Feral Swine Populations Research Articles

Molecular population structure for feral swine in the United States

ABSTRACTFeral swine (Sus scrofa) have invaded most of the United States and continue to expand throughout North America. Given the ecological and economic threats posed by increasing feral swine abundance, it is imperative to develop an understanding of their patterns of natural range expansion and human‐mediated introductions. Towards this goal, we used molecular markers to elucidate the genetic structure of feral swine populations throughout the United States and evaluated the association between historical introductions and contemporary patterns of genetic organization. We used STRUCTURE and discriminant analysis of principal components (DAPC) to delineate genetic clusters for 959 individuals genotyped at 88 single nucleotide polymorphism loci. We identified 10 and 12 genetic clusters for the 2 clustering approaches, respectively. We observed strong agreement in clusters across approaches, with both describing clusters having strong geographic association at regional levels reflecting past introduction and range expansion patterns. In addition, we evaluated patterns of isolation by distance to test for and estimate spatial scaling of population structure within western, central, and eastern regions of North America. We found contrasting spatial patterns of genetic relatedness among regions, suggesting differences in the invasion process, likely as a result of regional variation in landscape heterogeneity and the influence of human‐mediated introductions. Our results indicate that molecular analyses of population genetic structure can provide reliable insights into the invasion processes of feral swine, thus providing a useful basis for management focused on minimizing continued range expansion by this problematic species. © 2018 The Wildlife Society.

A Review of Classical Swine Fever Virus and Routes of Introduction into the United States and the Potential for Virus Establishment.

Classical swine fever (CSF) is caused by CSF virus (CSFV) which can be the source of substantial morbidity and mortality events in affected swine. The disease can take one of several forms (acute, chronic, or prenatal) and depending on the virulence of the inoculating strain may result in a lethal infection irrespective of the form acquired. Because of the disease-free status of the United States and the high cost of a viral incursion, a summary of US vulnerabilities for viral introduction and persistence is provided. The legal importation of live animals as well as animal products, byproducts, and animal feed serve as a potential route of viral introduction. Current import regulations are described as are mitigation strategies that are commonly utilized to prevent pathogens, including CSFV, from entering the US. The illegal movement of suids and their products as well as an event of bioterrorism are both feasible routes of viral introduction but are difficult to restrict or regulate. Ultimately, recommendations are made for data that would be useful in the event of a viral incursion. Population and density mapping for feral swine across the United States would be valuable in the event of a viral introduction or spillover; density data could further contribute to understanding the risk of infection in domestic swine. Additionally, ecological and behavioral studies, including those that evaluate the effects of anthropogenic food sources that support feral swine densities far above the carrying capacity would provide invaluable insight to our understanding of how human interventions affect feral swine populations. Further analyses to determine the sampling strategies necessary to detect low levels of antibody prevalence in feral swine would also be valuable.

Zoonotic pathogens from feral swine that pose a significant threat to public health.

The natural fecundity of suids, great ability to adapt to new habitats and desire for local hunting opportunities leading to translocation of feral pigs to regions where they are not yet established have all been instrumental in the home range expansion of feral swine. Feral swine populations in the United States continue to expand, wreaking havoc on agricultural lands, further compromising threatened and endangered species, and posing a microbiological threat to humans, domestic livestock and companion animals. This manuscript thoroughly reviews zoonotic diseases of concern including brucellosis, bovine tuberculosis, leptospirosis, enteric pathogens, both Salmonella spp. and shiga toxin-producing Escherichia coli, and hepatitis E. These pathogens are not a comprehensive list of microbes that are capable of infecting both humans and feral swine, but rather have been selected as they are known to infect US feral swine, direct transmission between wild suids and humans has previously been documented, or they have been shown to be readily transmitted during processing or consumption of feral swine pork. Humans that interact directly or indirectly with feral swine are at much higher risk for the development of a number of zoonotic pathogens. Numerous case reports document transmission events from feral swine and wild boar to humans, and the resulting diseases may be mild and self-limiting, chronic or fatal. Individuals that interact with feral swine should take preventative measures to minimize the risk of disease transmission and all meat should be thoroughly cooked. Additionally, public health campaigns to increase knowledge of the risks associated with feral swine are imperative.

