On the occurrence of Eustrongylus gigas in a new host*
On the 9th of December, I received, through Dr. Vital Brazil, for examination, a recently shot female specimen of Galictis vittata,1 which had been killed on the wooded banks of the Rio Grande, two hours from São Paulo. The species is not at all common here in this region and therefore neither the hunter nor the bearer knew it. I myself had seen both living and stuffed specimens and considered this one to be full-grown.
It measured 36 cm from the snout to the root, and 50,5 cm to the tip of the tail, while the hairs extended another 5,5 cm beyond it.
As the animal was intended for taxidermic purposes, I had the innards removed; it was then seen that a shot, fired from quite near, had pierced both the belly and the back and had caused intense hemorrhage. Some white filaments were visible near the stomach and seemed to protrude from a piece of the intestine; on closer examination they proved to be the oviducts of an apparently very large worm. The eggs which were massed in the thicker parts, corresponding to the uterus, immediately reminded me of the well-known figures of Eustrongylus gigas, for which I had been looking for a long time in vain. Consequently, I examined the contents of the abdomen as thoroughly as the circumstance permitted.
I soon found, between the viscera, a number of fragments of tube-like formations which could be separated in two sets, according to their thickness. The extremities of the bodies were well-preserved and clearly showed the presence of two specimens, a male and a female. Although they had been badly torn by the grape-shot, I was able to reconstruct them almost entirely, so that approximate measurements could be taken. The following results were obtained:
A. Female: 8 fragments, the longest with the head, only slightly damaged, 36 cm; the others, altogether, 22 cm; total length 56 cm. Greatest breadth of the somewhat flattened specimen 8 mm; at the cephalic end, where more rounded and not collapsed, 5-6 mm. A large number of eggs were removed from the lapsed uterus for cultures.
B. Male: 3 fragments. Total length, 17 cm. Breadth throughout, approximately 4,5 mm. The terminal bursa copulatrix very distinct.
The fragments of both worms were of a dark, seal-red color decidedly conveying the impression of being inherent to them. The very marked lateral lines and the intestine (clearly visible by translucency) were pigmented black.
Examination of the abdominal organs showed the complete lack of one kidney; the worms, whose joint volume was considerably greater than that of the other kidney, had evidently disorganized it to the point that not even the much shrunken remnants of the burst sac could be recognized with certainty. I concluded that the worms had long been free in the abdominal cavity from the presence of numerous flat deposits on the surface of the liver. They were about the size of a lentil and similar to tubercles and they contained a large number of eggs of the worm.
The mode of life of Galicitis vittata, which is a very delicate and easily-tamed little creature, is probably similar to that of the weasel. Although nothing is known about the subject it seems likely that it occasionally eats fish, when it can catch them, for instance after floods.
São Paulo 11th December 1900.
Addendum
Through a remarkable coincidence, on the 29th of December, I again received specimens of Galictis vittata. There were 3 of them, an adult female and two almost grown young. They had been killed quite near to the Institute with sticks, by men working on the road.
The young ones did not contain any parasites; the adult animal, however, had also been infected with Eustrongylus gigas. The right kidney was well-preserved but the left one had been transformed into a thin-walled sac of about the same size, which was half-ossified. Inside it there were two tube-like formations which were unmistakably the integument of two specimens of E. gigas, the inner organs of which had disappeared through maceration. They measured 46 and 24 cm, but were not quite entire and so frail that I did not dare subject them to the manipulation necessary for examining them thoroughly. Well-preserved eggs were, however, found, a sign that at least one adult female had been present.
These animals were killed about one mile from the first finding-place and the next large course of water, but the finding of a Ligula larva in the adult female would seem to indicate that at some period it had lived beside water.
This new observation suggests that parasitism of Gallictis vittata by Eustrongylus gigas may occur fairly often.
São Paulo, 31st of December 1900.