). These differences in spatial distributions may have implications for acquisition and/or transmission of vector-borne pathogens and therefore warrant further study over a wider geographic range and longer time frame.Graphical

Serologic Survey of Mosquito-Borne Viruses in Hunter-Harvested White-Tailed Deer (Odocoileus virginianus), New York State.

Sera from white-tailed deer (WTD, Odocoileus virginianus) hunter-harvested throughout New York State (NYS), 2007-2015, were tested by plaque reduction neutralization for antibodies against nine mosquito-borne viruses from the families Peribunyaviridae, Flaviviridae, and Togaviridae. Overall, 76.1% (373/490) of sampled WTD were seropositive against at least one virus, and 38.8% were exposed to multiple viruses. The seropositivity rate in adult WTD (78.0%) was significantly greater (P < 0.0001) than that in fawns (47.7%). Neutralizing antibodies against California serogroup viruses were most common in WTD sampled across all regions (67.1%), followed by the Bunyamwera serogroup (BUN) (37.6%). Jamestown Canyon and Cache Valley orthobunyaviruses were responsible for most California and BUN infections, respectively. Seroprevalence rates to West Nile virus were higher in samples originating from Long Island (LI) (19.0%) than in those originating from the central (7.3%), western (5.0%), and Hudson Valley (4.4%) regions of NYS. Antibodies to Eastern equine encephalitis virus were seen primarily in WTD from central NYS (5.1%), where annual enzootic activity occurs, but low rates were documented in western NYS (1.4%) and LI (1.7%). Low rates of Potosi and LaCrosse orthobunyavirus, and Highlands J virus antibodies were detected over the course of this investigation. St. Louis encephalitis virus (or a closely related virus) antibodies were detected in samples collected from central and western NYS, suggesting local virus transmission despite a lack of evidence from routine mosquito surveillance. Serologic results demonstrate the value of WTD in NYS as an indicator of arbovirus distribution and recent transmission on a relatively fine spatial scale.

Age structuring and spatial heterogeneity in prion protein gene (PRNP) polymorphism in white-tailed deer

ABSTRACT Chronic-wasting disease (CWD) is a prion-derived fatal neurodegenerative disease that has affected wild cervid populations on a global scale. Susceptibility has been linked unambiguously to several amino acid variants within the prion protein gene (PRNP). Quantifying their distribution across landscapes can provide critical information for agencies attempting to adaptively manage CWD. Here we attempt to further define management implications of PRNP polymorphism by quantifying the contemporary geographic distribution (i.e., phylogeography) of PRNP variants in hunter-harvested white-tailed deer (WTD; Odocoileus virginianus, N = 1433) distributed across Arkansas (USA), including a focal spot for CWD since detection of the disease in February 2016. Of these, PRNP variants associated with the well-characterized 96S non-synonymous substitution showed a significant increase in relative frequency among older CWD-positive cohorts. We interpreted this pattern as reflective of a longer life expectancy for 96S genotypes in a CWD-endemic region, suggesting either decreased probabilities of infection or reduced disease progression. Other variants showing statistical signatures of potential increased susceptibility, however, seemingly reflect an artefact of population structure. We also showed marked heterogeneity across the landscape in the prevalence of ‘reduced susceptibility’ genotypes. This may indicate, in turn, that differences in disease susceptibility among WTD in Arkansas are an innate, population-level characteristic that is detectable through phylogeographic analysis.