Efficiency of different spatial and temporal strategies for reducing vertebrate pest populations

Understanding effectiveness of control strategies of pest species is fundamental for planning efficient and cost-effective management programs. In addition to culling rates, there are many potential factors that can determine efficiency of different management strategies, including demographic processes such as immigration rates, birth dynamics, and spatial ecology. We developed a stochastic, data-based simulation model of feral swine population dynamics which accounted for social dynamics in space. We tested the impacts of different spatio-temporal management strategies (i.e., culling rates, timing of culling during the year, spatial pattern of culling and strength of a barrier to immigration) on population response and efficiency. The spatial culling strategy dramatically impacted efficiency of control – using zonation required removal of fewer pigs (up to 46% less) to achieve similar reductions compared with other spatial strategies. Also, our spatially-explicit model predicted that lower culling intensities could be used to achieve population reductions when zonation was applied relative to predictions from harvesting theory based on simple logistic models. As culling intensity increased (≥50% of target population annually) and the target population reached low density (<5% of original density), effects of spatial strategy became less pronounced relative to immigration barrier effects. Lastly, for the same level of moderate culling effort, prioritization of culling during the low-birthing period generally resulted in faster population reduction to near zero abundance relative to prioritization during the high-birthing period, or spreading the work over a year period, but the significance of this effect depended on the spatial culling strategy and culling intensity. Our results imply that continually updating knowledge of current abundance during management may not only be important for determining culling quotas, but also for updating and optimizing management strategies. When the management goal is maximum population control, consideration of birth and spatial dynamics can increase return on management effort and bring to light management inefficiencies.

EVIDENCE OF PSEUDORABIES VIRUS SHEDDING IN FERAL SWINE ( SUS SCROFA) POPULATIONS OF FLORIDA, USA.

: Feral swine ( Sus scrofa) are a pathogen reservoir for pseudorabies virus (PrV). The virus can be fatal to wildlife and contributes to economic losses in the swine industry worldwide. National surveillance efforts in the US use serology to detect PrV-specific antibodies in feral swine populations, but PrV exposure is not a direct indicator of pathogen transmission among conspecifics or to non-suid wildlife species. We measured antibody production and the presence of PrV DNA in four tissue types from feral swine populations of Florida, US. We sampled blood, nasal, oral, and genital swabs from 551 individuals at 39 sites during 2014-16. Of the animals tested for antibody production, 224 of 436 (51%) feral swine were antibody positive while 38 of 549 feral swine (7%) tested for viral shedding were quantitative polymerase chain reaction (qPCR)-positive for PrV. The detection of PrV DNA across all the collected sample types (blood, nasal, oral, and genital [vaginal] swabs) suggested viral shedding via direct (oronasal or venereal), and potentially indirect (through carcass consumption), routes of transmission among infected and susceptible animals. Fourteen of 212 seronegative feral swine were qPCR-positive, indicating 7% false negatives in the serologic assay. Our findings suggest that serology may underestimate the actual infection risk posed by feral swine to other species and that feral swine populations in Florida are capable of shedding the virus through multiple routes.

Development of the national feral swine map, 1982–2016

ABSTRACTThe Southeastern Cooperative Wildlife Disease Study developed the first national feral swine (Sus scrofa) map for the United States in 1982 in collaboration with state wildlife resources agencies. National feral swine distribution maps were completed in 1982, 1988, and 2004 as individual maps, and then annually beginning in 2008 through the National Feral Swine Mapping System (NFSMS). The NFSMS is an internet‐based data‐collection website used in collaboration with state wildlife resources agencies and the U.S. Department of Agriculture, Animal and Plant Health Inspection Service. These ongoing collaborations have provided for a long‐term database that documents the expansion of established feral swine populations in the United States. The number of states reporting established populations was 18 in 1982 and 35 in 2016. The geographic area included in the distribution of feral swine increased from 544,854 km2 in 1982 to 1,675,618 km2 in 2016. We describe the development of the national feral swine maps including details on how these data were collected; provide feral swine maps for select years from 1982 to 2016; and note some of the uses of these maps. These maps detail the expansion of feral swine since 1982, which can be used in the future to monitor increases or decreases in the distribution of feral swine as natural reproduction of feral swine continues and feral swine control programs are implemented. © 2017 The Wildlife Society.

Development of a rapid, simple, and specific real-time PCR assay for detection of pseudorabies viral DNA in domestic swine herds.

