NR AECB
AU Foote,W.C.; Clark,W.W.; Maciulis,A.; Call,J.W.; Hourrigan,J.; Evans,R.C.; Marshall,M.R.; de Camp,M.
TI Prevention of scrapie transmission in sheep, using embryo transfer
QU American Journal of Veterinary Research 1993 Nov; 54(11): 1863-8
PT journal article
AB Reciprocal embryo transfers were made between scrapie-inoculated and scrapie-free sheep (Cheviot and Suffolk breeds) to measure scrapie transmission via the embryo (using offspring from embryos of scrapie-inoculated donors and scrapie-free recipients) and via the uterus (using offspring from embryos of scrapie-free donors and scrapie-inoculated recipients taken by cesarean section). Two control groups of offspring, 1 from scrapie-free parents (negative) and 1 from scrapie-inoculated parents (positive), also were included. All sheep were observed for clinical signs of scrapie until death or for a minimum of 60 months. Final diagnosis was made on the basis of histopathologic findings or results of mouse inoculation and/or proteinase-K-resistant protein analysis. Thirty to 61% of the scrapie-inoculated donor/recipient sheep within groups developed scrapie within 8 to 44 months after inoculation. None of the scrapie-free donor/recipients, including those gestating embryos from scrapie-inoculated donors, developed scrapie. Also, none of the offspring observed to > or = 24 months of age from reciprocal cross, via embryo (0/67), or via the uterus (0/25), or from the negative-control group (0/33) developed scrapie. Fifty-six of the offspring via embryo, 19 of these via the uterus, and 31 negative controls survived to > or = 60 months of age. Of the 21 sheep in the positive-control group, 2 (9.5%) developed scrapie, 1 at 31 months of age and 1 at 42 months of age. In the Cheviot offspring, the percentage of sheep carrying the short incubation allele ranged from 24 to 44% and the percentage in the Suffolk offspring ranged from 61 to 83%.(ABSTRACT TRUNCATED AT 250 WORDS)
IN Scrapie-infizierten und nicht infizierten Schafen wurden per Kaiserschnitt Embryonen entnommen. Die Embryonen der infizierten Schafe wurden nicht infizierten Schafen eingepflanzt, während infizierten Schafen die Embryonen von nicht infizierten Schafen eingepflanzt wurden. Dummerweise erkrankten längst nicht alle infizierten Mutterschafe und selbst in der Positivkontrollgruppe von 20 ohne Embryotransfer geborenen Lämmern infizierter Mütter erkrankten nur 2 an Scrapie. Von den 67 von nicht infizierten Müttern geborenen und den 25 von infizierten Müttern geborenen Embryotransfer-Schafen, sowie von 33 Neagativkontrollen starb keines an Scrapie. Leider starben je 2 der 67 bzw. 33 und sogar 6 der 25 Schafe vorzeitig.
MH Animal; Embryo/microbiology; Embryo Transfer; Female; Maternal-Fetal Exchange; Pregnancy; Prions/isolation & purification; Scrapie/microbiology/*prevention & control/*transmission; Sheep; Support, Non-U.S. Gov't; Support, U.S. Gov't, Non-P.H.S.; Time Factors; Uterus/microbiology
AD Warren C. Foote, Alma Maciulis, Jay W. Call, R. Cole Evans, Animal, Dairy and Veterinary Sciences Department, Utah State University, Logan 84322-4815, USA; Wilber Clark, Margarete de Camp, The USDA, Animal and Plant Health Inspection Service, Veterinary Services, Scrapie Investigation Center, Mission, TX 78572, USA; James Hourrigan, The USDA, Animal and Plant Health Inspection Service, Veterinary Services, Hyattsville, MD 20782, USA; Michael R. Marshall, Utah Department of Agriculture, Salt Lake City, UT 84116, USA
SP englisch
PO USA
ZF kritische Zusammenfassung von Roland Heynkes