Top Topics Exotics - Top 6 Cervid Diseases Flashcards
what animals are affected by chronic wasting disease?
white tailed deer, mule deer, elk, & moose - due to the long incubation period, affected animals are over 16 months of age
what is the classic case presentation of chronic wasting disease in cervids?
weight loss, behavior changes, neurologic signs, pu/pd, & aspiration pneumonia is common
what is the etiology of CWD?
misfolded prion protein
how is CWD diagnosed? what test is used for screening?
immunohistochemistry is preferred, ELISA used for screening, or western blot at USDA certified labs (retropharyngeal lymph node especially in white tail deer & mule deer & obex)
what is done for surveillance of CWD?
surveillance: heads provided by hunters & biopsies are done on tonsils, retropharyngeal lymph nodes, & recto-anal mucosa-associated lymphoid tissue
how is CWD controlled?
no treatment - control includes voluntary national CWD herd certification program either by state or herd owner with fencing requirements, individual animal identification, & testing on all animals that die after 12 months of age & surface disinfection with 50% bleach for 30-60 minutes or 1 M sodium hydroxide for 60 minutes
how is carcass disposal done for animals with CWD?
incineration or alkaline digestion
what was the first case of CWD seen in?
mule deer from northern colorado in 1967
how does CWD go through horizontal transmission?
ingestion of urine or feces on forage
T/F: CWD is a reportable disease
TRUE
what is the meningeal worm that affects cervids?
paralestrongylus tenuis
what animals are usually asymptomatic when affected with meningeal worms?
white tail deer
what are aberrant cervid hosts that show clinical signs from meningeal worms?
moose, mule deer, elk, or caribou
what clinical signs are seen with meningeal worm infections in cervids?
lumbar weakness, ataxia, circling, abnormal head positions, paralysis, slow movement, & less wary of humans, - may also have cortical blindness or may see a temporary remission
how are meningeal worms in cervids diagnosed?
CSF analysis, a pleocytosis that may be eosinophilic, elevated protein, & maybe xanthochromia
what is seen on necropsy from a cervid with meningeal worms?
threadlike adult worm in subdural space in white tailed deer but are in the CNS parenchyma of aberrant hosts
how are meningeal worms treated in cervids?
fenbendazole or ivermectin
what is the life cycle of the meningeal worm?
adults lay eggs in white tail deer dura mater which hatch into L1 and are carried to lungs, larvae migrate up bronchial tree and swallowed, larvae exit the deer in mucus coating of feces, snails/slugs feed on the mucus fecal coating & become intermediate hosts where L2 & L3 develop, & white tail deer or aberrant host ingests intermediate hosts or their slime secretions as they graze
what are the main hemorrhagic diseases of cervids? what is important to remember about them? what cervid is most severely affected?
bluetongue & epizootic hemorrhagic disease - clinically indistinguishable from each other
what are the main clinical signs associated with bluetongue & epizootic hemorrhagic disease in cervids?
white tail deer most severely affected - loss of fear of humans, hypersalivation, anorexia, marked head/neck edema, bloody diarrhea, fever, tachycardia, erosions/ulcerations of oral cavity, & death within 36 hours or may follow a chronic course
why are deer dead from epizootic hemorrhage often found in water?
they make an attempt to lower their body temp
