Western blot confirmation of scrapie infection.

<p>Examples of proteinase K treated samples from natural scrapie (lanes 1 & 3) and SSBP/1 (lanes 2 & 4). Loading: Lanes 1 and 2, equivalent to 20 mg starting brain wet weight; Lanes 3 and 4, equivalent to 6.67 mg starting brain wet weight.</p

Susceptible recipients challenged with SSBP/1 and development of scrapie in offspring.

<p>CD = caesarean derivation and hand rearing, NB = natural birth, reared by recipient ewe.</p>*<p>After SSBP/1 = number of days till death following challenge with SSBP/1.</p>**<p>(scr) – embryo donor later developed natural scrapie.</p>***<p>Where two progeny indicated per recipient, these developed <i>in utero</i> together and born as “twins”. Deaths are from scrapie (Death scrapie) or other causes (Death other) and given in days of age (d).</p>#<p>Incubation period in days (dy) when strain typed in tg 338 mice (SD).</p

Placental tissue and PrP^Sc.

<p>Immunostaining for PrP^Sc using BG4 antibody in placental tissue (cotyledon) from recipient ewe R46 (x 40).</p

Summary of results: numbers of scrapie cases in each genotype group following caesarean derivation or normal birth.

*<p>scr/n = number of scrapie cases/total number at risk of infection. CD = birth by caesarean section. NB = normal birth.</p

Central Nervous system pathology.

<p>Examples of vacuolation and immunostaining for PrP^Sc in brain tissue. A. Haematoxylin and Eosin (H&E) staining showing vacuolation in the dorsal motor vagus nucleus of L55 (VRQ/VRQ) had natural scrapie-like disease (x100). B. Strong immunostaining for PrP^Sc (diagnostic for natural scrapie) with BG4 antibody in the dorsal motor vagus nucleus of L55 (x40). C. Marginal immunostaining for PrP^Sc (diagnostic for SSBP/1) with BG4 in the dorsal motor vagus in the brain of L111 (VRQ/ARR) (x 100). D. Marginal immunostaining for PrP^Sc (diagnostic for SSBP/1) with BG4 in the dorsal motor vagus of L101 (VRQ/VRQ) (x100). E. Nil vacuolation (typical for SSBP/1) in an H&E section of the dorsal motor vagus in the brain of L101 (VRQ/VRQ) (x100). F. Marginal immunostaining for PrP^Sc (diagnostic for SSBP/1) in the brain of L106 (VRQ/VRQ) (x100).</p

Group 2: resistant recipients challenged with SSBP/1 scrapie and development of scrapie in offspring.

<p>CD = caesarean derivation and hand rearing, NB = natural birth, reared by recipient ewe.</p>*<p>(scr) – embryo donor later developed natural scrapie.</p>**<p>Where two progeny indicated per recipient, these developed <i>in utero</i> together and born as “twins”. Deaths are from scrapie (Death scrapie) or other causes (Death other) and given in days of age (d).</p

Summary of results, numbers of scrapie cases in each genotype group at risk from scrapie.

*<p>scr/n = number of scrapie cases/total number at risk of infection.</p

Group 1: unchallenged recipients and development of scrapie in offspring.

<p>CD = caesarean derivation and hand rearing, NB = natural birth, reared by recipient ewe.</p>*<p>(scr) – embryo donor later developed natural scrapie</p>**<p>Where two progeny indicated per recipient, these developed <i>in utero</i> together and born as “twins”. Deaths are from scrapie (Death scrapie) or other causes (Death other) and given in days of age (d).</p

Definitions of epidemiological parameters used in the study.

<p>Definitions of epidemiological parameters used in the study.</p

Frequency of polymorphisms at codons 112, 141 and 241 of the <i>PrP</i> gene in confirmed scrapie cases.

<p>(Amino acids are: methionine (M); threonine (T); leucine (L); phenylalanine (F); proline (P); serine (S); UNK indicates the number of cases for which information on the polymorphism was not available).</p