During a post-mortem examination of a cow in a suspected case of plant poisoning at Teven in February, 1952, a careful examination of the rumenal contents was carried out in the hope of finding some evidence of the presence of the suspected plant. Although the search was unsuccessful some unusual inhabitants of the rumen, in the form of nematodes ranging in length from 5-8 cms., were found. These were identified tentatively, from the size of the worms and the site in which they were found, as Gongylonema spp.; and this diagnosis was confirmed subsequently by Glenfield. Later the parasite was identified as Gongylonema pulchrum.
Since this parasite is regarded as being non-pathogenic, the chief reason for reporting its presence is to record the large number of worms present. This was estimated to be 200. Some were mixed with the rumenal contents, while others were firmly adherent to the mucous membrane and distributed over the whole of the rumen.
Monnig (1947) states that G. pulchrum occurs among others in the sheep, cattle, goat and pigs and less frequently in the horse. However. Seddon (1950) while noting its occurrence in cattle says that it has not been recorded from the pig in Australia.
It is usually found embedded in a zig-zag fashion in the submucosa of the oesophagus, although in ruminants it may occur also in the rumen.
According to Seddon (ibid) the life cycle requires an intermediate host and in the United States coprophagous beetles and roaches have been incriminated. The intermediate host in Australia has not been determined.
G. pulchrum in the rumen of cattle may be mistaken on occasions by stockowners for Haemonchus contortus.