Table 1.
TSE infectivity detected within bovine heads and in surrounding soil
| Clay | Sand | ||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Year | 1 | 2 | 3 | 4 | 5 | SC | 1 | 2 | 3 | 4 | 5 | SC | |||||||||||||
| N | IP | N | IP | N | IP | N | IP | N | IP | N | IP | N | IP | N | IP | N | IP | N | IP | N | IP | N | IP | ||
| Samples taken from within the heads | |||||||||||||||||||||||||
| In head | A | 4/4 | 149 | 4/4 | 165 | 3/4 | 201 | 4/4 | 167 | 4/4 | 173 | 1/4 | 181 | 0/4 | 4/4 | 137 | 2/4 | 237 | 4/4 | 180 | |||||
| B | 4/4 | 155 | 4/4 | 134 | 2/4 | 193 | 2/4 | 174 | 1/4 | 175 | 4/4 | 153 | 4/4 | 130 | 4/4 | 130 | 4/4 | 149 | 4/4 | 173 | |||||
| C | 4/4 | 162 | 4/4 | 151 | 4/4 | 165 | 4/4 | 184 | 1/4 | 328 | 4/4 | 158 | 4/4 | 130 | 3/4 | 180 | 4/4 | 179 | 4/4 | 168 | |||||
| D | 3/4 | 222 | 3/3 | 144 | 4/4 | 214 | 4/4 | 207 | 4/4 | 205 | 4/4 | 161 | 4/4 | 130 | 0/4 | 4/4 | 202 | 4/4 | 165 | ||||||
| E | 2/4 | 186 | 2/4 | 185 | 0/4 | 4/4 | 198 | 4/4 | 186 | 4/4 | 143 | 3/4 | 268 | 3/4 | 156 | 4/4 | 151 | 3/4 | 201 | ||||||
| F | 2/4 | 234 | 4/4 | 140 | 1/4 | 315 | 2/4 | 205 | 3/4 | 226 | 3/3 | 160 | 2/4 | 235 | 4/4 | 152 | 4/4 | 153 | 4/4 | 159 | |||||
| Clay | Sand | ||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Depth (cm) | N | IP | N | IP | N | IP | N | IP | N | IP | N | IP | N | IP | N | IP | N | IP | N | IP | N | IP | N | IP | |
| Samples taken from the soil around the heads | |||||||||||||||||||||||||
| N | 40 | 0/3 | 0/4 | ||||||||||||||||||||||
| 50 | 0/4 | 0/4 | 0/4 | 0/4 | 1/4 | 210 | 0/4 | 0/1 | 0/4 | 0/4 | 0/4 | ||||||||||||||
| 60 | 0/4 | 0/4 | 1/4 | 251 | 4/4 | 237 | 3/4 | 296 | 0/4 | 1/4 | 359 | 0/6 | 0/4 | 0/4 | 0/4 | 0/4 | |||||||||
| 70 | 0/4 | 0/4 | 3/4 | 237 | 0/4 | 0/4 | 0/4 | 0/5 | 0/4 | 1/4 | 236 | 0/4 | |||||||||||||
| 80 | 0/4 | 0/4 | |||||||||||||||||||||||
| E | 40 | 0/4 | |||||||||||||||||||||||
| 50 | 0/3 | 0/4 | 1/4 | H | 0/4 | 0/4 | 0/4 | 0/5 | 0/4 | 0/4 | 0/4 | ||||||||||||||
| 60 | 0/4 | 1/4 | 307 | 3/4 | H | 2/2 | 181 | 0/4 | 0/4 | 0/4 | 0/4 | 0/4 | 0/4 | 0/4 | 0/4 | ||||||||||
| 70 | 0/3 | 0/4 | 3/4 | 239 | 4/4 | 188 | 0/4 | 0/7 | 1/3 | H | 0/4 | 0/4 | 0/4 | ||||||||||||
| 80 | 0/4 | 1/4 | 295 | ||||||||||||||||||||||
| S | 40 | 0/4 | 0/4 | ||||||||||||||||||||||
| 50 | 0/3 | 0/8 | 0/4 | 0/4 | 0/4 | 0/4 | 0/4 | 0/4 | 0/4 | 0/4 | |||||||||||||||
| 60 | 0/4 | 1/4 | 230 | 0/4 | 1/4 | 355 | 0/4 | 0/4 | 1/3 | 218 | 0/6 | 0/4 | 0/4 | 0/4 | 0/4 | ||||||||||
| 70 | 0/4 | 0/4 | 2/4 | 223 | 1/4 | 321 | 0/4 | 0/4 | 0/4 | 0/4 | 0/4 | 0/4 | |||||||||||||
| 80 | 0/4 | 0/4 | |||||||||||||||||||||||
| W | 40 | 0/4 | 0/4 | ||||||||||||||||||||||
| 50 | 0/3 | 0/4 | 0/4 | 4/4 | 283 | 0/4 | 0/4 | 0/4 | 0/4 | 0/4 | 1/4 | 295 | |||||||||||||
| 60 | 1/3 | 183 | 0/4 | 0/4 | 4/4 | 129 | 0/4 | 0/4 | 1/4 | 317 | 0/4 | 0/4 | 0/4 | 0/4 | 0/4 | ||||||||||
| 70 | 0/3 | 0/4 | 0/4 | 2/4 | 254 | 2/4 | 172 | 0/3 | 0/4 | 0/4 | 0/4 | 0/4 | |||||||||||||
| 80 | 0/4 | 0/4 | |||||||||||||||||||||||
| Cen | 60 | 2/3 | 257 | ND | 4/4 | 267 | 4/4 | 169 | 2/3 | 252 | 0/4 | 0/4 | 0/4 | 0/4 | 0/4 | 1/4 | 204 | 0/4 | |||||||
| 70 | 1/4 | 218 | 1/4 | H | 4/4 | 190 | 0/4 | 0/4 | 0/4 | 0/4 | 0/4 | 0/4 | 0/4 | 1/4 | 267 | 0/4 | |||||||||
| 80 | 1/4 | 239 | 0/4 | 2/4 | 174 | 3/4 | 244 | 1/4 | 203 | 0/3 | 0/4 | 1/4 | H | 0/4 | 3/4 | 255 | |||||||||
| 100 | 0/4 | 2/4 | 288 | ||||||||||||||||||||||
Six samples from the skull cavity (A-F) were analysed along with soil samples taken from a central core above and below the head (Cen) and from cores 25 cm from the central core in N, E, S and W directions (soil depths of sample collection are also indicated). Samples were tested for TSE infectivity in mice. The number of TSE-positive mice per group/total number injected and surviving for assessment are shown (column N), with the average incubation period in days postinfection of each TSE-positive group (column IP). Those that were diagnosed TSE positive only from histological examination of the mouse brains after culling are indicated (H). Samples with any sign of infectivity are in bold. Soil controls (SC) were taken each year from lysimeters filled with sand or clay without cattle heads at the depths indicated