Vertical transmission rates of Borrelia miyamotoi in Ixodes scapularis collected from white-tailed deer

Borrelia miyamotoi is a relapsing fever spirochete transmitted by ticks in the Ixodes ricinus complex. In the eastern United States, B. miyamotoi is transmitted by I. scapularis, which also vectors several other pathogens including B. burgdorferi sensu stricto. In contrast to Lyme borreliae, B. miyamotoi can be transmitted vertically from infected female ticks to their progeny. Therefore, in addition to nymphs and adults, larvae can vector B. miyamotoi to wildlife and human hosts. Two widely varying filial infection prevalence (FIP) estimates - 6% and 73% - have been reported previously from two vertically infected larval clutches; to our knowledge, no other estimates of FIP or transovarial transmission (TOT) rates for B. miyamotoi have been described in the literature. Thus, we investigated TOT and FIP of larval clutches derived from engorged females collected from hunter-harvested white-tailed deer in 2015 (n = 664) and 2016 (n = 599) from Maine, New Hampshire, Tennessee, and Wisconsin. After engorged females oviposited in the lab, they (n = 492) were tested for B. miyamotoi infection by PCR. Subsequently, from each clutch produced by an infected female, larval pools, as well as 100 individual eggs or larvae, were tested. The TOT rate of the 11 infected females was 90.9% (95% CI; 57.1–99.5%) and the mean FIP of the resulting larval clutches was 84.4% (95% CI; 68.1–100%). Even though the overall observed vertical transmission rate (the product of TOT and FIP; 76.7%, 95% CI; 44.6–93.3%) was high, additional horizontal transmission may be required for enzootic maintenance of B. miyamotoi based on the results of a previously published deterministic model. Further investigation of TOT and FIP variability and the underlying mechanisms, both in nature and the laboratory, will be needed to resolve this question. Meanwhile, studies quantifying the acarological risk of Borrelia miyamotoi disease need to consider not only nymphs and adults, but larval I. scapularis as well.

Borrelia miyamotoi infection rate in black-legged ticks (Ixodes scapularis) recovered from heads of hunter-harvested white-tailed deer (Odocoileus virginianus) in Pennsylvania: A public health perspective

Abstract Studies reporting tick infection rates for Borrelia miyamotoi, a zoonotic arthropod-borne pathogen responsible for Borrelia miyamotoi disease, in the Commonwealth of Pennsylvania are limited. To ascertain a statewide infection rate of B. miyamotoi, ticks were collected from heads of 9,912 hunter-harvested white-tailed deer (Odocoileus virginianus) presented to six regional Pennsylvania Game Commission Chronic Wasting Disease sampling stations in early December of 2013, 2014, and 2015. Of the 2973 ticks recovered, 1990 (66.9%) were identified as adult Ixodes scapularis. The 1990 I. scapularis ticks were grouped into 409 pools containing one to six ticks and PCR-tested for the presence of B. miyamotoi. The pooled samples had a statewide maximum likelihood estimation tick infection rate of 7.64/1000 (95% CI, 4.46–12.29) for B. miyamotoi, confirming a state-wide presence, and supporting the need for an increased public health awareness for this emerging zoonotic arthropod-borne pathogen.

Range Expansion of Fascioloides magna in North Carolina

In North Carolina, Odocoileus virginianus (White-tailed Deer) are the definitive natural hosts of Fascioloides magna (Giant Liver Fluke). Previous research identified the enzootic range of Giant Liver Fluke in North Carolina to be within the Tar River and Roanoke River Basins in Halifax and neighboring counties. Recent Giant Liver Fluke infections of Ovis aries (Domestic Sheep), Capra hircus (Domestic Goat), Lama glama (Llama), Vicugna pacos (Alpaca), and Bos taurus (Cattle) outside the historic enzootic range prompted us to investigate the current range of Giant Liver Fluke in North Carolina. From September 2014 to January 2015, we examined livers from hunter-harvested White-tailed Deer within 16 North Carolina counties. We detected Giant Liver Fluke in livers from 5 counties, with an overall prevalence of 10.3%. Besides reporting the first Giant Liver Fluke infections of livestock in North Carolina, we documented new geographic localities (Cabarrus, Franklin, Mecklenburg, Union, Wake, and Washington counties) for Giant Liver Fluke. An increased impact on North Carolina livestock is likely with the possible range expansion of Giant Liver Fluke, which may be related to the increase in populations of White-tailed Deer.

