SUMMARYTrophozoites o f th e Giardi a muri s grou p fro m hamsters , domesti c rat s an d mice an d o f th e Giardi a duodenali s grou p fro m hamster s an d domesti c rat s wer e examined b y transmissio n electro n microscopy . Th e basi c ultrastructur e o f th e trophozoites wa s similar. Difference s wer e show n in th e morphology o f th e ventrolateral flang e of th e trophozoite s o f Giardi a muris an d Giardia duodenalis groups. Marginal plate s are less developed in the specie s of th e Giardia duodenalis group. I n this group , th e dista l extremit y o f th e latera l flang e i s shor t an d thic k an d th e marginal plat e doe s no t penetrat e int o th e dista l extremit y o f th e flange . I n th e Giardia muris group, th e ventro-lateral flang e is well developed and narrow an d th e marginal plate penetrate s th e distal extremity o f th e flange. The osmiophilic lamella , which accompanie s th e dorsa l surfac e o f th e margina l plat e i s see n onl y i n th e Giardia muri s group .KEY WORDS : Giardi a muris; Giardi a duodenalis; Trophozoite, Ultrastructure .
INTRODUCTIONBased o n th e media n bod y morpholog y and th e trophozoite' s siz e an d shap e on e ca n differentiate Giardi a muri s an d Giardi a duodenalis b y ligh t microscopy 4 . Th e dat a i n the literatur e abou t suc h differentiatio n b y electron microscop y ar e scarce. NEMANIC et. al.12 wer e unabl e t o sho w difference s betwee n trophozoites o f Giardi a muri s fro m mic e an d those of Giardi a lamblia fro m man.Taking i n accoun t thes e result s an d since the morpholog y o f Giardi a from hamster s an d domestic rat s ha d no t bee n describe d yet , w e decided t o stud y comparativel y th e ultrastructure o f Giardi a muri s an d Giardi a duodenalis trophozoite s foun d i n hamsters , domestic rat s and mice.
MATERIAL AND METHOD SGiardia specie s fro m naturall y infecte d animals wer e previousl y identifie d b y ligh t microscopy. Smear s o f faece s or mucos a wer e fixed wit h Schaudinn' s solutio n an d staine d with Heidenhain' s haematoxylin . Th e species of Giardi a wer e identifie d b y morphologica l features an d trophozoit e lengt h an d widt h measurements, at 1.00 0 x magnification .Trophozoites o f th e Giardi a muri s grou p from hamsters , domesti c rat s (Rattu s rattu s rattus) an d mic e and Giardia duodenalis grou p from hamster s an d domesti c rat s wer e used . Fragments o f th e host' s mucos a were fixe d i n 2.5% glutaraldehyd e buffere d a t p H 7. 3 wit h 0.1M phosphat e buffer, post-fixed i n 1 % osmic tetroxide i n th e sam e buffer an d embedde d i n Araldite. Th e ultrathi n section s wer e staine d with urany l acetat e an d lea d citrat e an d examined wit h a n E M 30 1 Philip s electro n microscope.
RESULTSThe basi c ultrastructur e o f th e trophozoites o f Giardi a uiuri s grou p fro m hamsters , domestic rat N an d mic e and Giardia duodenalis group fro m hamster s and domestic rat s i s similar. Th e trophozoite s hav e a microtubuia r adhesive disk surrounded b y a n adj...
