Volume 15, Number 5—May 2009
Research
A Case–Control Study on the Origin of Atypical Scrapie in Sheep, France
Alexandre Fediaevsky
, Eric Morignat, Christian Ducrot, and Didier Calavas
, Eric Morignat, Christian Ducrot, and Didier CalavasTable 4
Univariate analyses of feeding component variables during the specified period and conditional to C0 for atypical scrapie in sheep, France*
| Variable | Controls | Cases | Odds ratio | p value |
|---|---|---|---|---|
| Lambs fed milk replacers in C0 | ||||
| No | 68 | 42 | 0.5 | 0.02 |
| Yes | 157 | 53 | ||
| Corn silage in C0 | ||||
| No | 195 | 90 | 0.4 | 0.04 |
| Yes | 30 | 5 | ||
| Beet root in C0 | ||||
| No | 185 | 86 | 0.5 | 0.06 |
| Yes | 40 | 9 | ||
| Straw in C0 | ||||
| No | 77 | 23 | 1.6 | 0.08 |
| Yes | 148 | 72 | ||
| Oil cake in C0 | ||||
| No | 164 | 73 | 0.8 | 0.47 |
| Yes | 61 | 22 | ||
| Compound feed in C0 | ||||
| No | 78 | 28 | 1.3 | 0.37 |
| Yes | 147 | 67 | ||
| Grass silage in C0 | ||||
| No | 195 | 77 | 1.5 | 0.20 |
| Yes | 30 | 18 | ||
| Grain in C0 | ||||
| No | 45 | 18 | 1.1 | 0.83 |
| Yes | 180 | 77 | ||
| Molasses in C0 | ||||
| No | 212 | 88 | 1.3 | 0.59 |
| Yes | 13 | 7 | ||
| Vitamin and mineral supplements in C0 | ||||
| No | 102 | 48 | 0.8 | 0.40 |
| Yes | 123 | 47 | ||
| Salt licks (pure salt) during C0–C2006 | ||||
| No | 7 | 2 | 1.5 | 0.62 |
| Yes | 218 | 93 | ||
| Salt licks with minerals during C0–C2006 | ||||
| No | 46 | 28 | 0.6 | 0.08 |
| Yes | 179 | 67 | ||
| Other ruminants feed during C0–C0+2 | ||||
| No | 205 | 90 | 0.6 | 0.27 |
| Yes | 20 | 5 | ||
| Other ruminants minerals during C0–C0+2 | ||||
| No | 203 | 85 | 1.1 | 0.84 |
| Yes | 22 | 10 | ||
| Pig feed during C0–C0+2 | ||||
| No | 209 | 89 | 0.9 | 0.80 |
| Yes | 16 | 6 | ||
| Poultry feed during C0–C0+2 | ||||
| No | 193 | 80 | 1.1 | 0.71 |
| Yes | 32 | 15 | ||
*C0, birth cohort assuming that in each flock all animals born during the same birth campaign (defined from July 1 of year n – 1 to June 30 of year n) shared the same exposure; C2006, birth campaign 2006; C0–C0+2, period between C0 and the 2 subsequent reproduction campaigns.
