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A.D. Boggs, C.S. DePerno, and J.R. Flowers
22001188 SOUTHEASTERN NATURALIST 1V7o(2l.) :1376,5 N–3o7. 02
Range Expansion of Fascioloides magna in North Carolina
April D. Boggs1,*, Christopher S. DePerno1, and James R. Flowers2
Abstract - 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 Whitetailed
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.
Introduction
Fascioloides magna (Bassi) (Giant Liver Fluke) is a parasite of North American
wild and domestic ruminants. Odocoileus virginianus (Zimmermann) (White-tailed
Deer) is the definitive host of Giant Liver Fluke (Pybus 2001), but little pathology
occurs in this host species. However, infections in domestic livestock cause death
or condemnation of livers (Davidson 2006, Králová-Hromadová et al. 2016, Pybus
2001, Swales 1935). Only 3 studies (Flowers 1996, Harlow and Jones 1965, Pursglove
et al. 1977) have reported Giant Liver Fluke from North Carolina.
In 2013, a fatal case of Giant Liver Fluke was diagnosed in a Lama glama L.
(Llama) from Cabarrus County, NC (NCDA Griffin Diagnostic Laboratory, Monroe,
NC). In 2014, two fatal cases of Giant Liver Fluke in Vicugna pacos (L.)
(Alpaca) were diagnosed from Franklin County, NC, and in 2016, an Ovis aries L.
(Domestic Sheep) from Wake County, NC died from a Giant Liver Fluke infection
(NCDA Rollins Diagnostic Laboratory). In addition, a Capra hircus L. (Domestic
Goat) infection and numerous Bos taurus L. (Cattle) infections have been detected
in Washington County (NCDA Rollins Diagnostic Laboratory). Livestock may
experience morbidity and mortality from liver fluke disease; thus, the range expansion
of Giant Liver Fluke is of concern, especially where wild hosts share habitat
1North Carolina State University, Department of Forestry and Environmental Resources,
Fisheries, Wildlife, and Conservation Biology, 110 Brooks Avenue, Raleigh, NC 27607.
2North Carolina State University, College of Veterinary Medicine, Department of Population
Health and Pathobiology, 1060 William Moore Drive, Raleigh, NC 27607. *Corresponding
author - adboggs@ncsu.edu.
Manuscript Editor: Roger Applegate
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2018 Vol. 17, No. 2
366
with livestock. Significant financial losses can affect livestock producers; therefore,
our objective was to document and report an increase in the historic distribution of
White-tailed Deer infected with Giant Liver Fluke in North Carolina.
Methods
From September 2014 to January 2015, we collected 165 livers from hunter-harvested
White-tailed Deer within 16 counties in North Carolina (Fig. 1). Collections
were opportunistic, based on hunter participation, and included contributions from 4
hunt clubs (Washington, Halifax, and Stanly counties), 3 nature preserves (Mecklenburg
County), 1 research station (Washington County), 1 custom processing center
(various counties), and donations from private citizens (various counties).
Our research team received White-tailed Deer livers from hunters that were
either freshly harvested or that had been stored on ice or in freezers. Livers from
the custom processor were donated directly to our research team, placed in a cooler
for transport back to our North Carolina State University (NCSU) laboratory, and
necropsied within 24 h. Livers collected in Mecklenburg County were placed on
ice, transported back to NCSU, and necropsied weekly. Other livers were collected
by hunters or hunt clubs, stored in freezers, transported to NCSU, thawed and necropsied
monthly or after the end of the hunting season. At the NCSU laboratory, we
examined the livers for signs of Giant Liver Fluke or other parasites. Besides the
number of flukes detected in each liver, we also noted pathologic signs characteristic
of Giant Liver Fluke infections, such as melanoid and fibrous tracks in the liver
tissue, liver damage, and the number of fluke pockets (Králová-Hromadová et al.
2016, Pursglove 1977, Pybus 2001, Pybus et al. 2015, Swales 1935) . We deposited
specimens (HWML 99829–99844) in the Harold W. Manter Laboratory of Parasitology.
Our parasite–host statistical analyses (prevalence and intensity) followed
Bush et al. (1997).
