The Influence of Alpine Farming on the Virome of Swiss Cattle, Goats and Sheep

Vet. Med. Master Thesis by Sara Marti

Nearly a third of the Swiss cattle population and even a higher percentage of sheep spend the summer on alps. However, alpine farming can harbor infectiological hazards, since animals from different farms and even different species, including wild animals, get in contact with each other. Furthermore, vectors such as biting midges, ticks and mosquitos, which due to global warming extend their habitats to higher altitudes, can transmit pathogenic viruses to native livestock, e.g. bluetongue virus or Schmallenberg virus.

The aim of this master project is to identify the viruses circulating in Swiss livestock (cattle, sheep and goats), wild animals (e.g. deer, roe deer, chamois) as well as potential vectors on alpine pastures. For this purpose, blood samples of cattle, sheep and goats of one farm are collected before and after the “alping” season. On the alps, vector traps are installed in order to collect arthropods like biting midges, mosquitoes and ticks. Blood, spleen, liver and skin samples of hunted game are collected by the indigenous hunters. The samples are tested for several viral infections either directly via (RT-)PCR methods or indirectly via enzyme-linked immunosorbent assays (ELISAs), e.g. bluetongue virus (BTV), Schmallenberg virus (SBV), Bovine viral diarrhea virus (BVDV), Bovine herpesvirus 2 (BoHV-2), Tick-borne encephalitis virus (TBEV) etc.