NORWAY CWD, SHEEP GRAZING, and Scrapie, What If?
Scrapie/reindeer investigation
10 Apr 1996 ProMed Tom Warren Univ. of Oslo 0316 Oslo Norway Tel. 472 285 4794 Telefax 472 285 4605
[Guess what -- inconvenient native people depende on reindeer. Note transmission of CWD to goats above -- webmaster]
'We have been investigating problems related to sheep grazing on alpine ranges which are used by wild reindeer. So far, the main problem seems to be between sheep owners and reindeer hunters, rather than between the animals themselves. It is important to mention that sheep/livestock grazing is in no way new in the area and summer grazing is abundant; winter habitat is the bottleneck for the reindeer. Private and public concern over the possible negative effects of sheep and sheep grazing on wild reindeer is not new; there has been competition for access to grazing resources/hunting for years. Since it is difficult on this particular range to argue that sheep "out-graze" reindeer, other possibilities such as disease/parasite transmission (from sheep to reindeer) have been advanced. When reports of scrapie among flocks of sheep which graze sympatrically with reindeer surfaced in 1994, concern for the reindeer was again voiced.
Last year, after a short review of existing literature, we concluded that there "seemed to be" a sufficient species barrier between sheep and reindeer, such that contraction of chronic wasting disease by the latter was unlikely. Inter-species transmission of prion diseases is apparently possible only through ingestion of infected tissue, especially brain/nerve tissue, which would not (likely) occur on the open range. This seems to be the concenses among reseachers working on CWD in the US. There is apparently no corelation between the occurence of CWD and sheep grazing. (Based on work in Colorado and Wyoming)
We found scrapie and the other prion disease so interesting that we wrote a popular account/description of scrapie and prions for the Norwegian Sheep and Goat Association's magazine. This article, written in Norwegian, appeared in February before the latest events in England. Since then, we have been inundated, locally, by requests for more information.
We still maintain that in an open range situation the chances of reindeer contracting CWD due to scrapie-infected sheep are, at best, remote. (Once scrapie is diagnosed, the flock is destroyed and no longer grazes on the open range. Uncertainty arises due to the long incubation times associated with prion diseases.) Our interest was, and remains, in the range management/ecolgy aspects of livestock/reindeer interactions; we are neither pathologists or veterinarians. We are currently following the debate here in Europe on BSE/CJD with great interest, however. Various theories circulate from week to week. Of greatest interest to us (and many others) is the question of the species barrier, and its role/function in extensive grazing situations.'
*** Spraker suggested an interesting explanation for the occurrence of CWD. The deer pens at the Foot Hills Campus were built some 30-40 years ago by a Dr. Bob Davis. At or abut that time, allegedly, some scrapie work was conducted at this site. When deer were introduced to the pens they occupied ground that had previously been occupied by sheep.
*** After a natural route of exposure, 100% of WTD were susceptible to scrapie.
TUESDAY, MARCH 28, 2017
*** Passage of scrapie to deer results in a new phenotype upon return passage to sheep ***
THURSDAY, AUGUST 10, 2017
NORWAY MAKES CHANGES TO NATIONAL CHRONIC WASTING DISEASE CWD TSE PRION RULES
SUNDAY, AUGUST 06, 2017
USA Chronic Wasting Disease CWD TSE Prion Emergency Response Plan Singeltary et al
Terry S. Singeltary Sr.
posted by Terry S. Singeltary Sr. at
11:12 AM
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