Despite successful eradication of pseudorabies virus (PRV) from the commercial pig industry in the United States in 2004, large populations of feral swine in certain regions act as wildlife reservoirs for the virus. Given the threat of reintroduction of the virus into domestic herds, a rapid, reliable, easily implemented assay is needed for detection of PRV. Although a real-time PCR (rtPCR) assay exists, improvements in rtPCR technology and a greater understanding of the diversity of PRV strains worldwide require an assay that would be easier to implement, more cost effective, and more specific. We developed a single-tube, rapid rtPCR that is capable of detecting 10 copies of PRV glycoprotein B ( gB) DNA per 20-µL total volume reaction. The assay did not produce a false-positive in samples known to be negative for the virus. The assay was negative for genetically similar herpesviruses and other porcine viruses. Our assay is a highly specific and sensitive assay that is also highly repeatable and reproducible. The assay should be a useful tool for early detection of PRV in pigs in the case of a suspected introduction or outbreak situation.

Evidence of leptospirosis in the kidneys and serum of feral swine (Sus scrofa) in the United States.

Leptospirosis is the most widespread zoonosis in humans worldwide. In the United States, widespread detection of antibodies to leptospirosis have been identified in feral swine (Sus scrofa) with the highest detection of serovars, Bratislava, Icterohaemorrhagiae, and Pomona. Over the past few years, feral swine populations have expanded their geographical range and distribution in the United States with reports in at least 39 of 50 states. Since feral swine serve as reservoirs for serovars that can infect humans, it is important to understand the risk of transmission. In order to learn more about the probability that feral swine shed infectious leptospires, we collected kidneys and paired serum when possible from 677 feral swine in 124 counties of 29 states. These counties had previously been identified as antibody positive for Leptospira interrogans serovars Bratislava, Canicola, Grippotyphosa, Hardjo, Icterohaemorrhagiae or Pomona. Although exposure to these same six serovars of leptospirosis continued to be high (53% overall) in the counties we sampled, we detected leptospiral DNA in only 3·4% of feral swine kidneys tested. Based on these results, it appears that although feral swine can serve as a source of infection to humans, especially in those who are more likely to encounter them directly such as wildlife biologists, veterinarians, and hunters, the risk may be relatively low. However, further studies to examine the relationship between leptospiral shedding in the urine and kidneys in addition to culturing the organism are recommended in order to better understand the risk associated with feral swine.

Disease-emergence dynamics and control in a socially-structured wildlife species.

Once a pathogen is introduced in a population, key factors governing rate of spread include contact structure, supply of susceptible individuals and pathogen life-history. We examined the interplay of these factors on emergence dynamics and efficacy of disease prevention and response. We contrasted transmission dynamics of livestock viruses with different life-histories in hypothetical populations of feral swine with different contact structures (homogenous, metapopulation, spatial and network). Persistence probability was near 0 for the FMDV-like case under a wide range of parameter values and contact structures, while persistence was probable for the CSFV-like case. There were no sets of conditions where the FMDV-like pathogen persisted in every stochastic simulation. Even when population growth rates were up to 300% annually, the FMDV-like pathogen persisted in <25% of simulations regardless of transmission probabilities and contact structure. For networks and spatial contact structure, persistence probability of the FMDV-like pathogen was always <10%. Because of its low persistence probability, even very early response to the FMDV-like pathogen in feral swine was unwarranted while response to the CSFV-like pathogen was generally effective. When pre-emergence culling of feral swine caused population declines, it was effective at decreasing outbreak size of both diseases by ≥80%.

Effects of simulated removal activities on movements and space use of feral swine

Abundance and distribution of feral swine (Sus scrofa) in the USA have increased dramatically during the last 30 years. Effective measures are needed to control and eradicate feral swine populations without displacing animals over wider areas. Our objective was to investigate effects of repeated simulated removal activities on feral swine movements and space use. We analyzed location data from 21 feral swine that we fitted with Global Positioning System harnesses in southern MO, USA. Various removal activities were applied over time to eight feral swine before lethal removal, including trapped-and-released, chased with dogs, chased with hunter, and chased with helicopter. We found that core space-use areas were reduced following the first removal activity, whereas overall space-use areas and diurnal movement distances increased following the second removal activity. Mean geographic centroid shifts did not differ between pre- and post-periods for either the first or second removal activities. Our information on feral swine movements and space use precipitated by human removal activities, such as hunting, trapping, and chasing with dogs, helps fill a knowledge void and will aid wildlife managers. Strategies to optimize management are needed to reduce feral swine populations while preventing enlarged home ranges and displacing individuals, which could lead to increased disease transmission risk and human-feral swine conflict in adjacent areas.

