Table 3.
Variable | N | % | Minimum | 25th percentile | Median | 75th percentile | Maximum |
---|---|---|---|---|---|---|---|
Lactation number | |||||||
1 | 33 | 18.6 | – | – | – | – | – |
2 | 44 | 24.9 | – | – | – | – | – |
3 | 100 | 56.5 | – | – | – | – | – |
Stage of lactation at sample collection | |||||||
Early (0–100 days in milk) | 92 | 52.0 | – | – | – | – | – |
Mid (101–200 days in milk) | 40 | 22.6 | – | – | – | – | – |
Late (201+ days in milk) | 45 | 25.4 | – | – | – | – | – |
Lactating herd size | – | – | 41 | 50 | 58 | 83 | 199 |
Mean days in milka | – | – | 146 | 167 | 174 | 184 | 215 |
Mean 24 h milk production (kg)a | – | – | 26 | 29 | 31 | 32 | 40 |
Mean somatic cell count (1,000 cells/mL)a | – | – | 107 | 161 | 183 | 266 | 327 |
aWithin herd averages were calculated using data collected by the regional Dairy Herd Improvement agency over the course of the study period (2007 and 2008).