SEAFWA 2015

Susan R. Sullivan, William C. Bridges Jr. – Clemson University; Katherine W. McFadden, South Carolina Cooperative Fish & Wildlife Research Unit, Clemson University; John J. Mayer, Savannah River National Laboratory; Patrick G.R. Jodice, South Carolina Cooperative Fish & Wildlife Research Unit, Clemson Univeristy; Greg K. Yarrow, Clemson University

The wild hog (Sus scrofa) is an invasive species that can pose a serious threat to native ecosystems, the domestic livestock industry, and human health. It is estimated that wild hog damage in the United States amounts to roughly $1.5 billion each year; however, this estimate could substantially increase if wild hogs transmitted a viral or bacterial disease to the country’s domestic livestock industry. From 2007-2014, blood and nasal secretion samples were collected from 753 wild hogs in South Carolina to test for 6 selected diseases including classical swine fever, swine brucellosis, pseudorabies virus, porcine circovirus, porcine reproductive and respiratory syndrome, and swine influenza virus all of which can be transmitted to domestic livestock. The sex, age class, and geographic location of each wild hog sampled were also recorded. Results indicate that age class was significantly associated with swine brucellosis, pseudorabies virus, and porcine circovirus prevalence. Sex was significantly associated with porcine circovirus prevalence as well. Positive swine brucellosis, pseudorabies virus, and porcine circovirus samples were found in 44.4-92.3% of counties sampled. All domestic swine operations in the United States are currently free of swine brucellosis and pseudorabies virus; however, our results suggest that wild hogs could be reservoirs of these diseases with the potential to infect domestic livestock. Because wild hogs are present in every county of South Carolina, this information is crucial to determine disease hotspots in the state and can be shared with at-risk individuals, such as hunters or farmers, and domestic livestock operations in affected counties.

Jordona D. Kirby, Kathleen M. Nelson, Dennis Slate, Richard B. Chipman –USDA, APHIS, Wildlife Services, National Rabies Management Program

Rabies remains a significant public health and wildlife management challenge in the U.S., with costs of managing rabies exceeding $300 million annually. Oral rabies vaccination (ORV) began in the 1990s, to prevent the raccoon (Procyon lotor) rabies variant from spreading to populated areas in New Jersey and Massachusetts. USDA, APHIS, Wildlife Services’ (WS) involvement in ORV began in Texas during 1995 to prevent the spread of canine rabies variant in coyotes (Canis latrans). Wildlife Services received its first federal appropriation for rabies management in 1998, and the program expanded with a primary focus on preventing the westward spread of raccoon rabies. In 2015, WS and cooperators distributed >10.1 million baits to combat raccoon rabies in 14 eastern states, and canine, gray fox (Urocyon cinereoargenteus) and skunk (Mephitis mephitis) rabies in Texas. Enhanced rabies surveillance includes testing of suspicious-acting and road-killed animals within proximity to ORV zones and other strategic areas. Enhanced surveillance coupled with public health surveillance provides more comprehensive information on the spatial distribution of rabies. From 2005-2014, WS collected >82,000 surveillance samples from 24 states and tested 83% with a field-based diagnostic test. Fifteen of 24 states confirmed 1,274 rabid animals that would not have been tested through traditional public health surveillance. The ORV program has led to: no appreciable spread of raccoon rabies, elimination of canine rabies in coyotes, and near elimination of gray fox rabies in Texas. The WS rabies management program represents one of the largest coordinated landscape-level wildlife disease management programs in North America.