Evidence of Powassan/deer tick virus in adult black-legged ticks (Ixodes scapularis) recovered from hunter-harvested white-tailed deer (Odocoileus virginianus) in Pennsylvania: A public health perspective.

Studies reporting tick infection rates for Powassan virus (POWV), an emerging zoonotic arthropod-borne pathogen responsible for POWV disease in the Commonwealth of Pennsylvania, are limited. To determine the presence and ascertain a statewide prevalence of POWV, ticks were collected from 9,912 hunter-harvested white-tailed deer (Odocoileus virginianus) heads presented to six regional Pennsylvania Game Commission Chronic Wasting Disease sampling stations in early December of 2013, 2014 and 2015. Of the 2,973 ticks recovered, 1,990 (66.9%) were identified as adult Ixodes scapularis (black-legged tick). The 1,990 I.scapularis ticks were PCR-tested for the presence of POWV. The ticks had a statewide Powassan/deer tick virus infection rate of 0.05%, providing evidence of this pathogen in Pennsylvania's adult I.scapularis ticks and supporting the need for more comprehensive pathogen prevalence assessment strategies, as well as increased public health awareness for this emerging zoonotic arthropod-borne pathogen of public health concern.

Ticks collected in late fall from hunter-harvested white-tailed deer (Odocoileus virginianus) heads in Pennsylvania, 2013–2015

Abstract Despite studies indicating the presence of Dermacentor albipictus (Acari: Ixodidae) in Pennsylvania, no published studies confirm the prominence of the tick throughout the state. During the fall of 2013, 2014, and 2015, 9912 hunter-harvested white-tailed deer (Odocoileus virginianus) heads were presented at six chronic wasting disease sampling stations across Pennsylvania, where tick collection took place. A total of 2973 ticks, representing I. scapularis (n = 1990, 66.9%) and D. albipictus (n = 983, 33.1%), were recovered, reaffirming I. scapularis as the more prevalent tick in Pennsylvania and confirming the prominence of D. albipictus throughout the state.

Evaluation of pathogen-specific biomarkers for the diagnosis of tuberculosis in white-tailed deer (Odocoileus virginianus)

OBJECTIVE To develop a noninvasive biomarker-based detection system specific for Mycobacterium bovis for monitoring infection in wild animals. SAMPLE Serum samples from 8 experimentally infected yearling white-tailed deer (Odocoileus virginianus) and 3 age-matched control deer and from 393 Minnesota Department of Natural Resources hunter-harvested white-tailed deer in northwest Minnesota. PROCEDURES 8 yearling deer were inoculated with 2 × 108 CFUs of virulent M bovis strain 1315 (day 0), and sera were obtained on days 0, 19, 48, and 60; sera were obtained from 3 uninoculated control deer on those same days. Sera from these deer and 9 M bovis-positive hunter-harvested deer were tested for 3 Mycobacterium-specific biomarkers (MB1895c, MB2515c, and polyketide synthase 5) by use of an indirect ELISA. That same ELISA was used to test sera obtained from 384 exposed noninfected deer in northwest Minnesota from 2007 through 2010, concurrent with an outbreak of tuberculosis involving cattle and deer in that region. RESULTS ELISA results revealed that tuberculosis infection could be detected as early as 48 days after inoculation in experimentally infected deer. Results for 384 deer sera revealed that prevalence of tuberculosis decreased over the 4-year period. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that the prevalence of tuberculosis in Minnesota deer decreased after 2009 but tuberculosis may have persisted (as subclinical disease) at extremely low levels, as indicated by the presence of low concentrations of circulating biomarkers. Biomarker-based diagnostic tests may offer a specific approach for early identification of M bovis infection.

