TABLE 1.

Serial passage details of individual CWD-positive cervid animal brain homogenates inoculated into Sg hamsters

CWD inoculumPrimary passageSecond passageThird Passage
Species inoculatedaNo. of animals with TSE signs/no. inoculatedbNo. of blot-positive animals/no. testedcIncubation time (dpi) of blot-positive samplesfDonor animal inoculum (dpi)eSpecies inoculatedaNo. of animals with TSE signs/no. inoculatedbNo. of blot-positive animals/no. testedIncubation time of animals with TSE signs (mean dpi ± SD)Donor animal inoculumeSpecies inoculatedaNo. of animals with TSE signs/no. inoculatedbIncubation time of animals with TSE signs (mean dpi ± SD)
eSg ha0/72/7381, 668e 1 (381)Sg ha8/86/6427 ± 53e 1aSg ha6/6463 ± 21
e 1bSg ha4/4423 ± 28
e 1bTg (haPrP) mo3/3376 ± 8
mdSg ha2/74/7172,* 274, 326,* 393 (291 ± 93)md 1 (172)Sg ha8/82/285 ± 0md 1aSg ha6/689 ± 0
md 2 (326)Sg ha8/82/285 ± 0md 2aSg ha6/689 ± 0
wdSg ha0/80/8NonedNot doneNot done
  • a Sg ha, Sg hamster; Tg (haPrP) mo, Tg mouse with mouse PrP gene knocked out and Sg hamster PrP gene inserted (18).

  • b For each group, 12 animals were inoculated for the first passage, 8 animals were inoculated for the second passage, and six Sg hamsters or four Tg (haPrP) mice were inoculated for the third passage. Animals lost due to intercurrent deaths were not included in these data. Intercurrent deaths are defined as animals that died without neurological signs prior to the date that the first animal in the group was determined to be TSE positive by either neurological signs or brain PrP-res by immunoblot analysis.

  • c During the first passage, all animals with neurological signs were PrP-res positive, but not all brain PrP-res immunoblot-positive animals had neurological signs.

  • d The animals in this group did not have neurologic signs and were not positive for brain PrP-res during their life span (range, 351 to 553 dpi; mean, 451 ± 62 dpi).

  • e The code designates the individual Tg (haPrP) mouse or Sg hamster that was used as a source of inoculum in the passage specified. For example, “e 1” designates an individual TSE-positive Sg hamster that had been inoculated with eCWD and was used as the source of inoculum for a second passage; “e 1a” designates an individual Sg hamster from the second passage that had been inoculated from the “e1” Sg hamster.

  • f The days to death for the individual animals displaying neurological signs consistent with TSE disease are indicated by asterisks. Brain homogenates from each of these were inoculated into groups of eight Sg hamsters for the second passage.