Table 4.
Effect of age (years) and the total score (points) of body conformation traits on the risk of clinical mastitis and lameness in Chinese holstein cows
| Diseases | Effect | Level | B | SE | Wald χ2 | df | OR value | 95% confidence interval | P value | |
|---|---|---|---|---|---|---|---|---|---|---|
| Lower limit | Upper limit | |||||||||
| Mastitis | Age | 3 vs. 2 | 1.13 | 0.26 | 18.51 | 1 | 3.56 | 2.05 | 6.17 | < 0.001 |
| 4 vs. 2 | 1.38 | 0.27 | 25.85 | 1 | 4.34 | 2.47 | 7.64 | < 0.001 | ||
| 5 vs. 2 | 2.03 | 0.81 | 6.36 | 1 | 8.00 | 1.61 | 39.80 | 0.012 | ||
| TS | 80–85 vs. 76–79 | -0.71 | 0.17 | 17.69 | 1 | 0.49 | 0.35 | 0.68 | < 0.001 | |
| lameness | Age | 4 vs. 3 | 0.19 | 0.52 | 0.13 | 1 | 1.26 | 0.44 | 3.62 | 0.665 |
| TS | 80–85 vs. 76–79 | -0.62 | 1.05 | 0.34 | 1 | 0.86 | 0.31 | 2.39 | 0.766 | |
B: unstandardized regression weight; SE: standard error for B; Wald χ2: the test statistic for the individual predictor variable; df: degrees of freedom. For mastitis, the 2 years was the base class, while 76–79 TS (points) of the body conformation traits points for age. For lameness, the 3 years and 76–79 points were the base classes of the age and TS of the body conformation traits