in vitro culture and isoenzyme analysis of giardia lamblia

4.2 MATERIALS AND METHODS
4.2.1. Animal Sourcing and Care
C57BU6 inbred mice were recommended by Nash and Conrad (personal
communication) and these (eight weeks old) were obtained from the Biomedical
Resource Centre at the University of Durban Westville. In addition, an indigenous
species, readily available in our laboratory, Praomys (Mastomys) coucha (outbred)
was used. The mice were housed in cages cushioned with sawdust and the
temperature maintained at 25°C. A standard pellet diet and fresh water were
supplied to the animals ad lib. Soiled sawdust was replaced daily.
4.2.2 Preliminary Experiments:
To ensure that the animals were well suited for the in vivo experiments, some pilot
studies were necessary to:
~ eliminate any endogenous infections
~ *establish appropriate cyst dosages with which to effectively inoculate the mice
~ *establish the appropriate time to retrieve the trophozoites from infected mice
in order to ensure that maximum numbers of organisms are obtained.
*Although these have been published previously elsewhere, this type of work was being
done for the first time in SA and in our laboratory, furthermore the Mastomys strain used
here differs from those used by the other investigators.
4.2.2.1 Exclusion of Endogenous Giardia Infections
During the acclimatisation period, mouse faecal samples were collected on wetted
absorbent cotton-wool pads daily from each of the cages and were screened for
the presence of Giardia cysts using the formal-ether technique (2.2.2.1) for ten
days. The mice were deemed free of parasite infection if all faecal screens were
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