A survey of endoparasites of the Red Kangaroo (Megaleia rufa (Desmarest)) has been carried out in three geographically distinct areas of south-eastern Australia.
During a period covering 22 months, 464 kangaroos of different sexes and ages were collected. Alimentary canals and tracheae of all of them and blood and organ smears from 333 were examined for parasites.
A list of endoparasites of the Red Kangaroo encountered during the study and of others reported earlier is given. This includes three species of blood protozoa, two species of coccidia (Eimeria spp.), two species of cestode and twenty-one species of nematodes.
The numbers of some nematode species are analysed in relation to season, sex of host and age of host as expressed by length of tibia.
Two different patterns of age susceptibility of the Red Kangaroo to nematodes are recorded and it is suggested that these may be dependent upon the presence or absence of direct contact of the parasite with host tissue.
Distribution of nematodes in the stomach of the Red Kangaroo has been studied. Different species were found to occupy separate niches within the stomach.
A statistical test aimed at showing the correlation between severity of infection with some nematodes and condition of host expressed by the ratio: body weight — stomach content/tibia length showed only a very weak negative correlation.
Alimentary canals of 100 sheep and thirty-five wild rabbits sampled simultaneously in the same area were found to be infected with only small numbers of worms.
No parasites injurious to domestic stock were found in the kangaroos examined.