Results
We collected 165 livers from 16 counties and detected Giant Liver Fluke in 17
livers (10.3%) from 5 of the counties sampled (Table 1, Fig. 1). The average number
of liver flukes per infected liver was 5.4; the highest number of liver flukes was 29
in a single liver from Mecklenburg County (Table 1).
Discussion
Harlow and Jones (1965) reported a prevalence of 11.5% out of 87 North Carolina
White-tailed Deer infected with Giant Liver Fluke; however, they did not report
the counties of collection. In the 1960s and 1970s, parasitologists from North Carolina
State University conducted various surveys of helminth parasites of wildlife
in North Carolina. Giant Liver Fluke had been detected in White-tailed Deer from
hunting clubs near the towns of Roanoke Rapids and Scotland Neck, in Halifax
County (Fig. 1), but had not been detected at Fort Bragg hunting clubs in Cumberland
County (G. Miller, Emeritus, North Carolina State University, Raleigh, NC,
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2018 Vol. 17, No. 2
pers. comm.). Within the Roanoke River basin of North Carolina, Pursglove et al.
(1977) reported enzootic areas with prevalence of 56% in Halifax County, 63% in
Bertie County, and 80% in Northampton County, and a focus of infection in Bladen
County (29%) within the Cape Fear River Basin (Fig. 1). Later, Flowers (1996) reported
73% prevalence in White-tailed Deer from a hunting club in Halifax County,
near Fishing Creek, a tributary of the Tar River in North Carolina (Fig. 1).
The prevalence of Giant Liver Fluke from our study (10.3%) was similar to the
prevalence (12.8%) detected by Pursglove et al. (1977) in their study of 13 southeastern
states. However, in North Carolina, Pursglove et al. (1977) reported Giant
Liver Fluke from only 4 of 22 locations, with no Giant Liver Fluke detected east
of Bertie County or west of Bladen County (Fig.1). Our research identified Giant
Liver Fluke infections in Washington County, ~84 km (~52 mi) east of the Halifax
enzootic area; in Wake and Franklin counties, ~101 km (~63 mi) west of the Halifax
enzootic area; and in Cabarrus, Union, and Mecklenburg counties, ~322 km
(~200 mi) southwest of the Halifax enzootic area (Table 1, Fig. 1).
Of special interest is the continued enzootic status of Halifax County, in North
Carolina’s Upper Coastal Plain. The prevalence of Giant Liver Fluke in Whitetailed
Deer from Halifax County has been reported as 56% (Pursglove et al. 1977),
73% (Flowers 1996), and 70% (present study). Halifax County is bordered to the
north by the Roanoke River and only 12.5 miles to the south by Fishing Creek, a
major tributary of the Tar River. This physiography results in lowland to swampy
habitat throughout much of the county, which is excellent for the endemicity of
Giant Liver Fluke, providing browse and cover for the definitive host (i.e., Whitetailed
Deer), and slow-moving to stagnant aquatic habitat for its lymnaeid snail
host, Pseudosuccinea columnella (Say) (Mimic Lymnaea) (Flowers and Miller
1993, Walter 1954). Similar habitats, including marshlands, moist lowlands, and
swamps associated with major river drainages, have been reported as enzootic habitats
for Giant Liver Fluke (Pursglove et al. 1977, Pybus 2001, Pybus et al. 2015,
Vanderwaal et al. 2014, Vannatta 2016). Pybus et al. (2015) described the Giant
Figure 1. Collection sites of White-tailed Deer livers from September 2014 to January 2015,
and locations of previously reported Fascioloides magna (Giant Liver Fluke) infections in
North Carolina.
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2018 Vol. 17, No. 2
368
Liver Fluke ’s habitat tolerances to be relatively broad and characterized by standing
water, ubiquitous aquatic snails, and emergent vegetation.
Pursglove et al. (1977) reported Giant Liver Fluke from the Halifax enzootic
region but did not detect this fluke from collection sites outside this region (Fig. 1).