Bacterial Fauna of the Forehead, Tongue, and Nasal Mucosa ofOdocoileus virginianus(White-Tailed Deer) in Georgia

Abstract Identification of the bacterial fauna associated with the skin, nasal mucosa, and tongue of Odocoileus virginianus (White-tailed Deer) may provide some insight into deer health and potential risks for humans from contact with deer. Few bacterial surveys have investigated White-tailed Deer, despite the commonality of human—deer interactions. From October to December 2011, we collected swab samples from the forehead, nose, and tongue of 39 hunter-harvested White-tailed Deer in Georgia. We inoculated and incubated agar plates for 48 h at 35 °C and identified the isolated bacterial colonies to genus using the bioMerieux Vitek 2 system. We amplified and sequenced portions of the 16s ribosomal-RNA gene, and used the products to identify 60 species of bacteria, including 342 Gram-positive isolates and 93 Gram-negative isolates. Although most species isolated from White-tailed Deer were nonpathogenic environmental bacteria, good hygiene is recommended when handling these animals.

Prevalence of five tick-borne bacterial genera in adult Ixodes scapularis removed from white-tailed deer in western Tennessee.

BackgroundIn the northeastern and midwestern regions of the United States Ixodes scapularis Say transmits the causal agents of anaplasmosis (Anaplasma phagocytophilum), babesiosis (Babesia microti), and borreliosis (Borrelia burgdorferi and B. miyamotoi). In the southeastern United States, none of those pathogens are considered endemic and two other tick-borne diseases (TBDs) (ehrlicihosis and rickettiosis) are more common. Our objective was to determine baseline presence and absence data for three non-endemic bacterial agents (Anaplasma, Borrelia and Babesia) and two commonly reported bacterial agents (Ehrlichia, and Rickettsia) in southern I. scapularis (n = 47) collected from 15 hunter-harvested white-tailed deer (Odocoileus virginianus) in western Tennessee.FindingsOf the 47 ticks, 27 tested PCR positive for non-pathogenic Rickettsia species, two for Ehrlichia ewingii, one for Ehrlichia sp. “Panola Mountain”, and one for Anaplasma phagocytophilum variant 1 strain. None of these ticks were positive for Babesia or Borrelia (including B. burgdorferi).ConclusionsFinding human pathogens in host-fed I. scapularis merits additional studies surveying pathogen prevalence in questing ticks. Collection of questing I. scapularis in their peak activity months should be undertaken to determine the overall encounter rates and relative risk of pathogenic Ehrlichia in southern I. scapularis. Ehrlichia sequences were homologous to previous human isolates, but neither Babesia nor B. burgdorferi were identified in these ticks. With the identification of pathogenic bacteria in this relatively small collection of I. scapularis from western Tennessee, the study of the absence of Lyme disease in the south should be refocused to evaluate the role of pathogenic Ehrlichia in southern I. scapularis.

Prevalence of five tick-borne bacterial genera in adult Ixodes scapularis removed from white-tailed deer in western Tennessee

In the northeastern and midwestern regions of the United States Ixodes scapularis Say transmits the causal agents of anaplasmosis (Anaplasma phagocytophilum), babesiosis (Babesia microti), and borreliosis (Borrelia burgdorferi and B. miyamotoi). In the southeastern United States, none of those pathogens are considered endemic and two other tick-borne diseases (TBDs) (ehrlicihosis and rickettiosis) are more common. Our objective was to determine baseline presence and absence data for three non-endemic bacterial agents (Anaplasma, Borrelia and Babesia) and two commonly reported bacterial agents (Ehrlichia, and Rickettsia) in southern I. scapularis (n = 47) collected from 15 hunter-harvested white-tailed deer (Odocoileus virginianus) in western Tennessee. Of the 47 ticks, 27 tested PCR positive for non-pathogenic Rickettsia species, two for Ehrlichia ewingii, one for Ehrlichia sp. “Panola Mountain”, and one for Anaplasma phagocytophilum variant 1 strain. None of these ticks were positive for Babesia or Borrelia (including B. burgdorferi). Finding human pathogens in host-fed I. scapularis merits additional studies surveying pathogen prevalence in questing ticks. Collection of questing I. scapularis in their peak activity months should be undertaken to determine the overall encounter rates and relative risk of pathogenic Ehrlichia in southern I. scapularis. Ehrlichia sequences were homologous to previous human isolates, but neither Babesia nor B. burgdorferi were identified in these ticks. With the identification of pathogenic bacteria in this relatively small collection of I. scapularis from western Tennessee, the study of the absence of Lyme disease in the south should be refocused to evaluate the role of pathogenic Ehrlichia in southern I. scapularis.

