Variable |
| n | Coefficient | Std. Error | t | P > |t| | 95% CI | |
Age at conception |
| 101 | 2.26 | 0.34 | 6.59 | <0.0001 | 1.58 | 2.94 |
Enterprise type | Baseline | 40 | Holstein | |||||
| Holstein-Friesian | 29 | 57.44 | 43.14 | 1.10 | 0.274 | −3.26 | 133.13 |
| Holstein x | 13 | 88.11 | 59.52 | 1.48 | 0.142 | −30.12 | 206.34 |
| Friesian x | 4 | −37.67 | 105.51 | −0.36 | 0.722 | −247.26 | 171.71 |
| Other purebreds | 9 | 84.23 | 71.73 | 1.17 | 0.243 | −58.26 | 226.71 |
| Jersey | 6 | −30.87 | 78.73 | −0.39 | 0.696 | −187.26 | 125.51 |
Calving pattern | Baseline | 73 | All year round | |||||
| Autumn | 14 | −136.27 | 56.62 | −2.41 | 0.018 | −248.74 | −23.81 |
| Multi block | 10 | −39.30 | 61.76 | −0.64 | 0.526 | −161.98 | 83.37 |
| Spring | 5 | −184.46 | 94.24 | −1.96 | 0.053 | −371.66 | 2.73 |