The present study reports new geographic locales, which may indicate a range expansion
of this fluke. Our White-tailed Deer and livestock reports of Giant Liver
Fluke from Franklin and Wake counties, as well as Washington County suggests expansion
west and east, respectively, from the Halifax enzootic region. Our reports
of this fluke from Cabarrus, Mecklenburg, and Union counties suggest the Giant
Liver Fluke may have dispersed into North Carolina from populations reported by
Pursglove et al (1977) in South Carolina’s Chester and Union counties.
Range expansions of the Giant Liver Fluke in North Carolina would unlikely be
due to recent expanded distributions of snail hosts, as the Mimic Lymnaea, likely
the fluke’s main snail host in North Carolina, has historically been common, ubiquitous,
and widespread (Adams et al. 1990, Flowers 1996, Flowers and Miller 1993,
Turgeon et al. 1998, Walter 1954). Although marshland habitats are important for
Giant Liver Fluke enzootic regions, Peterson et al. (2013) concluded the occurrence
of Giant Liver Fluke in Alces alces (L.) (Moose) populations was more correlated to
the population density of White-tailed Deer than the proportion of wetland habitats.
In North Carolina, White-tailed Deer populations have increased from 1976 to 2015
(NCWRC 2015), and have the potential to spread parasites and diseases, such as the
Giant Liver Fluke and tick-borne pathogens (Paddock and Yabsley 2007). Future
research is necessary to determine if the Giant Liver Fluke has expanded to other
locations in North Carolina and to understand financial impacts that infections may
have on livestock producers.
Table 1. Fascioloides magna (Giant Liver Fluke) from 17 of 165 Odocoileus virginianus (Whitetailed
Deer) collected from September 2014 to January 2015 in North Carolina.
Intensity
County Livers examined Prevalence (%) Mean Range
Beaufort 1 0.0 - -
Chatham 2 0.0 - -
Columbus 5 0.0 - -
Franklin 13 0.0 - -
Granville 5 0.0 - -
Halifax 10 70.0 3.3 1–9
Lee 1 0.0 - -
Mecklenburg 78 6.4 8.8 1–29
Moore 1 0.0 - -
Nash 1 0.0 - -
Stanly 22 0.0 - -
Union 1 100.0 6.0 -
Vance 1 0.0 - -
Wake 7 14.3 13.0 -
Warren 1 0.0 - -
Washington 15 20.0 2.0 1–4
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2018 Vol. 17, No. 2
Acknowledgments
We thank J. Tetterton, J. Bland, J. Giles, G. Marshall, J. Johnson, Pearce’s Custom
Processing, Mecklenburg Parks and Recreation, NCDA Tidewater Research Station, B.
Sherrill, M. Lashley, C. Chitwood, F. Worley, G. Gardner, T. Boggs, B. Johnson, and
B. Blackmon for helping with collecting and delivering the livers. We are grateful to hunters
from Old Church Hunt Club, Ridge Hunt Club, and Westside Hunting Club, as well
as hunters and staff at the Fork Farm, for collecting livers for the study. Also, gratitude is
extended to the NCDA Griffin Diagnostic Laboratory of Monroe, NC, and the NCDA Rollins
Diagnostic Laboratory of Raleigh for providing data on livestock cases. This project
was funded by North Carolina State University, the Fisheries, Wildlife, and Conservation
Biology Program, and the Department of Population Health and Pathobiology.
Literature Cited
Adams, W.R, J.M. Alderman, R.G. Biggins, A.G. Gerberich, E.P. Keferl, H.J. Porter, and
A.S. Van Devender. 1990. A report on the conservation status of North Carolina’s
freshwater and terrestrial molluscan fauna. The Scientific Council on Freshwater and
Terrestrial Mollusks, Raleigh, NC. 246 pp.
Bush, A.O., K.D. Lafferty, J.M. Lotz, and A.W. Shostak. 1997. Parasitology meets ecology
on its own terms: Margolis et al. revisited. Journal of Parasitology 83:575–583.
Davidson, W.R. 2006. Field Manual of Wildlife Diseases in the Southeastern United States,
3rd Editon. Southeastern Cooperative Wildlife Disease Study, The College of Veterinary
Medicine, The University of Georgia, Athens, GA. 448 pp.
