http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Comparative study of cervid Babesia isolates
xii, 105 leaves : illustrations ; 28 cm.
Isolations of Babesia spp. were made from wild Cervidae and
the parasites were established in vitro culture. The
parasites isolated were Babesia odocoilei from white-tailed
deer (Odocoileus virginianus), and uncharacterized Babesia
spp. from an elk (Cervus elaphus canadensis) and a caribou
(Rangifer tarandus cafibou). The three cervid isolates were
morphologically closely similar to one another and were
comparable in size to B. &vergens, which is classified as a
"small" babesia. Like B. &vergens, the cervid parasites are
often found situated in close proximity to the peripheral
margin within the host erythrocyte. Relationships between
the cervid isolates and B. divergens were compared on the
basis of the following characteristics; (a) the ability of
the parasites to utilize serum and erythrocytes from
different hosts during in vitro culture, (b) the serological
profiles seen in calves (Bos taurus and Cervus elaphus
elaphus) after in vivo inoculation of the parasites, (c) the
ultrastructural characteristics of the organisms and (d) the
sequences of their small subunit ribosomal RNA (srRNA) genes.
Slight differences were found among the cervid isolates in
their ability to utilize alternate host serum and
erythrocytes in vitro. Babesia divergens was able to
propagate in bovine erythrocytes and serum whereas the cervid
isolates were not. Post inocula tion calf sera showed strong
homologous reactions in the immunofluorescent antibody test,
although cross-reactions occurred as well. By transmission
electron microscopy, Babesia odocoilei was found to have a
feeding organelle not seen in the other isolates. The srRNA
gene sequences of B. odocoilei and the isolates from the elk
and caribou were identical. The cervid Babesia and B.
divergens sequences were aligned with those already available
from other Babesia and Theiletia spp. and phylogenetic trees
were inferred from the alignment. These trees indicated that
the cervid isolates were more closely related to B. divergens
than to any other Babesia. Trees inferred by distance
methods indicated that Babesia canis, classified as a "large"
babesia, was the next most closely related among the Babesia
spp. for which sequence data was available. The cervid
Babesia isolates and B. divergens were paired together within
the Babesia sensu stricto group in all of the phylogenetic
"Major subject: Veterinary Microbiology".