Scrapie is a deadly, degenerative and transmissible disease that affects the central nervous system of sheep and goats.
Scrapie has been known since the 18th century. This disease has been present in sheep and goats for centuries and has been observed worldwide, but especially in Western Europe and North America. In French the disease is called Tremblante and in German Traberkrankheit.
The name Scrapie is derived from one of the symptoms. Due to severe itching, sick animals scrape their skin against fences or other fixed objects. Other symptoms are a dry coat and skin, and severe weight loss. Movement disorders can also occur. However, these are not as pronounced as with BSE in cattle; usually only one animal of the herd is affected.
Long incubation time
Scrapie has an incubation period of more than two years. As a result, the disease symptoms are only seen in adult animals. In non-susceptible animals, the pathogen has virtually no chance of causing disease symptoms during their relatively short lives.
There are classical forms and atypical forms of scrapie. Scrapie, like BSE, is a transmissible spongiform encephalopathy (TSE) or prion disease. Prion diseases are very unusual; unlike bacterial, viral or parasitic infections, prion diseases are caused by a protein that is normally present in the host. This protein is known as a prion protein or simply PrP.
Spreading the infection
Scrapie is an infectious disease. The nature of the agent (the prion) that causes Scrapie is not fully understood, and the mode of transmission is not entirely clear. It has been established that the Scrapie agent can survive several years in the environment, that it is relatively resistant to disinfectants and that host genetic (hereditary) factors mainly determine the susceptibility to the disease. In sheep, the assumption is that an important route of horizontal and vertical transmission is via the placental material (afterbirth) of infected ewes during lambing.
Homogenous PrPres pattern in experimentally BSE-infected goat brains of different genotypes allows differentiation from natural goat scrapie types
Improvement of goat TSE discriminative diagnosis and susceptibility based assessment of BSE infectivity in goat milk and meatLelystad : Central Veterinary Institute of Wageningen UR (CVI) - p.
Medulla oblongata transcriptome changes during presymptomatic natural scrapie and their associaition with prion-related lesions.BMC Genomics 13 (2012). - ISSN 1471-2164
Sharp decline in scrapie prevalence in the Netherlands after breeding for resistance: Are we close to achieving eradication?
Modelling classical scrapie control through selective breeding in the ovine Sarda breed in Italy
The identification of disease-induced biomarkers in the plasma of scrapie infected sheep
Ovine field ch 1641 like scrapie cases do differ from classical scrapie and BSE- Western blotting studies on PrPes
Transcriptome changes of ovine medulla oblongata during presymptomatical natural scrapie and their association with prion-related lesions
Sharp decline in scrapie prevalence in the Netherlands after breeding for resistance: Are we close to achieving eradication?In: Prion 6, Amsterdam, The Netherlands, 10-12 May 2012. - : Landes Bioscience - p. 72 - 73.
Eradicating BSE in goatsInternational Innovation (2012). - ISSN 2041-4552 - p. 100 - 102.