TABLE 3.
Prevalence of brucellosis according to animal-related risk factors.
| Brucellosis-positive |
Brucellosis-negative |
p | |||
|---|---|---|---|---|---|
| Number | % (Proportion) | Number | % (Proportion) | ||
| Breed | - | - | - | - | 0.001 |
| Indigenous | 40 | 13.8 | 250 | 86.2 | - |
| Cross-breed | 74 | 23.6 | 240 | 76.4 | - |
| Sex | - | - | - | - | 0.460 |
| Female animals | 108 | 19.0 | 460 | 81.0 | - |
| Male animals | 6 | 16.7 | 30 | 83.3 | - |
| Abortion | - | - | - | - | 0.000 |
| History of abortion | 94 | 17.0 | 458 | 83.0 | - |
| No history of abortion | 20 | 38.5 | 32 | 61.5 | - |
| Retained placenta | - | - | - | - | 1.470 |
| History of retained placenta | 108 | 36.0 | 192 | 64.0 | - |
| No history of retained placenta | 6 | 2.0 | 298 | 98.0 | - |
| Parity | - | - | - | - | |
| 0 (heifers) | 20 | 12.8 | 136 | 87.2 | a |
| 1st | 14 | 14.3 | 86 | 87.8 | a |
| 2nd | 18 | 18.6 | 77 | 79.4 | a |
| 3rd | 18 | 27.7 | 47 | 72.3 | a |
| 4th | 26 | 32.5 | 54 | 67.5 | a |
| 5th | 12 | 16.7 | 60 | 83.3 | a |
| Overall | 108 | 19.0 | 460 | 81.0 | - |
| Reproductive category | |||||
| Cows | 88 | 21.4 | 324 | 78.6 | a |
| Bulls | 6 | 16.7 | 30 | 83.3 | a |
| Heifers | 20 | 12.8 | 136 | 87.2 | a |
| Overall | 114 | 18.9 | 490 | 81.1 | a |
| Grazing system | - | - | - | - | 0.28 |
| Extensive grazing | 114 | 19.1 | 484 | 80.9 | - |
| Intensive grazing | 0 | 0.0 | 6 | 100.0 | |
| Herd size | |||||
| 1–9 cattle | 0 | 0.0 | 6 | 100.0 | a |
| 10–39 cattle | 58 | 14.9 | 332 | 85.1 | a |
| 40–70 cattle | 56 | 26.9 | 152 | 73.1 | a |
Confidence intervals and p-values are calculated in Table 4.
a
, Odds ratios.