Bait Preference of Free-Ranging Feral Swine for Delivery of a Novel Toxicant.

Invasive feral swine (Sus scrofa) cause extensive damage to agricultural and wildlife resources throughout the United States. Development of sodium nitrite as a new, orally delivered toxicant is underway to provide an additional tool to curtail growth and expansion of feral swine populations. A micro-encapsulation coating around sodium nitrite is used to minimize detection by feral swine and maximize stability for the reactive molecule. To maximize uptake of this toxicant by feral swine, development a bait matrix is needed to 1) protect the micro-encapsulation coating so that sodium nitrite remains undetectable to feral swine, 2) achieve a high degree of acceptance by feral swine, and 3) be minimally appealing to non-target species. With these purposes, a field evaluation at 88 sites in south-central Texas was conducted using remote cameras to evaluate preferences by feral swine for several oil-based bait matrices including uncolored peanut paste, black-colored peanut paste, and peanut-based slurry mixed onto whole-kernel corn. These placebo baits were compared to a reference food, whole-kernel corn, known to be readily taken by feral swine (i.e., control). The amount of bait consumed by feral swine was also estimated using remote cameras and grid boards at 5 additional sites. On initial exposure, feral swine showed reduced visitations to the uncolored peanut paste and peanut slurry treatments. This reduced visitation subsided by the end of the treatment period, suggesting that feral swine needed time to accept these bait types. The black-colored peanut paste was visited equally to the control throughout the study, and enough of this matrix was consumed to deliver lethal doses of micro-encapsulated sodium nitrite to most feral swine during 1–2 feeding events. None of the treatment matrices reduced visitations by nontarget species, but feral swine dominated visitations for all matrices. It was concluded that black-colored peanut paste achieved satisfactory preference and consumption by feral swine, and no discernable preference by non-target species, compared to the other treatments.

Overview of Feral Swine Management and Elimination Efforts in New York (2008-2016)

Author(s): Jackling, Mark E.; Gansowski, Justin T.; Hojnacki, Daniel M.; Gosser, Allen L. | Abstract: State officials first discovered free-roaming feral swine breeding in New York from 2000-2005. Escapes from highfence shooting facilities and Eurasian wild boar breeding operations, as well as intentional releases to create new hunting opportunities, allowed these animals to become established in four distinct populations. Utilizing a strategy of “whole sounder” management, in which entire family groups of swine are captured all at once, USDA APHIS, Wildlife Services and the New York State Department of Environmental Conservation removed 209 feral swine from 2008-2014. It appears that feral swine populations were eliminated from New York, as there have been no confirmed sightings since October 2014. Wildlife Services is leading a multi-faceted monitoring effort that includes the use of trail cameras, aerial surveys, detection dog surveys, and the development of an early detection network to reduce the risk of a reinvasion caused by failure to detect the last remaining individuals. Additionally, New York addressed the problem at its roots by passing legislation that prohibits hunting, propagation, trade, and possession of Eurasian wild boars and Eurasian wild boar hybrids. Much of the state’s feral swine elimination program success is attributed to lessons learned from successes and failures of past and ongoing wild pig elimination campaigns around the world. New York encountered unique challenges requiring innovative solutions that are informative to future invasive species eradication efforts. We provide an overview of the New York efforts to eliminate feral swine with an emphasis on education/outreach, regulatory action, lethal control, and monitoring.

Ixodid Ticks on Feral Swine and Other Mammals in South-Central Florida

Author(s): Merrill, Mary M.; Lord, Cynthia C.; Turner, E. Lynn; Boughton, Raoul K.; Hernandez, Felipe A.; Wisely, Samantha M. | Abstract: Feral swine in the United States are known to harbor both native and exotic Ixodid ticks. The expanding range, broad habitat use, high population potential, and large movements of feral swine may increase the distribution and density of certain tick species and tick-borne pathogens that can infect humans, livestock, and wildlife. This preliminary study was conducted to determine which tick species are present on feral swine as well as other mammals sympatric with feral swine in south-central Florida. We trapped large-, medium-, and small-bodied mammals at two study sites, Kissimmee Prairie Preserve State Park and MacArthur Agro-ecology Research Center, from February to May of 2014. We examined mammals for ticks and conducted drags for host-seeking ticks. We trapped five mammal species (feral swine, Florida mouse, marsh rice rat, Virginia opossum, and northern raccoon). From these animals we identified four native tick species (Amblyomma americanum, A. maculatum, Dermacentor variabilis, and Ixodes scapularis) and one exotic to the United States (A. auricularium). We also obtained carcasses of nine-banded armadillos in Brevard County, on which we found A. auricularium. This is the first report of I. scapularis in Okeechobee County and A. auricularium in Brevard and Highlands Counties. All four native tick species are known disease vectors. These data reiterate that many mammals that share habitat with livestock and commonly contact humans are hosts to many ticks of medical and veterinary importance. Coupled with the population, distribution potential, and movement of feral swine, the diversity of ticks found in this study highlights the need for further research on the ability of feral swine to host and distribute ticks and tick-borne pathogens among wildlife, livestock, and humans.

