養豚場へ侵入する野生哺乳類相についての事例報告

抄録

 We installed 10 motion-activated sensor cameras for 35 days within and around a pig farm facility in Ishikawa Prefecture, Japan, to investigate mammalian fauna that may transmit pathogens to pigs. The farm was surrounded by both electric fences and net fences in a double layer to prevent the invasion of wild boars, which can carry the swine fever virus. Five cameras were set in the forest area outside the fences and the remaining five were set inside the fences within the facility. A total of eight mammal species or groups of species were detected: wild boar, raccoon dogs, red foxes, Japanese hares, Japanese martens, domestic cats, rats, and bats. Large numbers of rats were seen within the facility. Wild boars were detected only in the forests outside the fences, and fences were thought to be effective in preventing wild boar invasion. Red foxes and raccoon dogs were photographed both inside and outside the fences, implying that they moved freely across the fence line. These medium-sized carnivora might have been attracted to the rats and livestock feed within the facility as food resources. These animals have the potential to transmit, indirectly, pathogenic viruses to pigs, such as swine fever, by carrying the virus on their bodies or defecating the virus within the facility. Thus, countermeasures are required to prevent the invasion of these wild animals.