Flowers, J.R. 1996. Notes on the life history of Fascioloides magna (Trematoda) in North
Carolina. Journal of the Elisha Mitchell Scientific Society 1 12:115–118.
Flowers, J.R., and G.C. Miller. 1993. Molluscs from Swift Creek, Wake, and Johnston
counties, North Carolina. Proceedings of the Annual Conference of the Southeastern
Association of Fish and Wildlife Agencies 47:359–365.
Harlow, R.F., and F.K. Jones Jr. 1965. The White-Tailed Deer in Florida. Technical Bulletin
No. 9. Florida Game Fresh Water Fish Commission, Tallahassee, FL. 240 pp.
Králová-Hromadová, I., L. Juhásová, and E. Bazsalovicsová. 2016. The Giant Liver Fluke,
Fascioloides magna: Past, Present, and Future Research. SpringerBriefs in Animal Sciences.
Springer International Publishing, Basel, Switzerland. 106 pp.
North Carolina Wildlife Resources Commission (NCWRC). 2015. Reported deer harvest
by county 1976–2015. Available online at http://www.ncwildlife.org/Portals/0/Hunting/
Documents/Deer_Reported Deer Harvest by County 1976-2015.pdf. Accessed 15
November 2016.
Paddock, C.D., and M.J. Yabsley. 2007. Ecological havoc, the rise of White-tailed Deer, and
the emergence of Amblyomma americanum-associated zoonoses in the United States.
Current Topics in Microbiology and Immunology 315:289–324.
Peterson, W.J., M.W. Lankester, J.G. Kie, and R.T. Bowyer. 2013. Geospatial analysis
of Giant Liver Flukes among Moose: Effects of White-tailed Deer. Acta Theriologica
58:359–365.
Pursglove, S.R., A.K. Prestwood, T.R. Ridgeway, and F.A. Hayes. 1977. Fascioloides magna
infection in White-tailed Deer of southeastern United States. Journal of the American
Veterinary Medical Association 171:936–938.
Pybus, M.J. 2001. Liver Flukes. Pp. 121–149, In W.M. Samuel, M.J. Pybus, and A.A.
Kocan (Eds.). Parasitic Diseases of Wild Mammals, 2nd Edition. Iowa State University
Press, Ames, IA. 559 pp.
Southeastern Naturalist
A.D. Boggs, C.S. DePerno, and J.R. Flowers
2018 Vol. 17, No. 2
370
Pybus, M.J., E.W. Butterworth, and J.G. Woods. 2015. An expanding population of the Giant
Liver Fluke (Fascioloides magna) in Elk (Cervus canadensis) and other ungulates
in Canada. Journal of Wildlife Diseases. 51:431–445.
Swales, W.E. 1935. The life cycle of Fascioloides magna (Bassi, 1875), the large liver fluke
of ruminants in Canada. Canadian Journal of Research 12:177–215.
Turgeon, D.D., J.F. Quinn, Jr., A.E. Bogan, E.V. Coan, F.G. Hochberg, Jr., W.G. Lyons,
P.M. Mikkelsen, R.J. Neves, C.F.E. Roper, G. Rosenberg, B. Roth, A. Scheltema, F.G.
Thompson, M. Vecchione, and J.D. Williams. 1998. Common and Scientific Names of
Aquatic Invertebrates from the United States and Canada: Mollusks, 2nd Edition. American
Fisheries Society Special Publication 26. American Fisheries Society, Bethesda,
Md. 536 pp.
Vanderwaal, K.L., S.K. Windels, B.T. Olson, J.T. Vannatta, and R. Moen. 2014. Landscape
influence on spatial patterns of meningeal worm and liver-fluke infection in White-tailed
Deer. Parasitology. 142:706–718.
Vannatta, J.T. 2016. The Giant Liver Fluke: A review, intermediate host habitat, and infection
in a White-tailed Deer population in Minnesota. M.Sc. Thesis. University of Minnesota,
Duluth, MN. 137 pp.
Walter, W.M. 1954. Mollusks of the upper Neuse River, North Carolina. Ph.D. Dissertation.
Duke University, Durham, NC. 219 pp.