Dynamics of virus shedding and antibody responses in influenza A virus-infected feral swine.

Given their free-ranging habits, feral swine could serve as reservoirs or spatially dynamic 'mixing vessels' for influenza A virus (IAV). To better understand virus shedding patterns and antibody response dynamics in the context of IAV surveillance amongst feral swine, we used IAV of feral swine origin to perform infection experiments. The virus was highly infectious and transmissible in feral swine, and virus shedding patterns and antibody response dynamics were similar to those in domestic swine. In the virus-inoculated and sentinel groups, virus shedding lasted ≤ 6 and ≤ 9 days, respectively. Antibody titres in inoculated swine peaked at 1 : 840 on day 11 post-inoculation (p.i.), remained there until 21 days p.i. and dropped to < 1 : 220 at 42 days p.i. Genomic sequencing identified changes in wildtype (WT) viruses and isolates from sentinel swine, most notably an amino acid divergence in nucleoprotein position 473. Using data from cell culture as a benchmark, sensitivity and specificity of a matrix gene-based quantitative reverse transcription-PCR method using nasal swab samples for detection of IAV in feral swine were 78.9 and 78.1 %, respectively. Using data from haemagglutination inhibition assays as a benchmark, sensitivity and specificity of an ELISA for detection of IAV-specific antibody were 95.4 and 95.0 %, respectively. Serological surveillance from 2009 to 2014 showed that ∼7.58 % of feral swine in the USA were positive for IAV. Our findings confirm the susceptibility of IAV infection and the high transmission ability of IAV amongst feral swine, and also suggest the need for continued surveillance of IAVs in feral swine populations.

Facts about Wildlife Diseases: Pseudorabies

Pseudorabies primarily affects swine, but cattle, sheep and other mammals are susceptible to infection. Humans are not at risk. The superficial symptoms of this viral disease resemble rabies symptoms, thus the name pseudorabies. Although eliminated in commercial animals, feral swine populations in the United States continue to circulate the disease and provide a reservoir for outbreaks. Texas, Oklahoma, Florida, and Hawaii all have dense populations of feral swine with a high prevalence of pseudorabies. Feral swine, therefore, pose a serious risk to commercial swine operations, livestock, companion animals, and wildlife. This 4-page fact sheet was written by Samantha Wisely and published by the UF Department of Wildlife Ecology and Conservation, August 2014.

Governmental provisions to manage and eradicate feral swine in areas of the United States.

Feral swine (wild hogs) are one of the most widely distributed free-ranging mammals in the world. In the United States, feral swine serve as game animals for the sport of hunting in some areas, while they are nuisance species at other locations. Increasing feral swine populations creates negative impacts to growing crops, native plant communities, and wildlife. Feral swine can also serve as reservoirs for a number of bacterial and viral diseases that can infect wild animals, livestock, and humans. The US state governments are adopting statutes and regulations to reduce the growth and dispersal of feral swine populations. An analysis of these provisions suggests that while they seek to control feral swine populations, they are unlikely to provide any significant relief from damages to crops and native ecosystems. More localized reduction plans and a national disease control program are suggested to assuage damages being wrought by these invasive animals.

Impacts from control operations on a recreationally hunted feral swine population at a large military installation in Florida

Feral swine were targeted for control at Avon Park Air Force Range in south-central Florida to avert damage to sensitive wetland habitats on the 40,000-ha base. We conducted a 5-year study to assess impacts from control to this population that had been recreationally hunted for many years. Control was initiated in early 2009. The feral swine population was monitored from 2008 to 2012 using a passive tracking index (PTI) during the dry and wet seasons and using recreational hunter take rates from the dry season. All three indices showed substantial feral swine declines after implementing control, with indices leveling for the final two study years. Military missions and recreational hunting seasons impacted temporal and spatial consistency of control application, thereby limiting further impacts of control efforts on the feral swine population. The PTI was also able to monitor coyotes, another invasive species on the base, and detect Florida black bear and Florida panther, species of particular concern.

