Boros István (szerk.): A Magyar Természettudományi Múzeum évkönyve 6. (Budapest 1955)

Szunyoghy, J.: A preliminary notice concerning the collectings of mammals, in connection with the researches on the disease nephroso-nephritis haemorrhagica in Hungary

The second collecting had been in the identical place, on the 12—19 October, 1954. The military camp had, at this time, been already uninhabited, with the exception of the guards. At the request of the military physicans, the center of the second collectings had again been the place of the infection and its immediate neighbourhood. Starting from this place, we collected in the heavy undergrowth and in the clear oak and beech woods bordering on the abandoned camp. At the same time, we examined also the buildings in the confines of the camp itself (store-rooms, kitchens, mess-halls, etc.). In one word, we have mainly trapped along the dense shrubbery and undergrowth crowding onto the very borders of the empty camp, — all favourite places of the small rodents and mammals. The second collecting had nothing new to add to the specific list of the results of the first ; the same species had again been caught. The result of the six nightly collectings are : 135 specimens of Apodemus flavicollis, 12 Mus spicilegus, 71 Clethrionomys glareolus, 1 Microtis arvalis, 4 Sor ex araneus, 4 Talpa europaea, = a total of 235 specimens. The second collecting shows again the dominancy of Apodemus flavicollis. with Clethrionomys in the second place as regards specimen numbers. Of the other species, Mus spicilegus, Microtus arvalis, Sorex araneus had a subordinate role, which is not surprising as their biotops do not correspond with the site of the military camp. On the base of the above results, a daily 15 per cent capture (the daily mean of all animals being 38, caught by the use of 250 traps) agrees with the lower limits of a medium animal density. (On a territory expressedly rich in animals, the daily amount of captured specimens may even reach 70—80 per cent.) This justifies the surmise, in our case, that small rodents can play the part of disease hosts even when present in small numbers only, — a conclusion contrary to former beliefs. We have listed, at that time purely on the ground of theoretical conceptions, that the disease-spreading animals will primarily belong to species with a high specimen numbers : first of all Apodemus, and then Clethrionomys. The suspicious role of Apodemus had been aggravated by the fact that they will, according to our informations, tolerate easily the presence and nearness of man and are willing to move into human shelters and so, naturally, into army tents too. The brains and kidneys of a part of the animals collected had been pathologically and histologically examined with the result that mainly Apodemus, but also Clethrionomys, specimens fall victims to the infectious and haemorrhagic inflammation of the kidneys, displaying also all characteristical alterations of the disease. In some of the specimens, the pathological processes of the kidneys had reached a stage when, by the opinion of the pathologists, the death of the animal was imminent. According to Soviet workers, nephroso-nephritis haemorrhagica infectiosa does not cause a lethal sickness in Mircotus fortis michnoi. This will suggest that this vole is infected since long by the virus of the disease, and its organism had adapted itself to it. By the above find of the pathologists, however, — that the death of the specimens would have set in because of the injuries sustained by the kidneys, — we have to assume that we are dealing with a very recent infection of a decidedly pathogenous effect for also the animals themselves. Until this theory is not justified by patho-histological examinations and, last