Table 4.
Cox regression model output on the relation between serum protein fractions determined by routine electrophoresis at arrival on time to diagnosis of bovine respiratory disease in a cohort of 150 rosé veal calves originating from 3 different batches.
| Variable | Category | Calves (n) | BRD positive (%) | HR | 95% CI | P-value |
|---|---|---|---|---|---|---|
| Arrival batch | NL1 | 26 | 61.5 | ref. | ||
| NL2 | 27 | 74.1 | 0.9 | 0.5–1.6 | 0.75 | |
| GER | 97 | 57.7 | 1.3 | 0.7–2.5 | 0.44 | |
| Immunoglobulin (Ig) (g/L) | Positive | 111 | 55.9 | ref. | ||
| Negative | 39 | 76.9 | 1.9 | 1.2–3.0 | <0.05 |
HR = hazard ratio; ref. = referent category; NL = the Netherlands; GER = Germany; BRD = bovine respiratory disease.