FAQ: During the quarantine period, what were the beavers tested for and what were the results?

All beavers arriving from Norway firstly undertook a one month quarantine period at a Norwegian holding facility, associated with Telemark University College. On arrival in Britain they were then subjected to the statutory rabies quarantine of 6 months. This is a DEFRA requirement for all mammals entering the UK, unless under special circumstances. During quarantine the beavers were monitored regularly. Blood and faecal samples were collected for veterinary testing and prior to release all beavers were specifically tested for Salmonella, Campylobacter, Yersinia, Clostridium, Leptospirosis and Tularemia. Faecal samples were tested for general parasites while blood samples were obtained to assess blood biochemistry, haematology and white blood cell counts.

Blood results were compared to reference ranges for both Eurasian and North American beaver species. Any beavers displaying results greatly outside the normal ranges were not released until further veterinary investigations were carried out and those individuals have been retested. High white blood cell counts can indicate infections, which would then have been treated before any release.

Faecal samples submitted for parasitology have shown that beavers do naturally carry internal nematode worms and some animals have tested positive for the beaver fluke Stichorchis subtriquetrus. This fluke or trematode is a parasite that occurs naturally in beavers and is specific to the genus Castor.

Prior to release all beavers were subjected to a full clinical examination by The Royal Zoological Society of Scotland and independent veterinary surgeons to assess ear, eye, skin and body condition as well as dental and skeletal abnormalities. Any beavers with infections, injuries, heavy parasite loads or those who tested positive for any of the veterinary tests stated were not passed fit for release.