Table 3 Descriptive statistics for parity, days in milk (DIM), milk yield (kg/cow/day), milk protein content (%) and milk fat content (%) for D. viviparus positive and negative cows where test-day data was available [two records per cow if faecal examination and test-day data were available in summer and autumn (n = 1532); note that some cows changed infection status]
D. viviparus-positive cows | D. viviparus-negative cows | |||||
|---|---|---|---|---|---|---|
Mean | SD | Range | Mean | SD | Range | |
Parity | 1.3 | 0.7 | 1.0–4.0 | 2.9 | 1.8 | 1.0–11.0 |
DIM | 116.1 | 55.4 | 19.0–254.0 | 191.8 | 119.5 | 1.0–741.0 |
Milk yield | 19.9 | 5.5 | 9.4–34.4 | 21.4 | 7.1 | 2.4–47.6 |
Milk protein content | 3.4 | 0.3 | 2.7–4.0 | 3.5 | 0.4 | 2.4–6.3 |
Milk fat content | 4.1 | 0.5 | 3.3–5.6 | 4.2 | 0.7 | 2.0–7.2 |