in vitro culture and isoenzyme analysis of giardia lamblia

Table 4.4. Summary of the inoculations attempted in Mastomys and C57BU6
mice with resultant findings.
C57BL\6 39(-1)* 15/(61%)
Mastomys 14(-4)* 5/(50%)
Total t53 20
* Lost through cannibalism after inoculation. This was more common in Mastomys (29%)
compared with the C57BL\6 (3%). Approximately 61% of C57BL\6 resisted infection while 50% of
the Mastomys were not infected.
tOf the 53 inoculation trials, 47 were interpretable, as 5 litters were lost through
canibalism and 1 litter was heavily infested with Hexamita muris (synonym.
Spironuc/eus muris, a common rodent parasite). Twenty of the 47 inoculated
litters (43%) became infected while 26 (55%) failed to harbour trophozoites (22 in
C57BU6 and 4 in Mastomys), despite replicate attempts in 12 batches (Appendix
5). In two instances, Mastomys mice were co-infected with numerous flagellates
(Hexamita muris) and the Giardia trophozoites subsequently died in vitro. In one
litter the numbers of the contaminating organisms were so overwhelming that it
was not possible to confirm the presence or absence of the Giardia trophozoites.
In addition to the mouse inoculations, cyst samples were concurrently processed
for in vitro excystation. A comparison between the two excystation methods was
subsequently undertaken. Different outcomes were observed for each of them. It
was found that in some instances cysts would excyst by the one method but not
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