Table 3 Selected clinical signs displayed up to 4 weeks prior to cull
From: Pruritus is a common feature in sheep infected with the BSE agent
Postmortem diagnosis | BSE POSITIVE | BSE NEGATIVE | P | ||
|---|---|---|---|---|---|
Clinical sign | Present | Absent | Present | Absent | * |
Behavioural abnormalities | |||||
Change in behaviour (dull or nervous) | 27 (61%) | 17 (39%) | 7 (10%) | 60 (90%) | +++ |
Bruxism when handled | 11 (27%) | 30 (73%) | 4 (6%) | 58 (94%) | + |
Bruxism when free during examination | 6 (15%) | 35 (85%) | 4 (6%) | 58 (94%) | ns |
Bruxism frequently during observations | 7 (23%) | 12 (40%) | 0 (0%) | 58 (89%) | +++ |
Bruxism occasionally during observations | 6 (20%) | Â | 0 (0%) | Â | +++ |
Bruxism during observations once | 5 (17%) | Â | 7 (11%) | Â | ns |
Sensory abnormalities (pruritus) | |||||
Rubbing or scratching frequently | 19 (63%) | 2 (7%) | 8 (12%) | 27 (43%) | +++ |
Rubbing or scratching occasionally | 7 (23%) | Â | 11 (17%) | Â | + |
Rubbing or scratching once | 2 (7%) | Â | 19 (28%) | Â | ns |
Nibbling frequently | 5 (17%) | 13 (43%) | 0 (0%) | 43 (68%) | + |
Nibbling occasionally | 7 (23%) | Â | 0 (0%) | Â | ++ |
Nibbling once | 5 (17%) | Â | 20 (32%) | Â | ns |
Positive scratch test | 35 (85%) | 6 (16%) | 1 (2%) | 61 (98%) | +++ |
Fleece changes | 19 (40%) | 28 (60%) | 10 (11%) | 77 (89%) | ++ |
Alopecia | 26 (55%) | 21 (45%) | 3 (3%) | 86 (97%) | +++ |
Skin lesions | 15 (32%) | 32 (68%) | 3 (3%) | 86 (97%) | +++ |
Self-induced scratch response | 27 (75%) | 9 (25%) | 3 (5%) | 62 (95%) | +++ |
Abnormalities in movement | |||||
Tremors | 22 (52%) | 20 (48%) | 4 (6%) | 64 (94%) | +++ |
Ataxia | 23 (49%) | 24 (51%) | 1 (1%) | 90 (99%) | +++ |
Physical changes | |||||
Weight loss >10% | 12 (25%) | 9 (22%) | 1 (2%) | 48 (70%) | +++ |
Weight loss 5–10% | 5 (13%) |  | 1 (2%) |  | + |
Weight loss < 5% | 15 (35%) | Â | 7 (10%) | Â | +++ |
Weight remained the same | 2 (5%) | Â | 11 (16%) | Â | ns |
Loss of body condition | 20 (57%) | 15 (43%) | 13 (34%) | 25 (66%) | ns |