IDENTIFICATION OFBRUCELLA SUISFROM FERAL SWINE IN SELECTED STATES IN THE USA

Serologic tests currently available for brucellosis diagnosis detect antibodies to Brucella but do not distinguish between species of Brucella. Although Brucella suis is known to circulate within various feral swine (Sus scrofa) populations, our objective was to determine the primary species of Brucella circulating in feral swine populations in areas of the US with high brucellosis prevalence. We cultured lymph nodes from 183 feral swine. We identified 22 isolates from 21 animals, and all isolates were genotyped as B. suis. Most isolates were B. suis biovar 1, with the exception of two genetically distinct isolates from one feral swine in Hawaii, which were identified as B. suis biovar 3. Serum from each feral swine was also tested by the fluorescence polarization assay when possible, but only 52% (95% CL = 29.8-74.3) of culture-positive animals were antibody positive. Our results indicate that brucellosis infections in feral swine within the US are typically caused by B. suis. However, improved serologic tests are needed to more accurately determine exposure to Brucella spp. and to monitor disease trends in feral swine populations.

Wildlife Reservoirs of Livestock Disease: Planning Responses to Suspected Outbreaks of Classical Swine Fever in Feral Swine

Author(s): Ward, Alastair I.; Massei, Giovanna; Cowan, David P. | Abstract: Food security and international trade require healthy livestock. A wildlife reservoir can compromise control of livestock disease. When disease is suspected in wildlife, initial questions include whether their behaviour, ecology and proximity to livestock pose a significant risk. Then, what options are there for mitigating risk? If we respond, how should we measure success? Following action, lessons must be learned so that we are more effective during the next disease outbreak. At least 4 discrete populations of feral swine currently exist in England at relatively low densities. In the event of a suspected classical swine fever (CSF) outbreak, investigation zones and control strategies may need to be initiated, and so new models need to be created to fit these English populations. Here, we present an approach to using data collected during scientific research projects and wildlife management exercises to aid decisions on how to resource a program of disease detection and control if CSF was suspected to have broken out in feral swine populations in England. Culling efficiency was estimated through trapping and shooting records. Results were used to create predictive models which determined resources and costs required to carry out an efficient cull within various possible scenarios. Trapping over 26 months at one 427-ha site resulted in the capture of 130 swine at an average of 0.21 swine per trap-night and US$477 per animal. Shooting by two government hunters over 12 months at another site resulted in the culling of 56 swine, equating to 1 swine shot for every 18 hrs 40 mins; total effort was 41 hrs 44 mins with total cost around US$75,628 (US$1,350) per animal. Using simulation models, we estimated the costs of delivering a cull via a combined approach of trapping and shooting to detect CSF at 1% and 5% seroprevelance. Costs ranged widely, depending on scenario, with minimum costs of US$51,404 and $69,029, and maximum costs of US$231,545 and $203,109, respectively. Results suggest that at present it is feasible to deliver a sampling strategy that could detect and potentially resolve the occurrence of CSF in feral swine in England.

First Reports of Pseudorabies and Winter Ticks (Dermacentor albipictus) Associated with an Emerging Feral Swine (Sus scrofa) Population in New Hampshire

The expansion of feral swine (Sus scrofa) populations into new geographic regions is of concern not only due to increased range but also because they carry diseases and parasites that pose a threat to humans, livestock, and wildlife into new areas. Recently, emerging feral swine populations have been reported in the northeastern US and due to their adaptive nature will likely continue to spread. During 2009-2012, 49 feral swine were removed from three counties in New Hampshire. Of these, serum samples were submitted from 34 for disease surveillance testing. One of the feral swine was antibody-positive for pseudorabies virus (PRV) making it the first documented infection in feral swine in New Hampshire. Infestations of winter tick (Dermacentor albipictus) were also documented on two of the feral swine which had only been reported previously on feral swine in Texas. Feral swine may not only serve as an important host for an economically important commercial swine pathogen like PRV, but they could also increase host diversity for parasites such as the winter tick, a species that can regionally impact moose (Alces alces) survival. These findings warrant further investigation of expanding and established feral swine populations in New Hampshire as pathogen hosts and support continued effort to reduce numbers or regionally eradicate feral swine.