Spatial point pattern analyses of Bovine viral diarrhea virus infection in domestic livestock herds and concomitant seroprevalence in wild white-tailed deer (Odocoileus virginianus) in New York State, USA

Bovine viral diarrhea virus (BVDV) is an economically important disease of domestic cattle that is capable of infecting cervids. A first step in the formulation of a regional BVDV management plan is a local assessment of the likelihood of pathogen transmission from wildlife to domestic livestock. To achieve this, blood samples were collected from hunter-harvested white-tailed deer (Odocoileus virginianus) throughout New York State in the fall of 2009 and 2010. The SVANOVIR BVDV p80-AB enzyme-linked immunosorbent assay (ELISA; Svanova Biotech AV, Uppsala, Sweden) was used to screen sera for anti-BVDV antibodies. Because this ELISA is not validated for use in white-tailed deer, sera that tested positive were tested again using serum neutralization to verify the presence of antibodies. Spatial data describing the geographic location of BVDV antigen-positive cattle and camelid herds and BVDV-seropositive white-tailed deer were analyzed via the dual kernel density estimation method. In white-tailed deer, 7.48% (80/1,069) were BVDV-seropositive, whereas 3.43% (144/4,195) of tested herds were positive for BVDV antigen. An exploratory cluster analysis revealed 1 significant cluster of BVDV antigen-positive herds and 2 significant clusters of BVDV-seropositive deer. There was no spatial overlap between the clusters. The spatial point pattern and exploratory cluster analyses suggest that BVDV is maintained independently in domestic livestock herds in the western part of the state and in the white-tailed deer population in the northwestern part of the state.

&lt;I&gt;Borrelia burgdorferi&lt;/I&gt; Not Detected in Widespread &lt;I&gt;Ixodes scapularis&lt;/I&gt; (Acari: Ixodidae) Collected From White-Tailed Deer in Tennessee

Lyme disease (LD), caused by the bacterium Borrelia burgdorferi and transmitted in the eastern United States by blacklegged ticks, Ixodes scapularis Say, is classified as nonendemic in Tennessee and surrounding states in the Southeast. Low incidence of LD in these states has been attributed, in part, to vector ticks being scarce or absent; however, tick survey data for many counties are incomplete or out of date. To improve our knowledge of the distribution, abundance, and Borrelia spp. prevalence of I. scapularis, we collected ticks from 1,018 hunter-harvested white-tailed deer (Odocoileus virginianus (Zimmerman)) from 71 of 95 Tennessee counties in fall 2007 and 2008. In total, 160 deer (15.7%) from 35 counties were infested with adult I. scapularis; 30 of these counties were new distributional records for this tick. The mean number of I. scapularis collected per infested deer was 5.4 +/- 0.6 SE. Of the 883 I. scapularis we removed from deer, none were positive for B. burgdorferi and one tested positive for B. miyamotoi. Deer are not reservoir hosts for B. burgdorferi; nevertheless, past surveys in northern LD-endemic states have readily detected B. burgdoreferi in ticks collected from deer. We conclude that I. scapularis is far more widespread in Tennessee than previously reported. The absence of detectable B. burgdorferi infection among these ticks suggests that the LD risk posed by I. scapularis in the surveyed areas of Tennessee is much lower than in LD-endemic areas of the Northeast and upper Midwest.

