characterization of the second internal transcribed spacer (its-2)rdna region among the elaphostrongylinae (nematoda:protostrongylidae)
abstract
four species of elaphostrongyline nematodes are known to infect cervids in north
america. one species, parelaphostrongylus tenuis, can cause neurologic disease
(parelaphostrongylosis) in cervid hosts other than white tailed deer. another, elaphostrongylus
rangiferi, can cause cerebrospinal elaphostrongylosis (cse) in young, heavily infected caribou.
the remaining species, p. andersoni and p. odocoilei do not cause neurologic disease but can
cause verminuous pneumonia. moreover, two european species, e. cervi and e. alces, are
capable of infecting north american cervid populations if they enter with imported game
animals, such as red deer. differentiation of these species is problematic as they all produce first stage
larvae (li) that are morphologically indistinguishable. this is a major concern for wildlife
biologists who attempt to identify and limit the spread of pathogenic nematodes in north
america.
this study improves upon existing methods of extraction and amplification of
protostrongylid dna by addressing the difficulties of obtaining dna data from preserved as
well as single nematodes, both adult and larval. a modified commercial kit extraction and
purification procedure (qiaamp, qiagen, valencia, california) was developed and pcr
parameters, such as cycling temperatures and times, were optimised to address these difficulties.
second internal transcribed spacer (tts-2) rdna sequence data was obtained for all six
elaphostrongyline species as well as an unidentified nematode from bighorn sheep in
washington. elaphostrongylus cervi and e. rangiferi are both 585 base pairs (bp) long, e. alces
is 575 bp, p. tenuis is 554 bp, p. andersoni is 545 bp, and p. odocoilei is 561 bp long.
collections
- retrospective theses [1604]