Table I.
Study population used to determine the prevalence of Toxoplasma gondii in Ontario by year of sampling
| Year of sampling
|
|||
|---|---|---|---|
| 2001 | 2003 | 2004 | |
| Animals tested | 2848 | 1600 | 1600 |
| Animals apparently positive | 40 | 1 | 4 |
| Farms tested | 95 | 80 | 80 |
| Farms apparently positive | 13 | 1 | 3 |
| Animals tested per farm | 30 | 20 | 20 |
| Type of farm — sampling site (%) | |||
| Farrow-to-finish (%) | 60 | 61.3 | 71.3 |
| Finishers only (%) | 33.7 | 32.5 | 26.3 |
| Nursery and finishers (%) | 6.3 | 6.3 | — |
| Farrowing and GF | — | — | 2.5 |
| Integration level (%) | |||
| Company (%) | 18.9 | 16.3 | 16.3 |
| Family loops (%) | 11.6 | 12.5 | 13.8 |
| Independent (%) | 69.5 | 71.3 | 70 |
| Number of sites (%) | |||
| 1 site (%) | 52.6 | 52.5 | 50 |
| 2 sites (%) | 25.3 | 21.25 | 25 |
| 3 and more sites (%) | 22.1 | 26.25 | 25 |
| Number of finisher pigs on-site (Mean) | 1232 | 1190 | 1050 |
| Number of finisher pigs on-site (s ) | 1150 | 1109 | 821 |
| Proportion of farms with cats (%) | 56.8 | 36.3 | 10.0 |
fis = standard deviation; GF — growing-finishing phase.