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Meningeal Worm. Moose, elk, caribou, reindeer, mule deer, black-tailed deer, mule deer/white-tailed deer hybrids, fallow deer, red deer, red deer/elk hybrids, domestic sheep and goats, llamas, guinea pigs, and several bovid and cervid species in zoos
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Meningeal Worm • Moose, elk, caribou, reindeer, mule deer, black-tailed deer, mule deer/white-tailed deer hybrids, fallow deer, red deer, red deer/elk hybrids, domestic sheep and goats, llamas, guinea pigs, and several bovid and cervid species in zoos • Appears reindeer, caribou, llamas, and domestic goats are very susceptible • Speculated that caribou and reindeer may be more likely to acquire infected gastropods because of their feeding habits • Causes incoordination, circling, recumbency, paralysis
Meningeal Worm • thousands of eggs per gram of deer feces • larvae are highly resistant to environmental forces • weather dependent (wet and cool) – support high gastropod abundance
Meningeal Worm • Distribution of meningeal worm in eastern and western South Dakota. Note separation of eastern from western South Dakota by the Missouri River. (Christopher and Jenks 2004. Journal of Wildlife Diseases, 40:133-136)
Raccoon Roundworm midwestern U.S. documented in 68–82% of raccoons
Raccoon Roundworm - Prevalence, intensity of infection, avg # of larvae significantly higher in the highly fragmented landscape. Within the agricultural landscape - Probability of infection, intensity of infection, and avg # of larvae per mouse per patch as functions of forest patch area and isolation
Raccoon Roundworm • A study conducted in Northern California tried to determine if a pattern existed to the preferred location of latrines. While latrines on the ground and on roofs appeared to be the most favorable, preferences varied by location.
Raccoon Roundworm • Percentage of Californiaproperties that contained at least one raccoon latrine positive for Baylisascaris procyonis eggs (number of properties = 164).
Raccoon Roundworm • Former range of the Allegheny woodrat (inside bold line), and regions where woodrats have disappeared in recent decades (stippled areas).
Raccoon Roundworm • Range of raccoon roundworm in Allegheny woodrat states
Sarcoptic Mange • Sarcoptes scabiei mite • Throughout year, but most commonly observed during winter months when hair loss can be life threatening • Infections found in humans (called "scabies"), wild and domestic dogs and cats, bears and mustelids • Common in red fox, wolves, and coyotes in North America • Predominantly impacts younger animals. • Highly contagious, direct transfer of mites at any stage of their development • Indirect transfer of mites (mechanical transfer) – importance?
Sarcoptic Mange • ~1/64 of an inch long • Pearly white and oval-shaped • Spines on bodies
Sarcoptic Mange • Populations of S. scabiei usually highly specific to host type, e.g., canid-adapted types specific and spread rapidly among canids • Life cycle of mite completed in burrows within epidermis of host • Adult mites mate in small pockets near the surface of the skin • Hatched larvae pass through a nymphal stage and continue migration through the epidermis, becoming adults within 2 weeks
Sarcoptic Mange • Mites use small suckers on their legs to hold onto their hosts • Female mites burrow into the skin of the host using jaws and front legs to cut the skin • Inside the burrow, the female will lay eggs. She lays 2 or 3 eggs each day, for up to 2 months. • Mite larvae hatch from the eggs in 3 or 4 days • Immediately crawl out of the burrow onto the surface of the skin, remain there using host hair as shelter. • Both larvae and adult mites eat skin cells from their hosts
Sarcoptic Mange • Oily skin, crusting, hair loss, and scab formation • Typically begin on elbows and towards the tips of the ears and can eventually involve large areas of the body • Lesions result from physical damage to the skin, irritation caused by parasite excretions, and the allergic response of the host • Hair is often lost in characteristic patterns (alopecia) • Poor body condition and listlessness may be observed in severely infected animals, exhibit abnormal behavior • Severely affected carnivores may scavenge with increased frequency • Severely affected carnivores may ultimately die from complications with mange infection or exposure to the elements that results from hair loss in winter
Sarcoptic Mange • Trichodectes canis • Dog biting louse • 2ndary infection
Sarcoptic Mange – WI Wolves • Sarcoptic mange 1st identified in a Great Lakes wolf in 1991 • Since 1991, signs of mange detected in 27% of wolves • High of 58% in 1992-1993 • 1993 = 11% decline in wolf population • Some literature suggesting population impact most severe in 2nd or 3rd year of epidemic • Also other disease testing, e.g., Lyme Disease tested positive in 48% of 69 wolf serum samples • Impacts on annual pup survival?
Ticks • Ixodes (e.g., deer tick; Lyme disease (Borrelia burgdorferi) • Dermacentor (Am. Dog tick & Rocky Mtn wood tick); Rocky Mountain spotted fever (Rickettsia rickettsii ) • Amblyomma (e.g., lone star tick; Ehrlichiosis (Ehrlichia)
Ticks Winter tick (Dermacentor albipictus)
Ticks Winter tick (Dermacentor albipictus)
Ticks • Moose begin grooming in Jan (nymph stage) – mechanical and/or immunological irritation • Extensive grooming through Mar-Apr = destroy winter coat • Severe hair loss = gray coloration (undercoat) = "ghost moose".
Ticks Mean number of grooming episodes per hour performed by female moose during the four stages in the life cycle of the winter tick.
Gizzard Worm • Parasitic nematode • Genus Amidostomum or Epomidiostomum • 10-35 mm, can be coiled, thread-like roundworm • Beneath surface lining and grinding pads of gizzard • waterfowl
Gizzard Worm • Ingest larvae • 1st exposure on breeding grounds • Large worm burdens; reduce vigor, couple with migration, etc… • No field signs • Poor growth/weight gain in young birds? • Emaciation, general weakness • Poor digestion
Nasal Leeches • Common on birds north of the 30th parallel and in western North America • Leech (Genus Theromyzon) feeds directly on blood from the nasal passages, trachea and mucous membranes of eyes • Peak infestations during spring and summer when leeches actively seeking potential hosts and reproducing • Winter slows the metabolic rate and activity of leeches • Many aquatic birds are affected; commonly dabbling ducks (e.g., mallard, teal, wigeon, northern shoveler, etc.) and swans
Nasal Leeches • Leeches protruding from nares or attached externally • Resemble small sacks of blood • Birds vigorously shaking heads, scratching bills or sneezing • Nasal and respiratory tract infestations = labored breathing and gaping (similar to aspergillosis infection)