Dusty J. Harrell, Jean Fantle-Lepczyk, Todd D. Steury –Auburn University

Non-invasively collected fecal samples are an important method of monitoring wildlife species. However, similarity in feces appearance amongst sympatric species can complicate identification and thus negatively impact accuracy of estimates generated. In order to efficiently and unambiguously identify carnivore species from fecal DNA samples, Bidlack et al (2007) developed a PCR-RFLP protocol to distinguish among a suite of western North American carnivores. While the technique was effective for the seven species included in the study, we investigated how the technique would apply to carnivore species in the southeastern US. We collected tissue and scat samples from Alabama populations of Bidlack et al’s (2007) seven carnivore species, as well as samples from three additional carnivore species (black bear, domestic dog, and domestic cat) that are locally common and that could potentially complicate the identification process. We extracted DNA using QiaAMP stool and tissue DNA extraction kits by Qiagen. We used polymerase chain reaction (PCR) to amplify a 196 base pair polymorphic region of cytochrome b from the extractions. We then evaluated how three restriction enzymes (HpaII, DdeI, HpyCH4V) would cut the amplified region at species-specific locations. Using this technique, we were able to distinguished among DNA from coyote, grey fox, striped skunk, domestic dog, opossum, and river otter. However, bobcat and domestic cat cut in the same location, as did black bear and raccoon. Thus, this method can potentially be an accurate and inexpensive method of identifying carnivore scat in the southeastern U.S. However care must be taken to consider limitations.

Chad N. Smith, Missouri Department of Conservation

The Missouri Department of Conservation (MDC) has been testing for the presence of Chronic Wasting Disease (CWD) in the state since 2002 and has collected more than 43,000 samples. The first case of CWD in Missouri was detected in a captive white-tailed deer in February of 2010 in Linn County. Since that time, MDC has conducted intensive targeted sampling near the location of CWD positive captive and free-ranging deer. Over the last five years, in the vicinity of detected positive cases, MDC has worked cooperatively with hunters, landowners, businesses and citizens to determine prevalence and distribution of the disease. MDC has invested significant staff time and resources in collecting samples during fall hunting seasons. MDC has also coordinated additional post-hunting season sampling efforts. All of these sampling efforts have impacted the work loads and priorities of many MDC staff with the greatest impact being on staff whose duty assignments are closest to the locations where the disease has been detected. These staff are responsible for leading on-the-ground sample collection activities. In total, nearly 550 MDC staff have logged more than 67,000 hours at an estimated cost of 1.2 million dollars since confirmation of the first positive in February of 2010. CWD sample collection and disease detection requires a multifaceted approach. During the firearms deer hunting season, MDC staff collect samples in the field from hunter-harvested deer and from deer brought to commercial meat processors. In addition, taxidermists are contracted to collect and submit samples to the MDC Wildlife Health Unit. After the close of Missouri’s deer hunting seasons, MDC staff and cooperating landowners conduct targeted culling of deer in areas near confirmed positive CWD cases and collect additional samples. MDC has also focused on educating the public about CWD. These outreach efforts are critical and have included one-on-one contacts, numerous public meetings, media campaigns, billboards and many other activities. Monitoring CWD in Missouri has been and will continue to be a significant commitment of staff time and resources.

Maria B. Palamar, North Carolina Wildlife Resources Commision; M. Colter Chitwood, Morgan; B. Swingen, Marcus A. Lashley –North Carolina State University; James R. Flowers, Charles S. Apperson –College of Veterinary Medicine, North Carolina State University; Colleen Olfenbuttel, North Carolina Wildlife Resources Commission; Christopher E. Moorman, Christopher S. DePerno –North Carolina State University

Coyotes (Canis latrans) have recently expanded into the eastern United States and can serve as a source of pathogens to domestic dogs (Canis lupus familiaris), livestock, and humans. We examined free-ranging coyotes from central North Carolina, USA, for select parasites and seroprevalence against viral and bacterial agents of interest. Most coyotes (81%) had ticks, with Amblyomma americanum detected on 83% of those with ticks. Fifteen (47%) coyotes tested positive for heartworms (Dirofilaria immitis) with higher detection rates in adults (75% compared to 22% in juveniles). Serology revealed antibodies against canine adenovirus (71%), canine coronavirus (32%), canine distemper virus (17%), canine parvovirus (96%), and Leptospira spp. (7%). We did not detect antibodies against Brucella abortus or B. canis. Because coyotes are widespread newcomers to the eastern United States and due to their roaming behavior, they could increase the risk of infections from economically important diseases (e.g., brucellosis), thus, understanding disease presence in the coyote population is important.