The occurrence of Bovine viral diarrhea virus in hunter-harvested white-tailed deer (Odocoileus virginianus) in the state of Georgia, southeastern United States

The prevalence of Bovine viral diarrhea virus (BVDV) in free-ranging white-tailed deer (WTD, Odocoileus virginianus) in the state of Georgia was evaluated using ear notches collected from hunter-harvested deer during the hunting season of 2010-2011. From September to December 2010, 367 ear samples from WTD were collected from 37 counties in Georgia. The samples were from 178 (48.5%) female deer, 187 (51%) male deer, and 2 (0.5%) of unknown sex. The age of the animals varied from 6 months to 6.5 years. The age was not recorded in 34 animals (9.3%). Of the animals with known ages, 42% were under 2 years. Screening of 367 samples for BVDV using an antigen-capture enzyme-linked immunosorbent assay (AgELISA) resulted in 364 negative samples and 3 suspect samples. The 3 suspect samples were negative for BVDV reverse transcription polymerase chain reaction (RT-PCR), virus isolation, and immunohistochemistry. A subpopulation of samples (n = 89) selected from various geographical regions also tested negative for BVDV RT-PCR. In conclusion, although a few of the samples were suspect for the presence of BVDV by AgELISA, the presence of the virus within the deer population studied could not be confirmed further.

Evaluation of the Tooth-wear and Replacement Method for Aging White-tailed Deer (Odocoileus virginianus) on the Blue Grass Army Depot, Madison County, Kentucky

ABSTRACT We evaluated the reliability of the tooth-wear and replacement method for aging hunter-harvested deer on the Blue Grass Army Depot, Madison County, Kentucky. Eighty-seven hunter-harvested white-tailed deer were aged using the tooth-wear and replacement procedure and had an incisor tooth removed for aging via the cementum annuli method. We found no significant difference (P < 0.05) in the distribution of ages (1.5 years, 2.5 years, 3.5 years, ≥4.5 years) assigned using either method for male (X2 = 6.69) or female (X2 = 6.85) deer. The majority (77%) of the tooth-wear: cementum pairs of age estimates were in agreement for deer in this study. The tooth-wear and replacement technique tended to identify the age of female white-tailed deer ≥3.5 years of age incorrectly.

Evaluation of horizontal transmission of bovine viral diarrhea virus type 1a from experimentally infected white-tailed deer fawns (Odocoileus virginianus) to colostrum-deprived calves

To assess the transmission of bovine viral diarrhea virus (BVDV) from experimentally infected white-tailed deer fawns to colostrum-deprived calves by use of a BVDV strain isolated from hunter-harvested white-tailed deer. 5 white-tailed deer (Odocoileus virginianus) fawns and 6 colostrum-deprived calves. Fawns were inoculated intranasally with a noncytopathic BVDV-1a isolate (2 mL containing 10(6.7) TCID(50)/mL), and 2 days after inoculation, animals were commingled until the end of the study. Blood and serum samples were obtained on days -6, 0, 7, 14, and 21 after inoculation for reverse transcriptase PCR assay, virus neutralization, and BVDV-specific antibody ELISA. Nasal, oral, and rectal swab specimens were collected on days 0, 3, 7, 14, 17, and 21 for reverse transcriptase PCR testing. By 21 days after inoculation, all animals were euthanized and necropsied and tissues were collected for histologic evaluation, immunohistochemical analysis, and virus isolation. All fawns became infected and shed the virus for up to 18 days as determined on the basis of reverse transcriptase PCR testing and virus isolation results. Evidence of BVDV infection as a result of cohabitation with acutely infected fawns was detected in 4 of the 6 calves by means of reverse transcriptase PCR testing and virus isolation. On the basis of these findings, BVDV transmission from acutely infected fawns to colostrum-deprived calves appeared possible.