[Ethmoid tumors in moose and roe deer].

Abstract

Ethmoid tumors are expansively-infiltratively growing tumors of carcinomatous or sarcomatous nature, deriving from the mucous membrane of the ethmoid bone. In Sweden, such tumors were found in 35 elks (Alces a. alces) and 4 roe deer (Capreolus capreolus) during the years 1947-1982, that means a frequency of about 1 and 0.1 per cent, respectively of the investigation material. However, in the free living elk and roe deer population, the frequency might be much lower. The tumors were malign, extensively melting the soft and hard tissues of the ethmoid region, breaking into the brain cavity, the forehead subcutaneous tissues, etc. Symptoms as suppurative or bloody discharge at the nose, external outline aberrations and disorders to be related to injuries of the central nervous system were observed. In the elk, ethmoid tumors were found only in female animals. In the beginning of this century, ethmoid tumors were found in a number of cattle and horses in Sweden and Norway. Multiple cases occurred in some herds indicating that the tumors were caused by an infectious agent. Since the year 1916, there seem to be no reports on the finding of ethmoid tumors in domestic animals in the Nordic countries. In 1960, however, such tumors were discovered in Indian cattle in Kerala in the south of India. Tumor tissue from the cattle was examined and a herpes-virus was found. Geographically, the distribution of the tumor cases in cattle and elk was very similar in Sweden indicating a possible mutual transmission. As the tumors obviously have disappeared from cattle but not from the elk, it seems likely that the elk might be the primary carrier of the ethmoid tumor. Ethmoid tumors have been observed for many years in Scandinavia but only rather recently they were discovered in India. It has been known for long that birds after contamination might be involved in the spread of virus diseases, provided the virus are reasonably resistant. In the actual case, the suspicion has mainly been directed at three bird species, viz. the blue throat (Luscinia svecica), the scarlet grosbeak (Erythrina erythrina) and the red-necked phalarope (Phalaropus lobatus). In spring and summer, these birds periodically reside in elk habitat where they might be contaminated. In the autumn, they may extend their migration to the southern parts of India.