Table 2.
The comparison of calf disease events, and the distribution of other variables in a clinical trial for the effect of single cow calving pens (treatment) vs. multiple cow calving pens (control) on the risk disease in Holstein heifer calves born on three Minnesota dairy farms in 2005.
| Variable | Group |
P value | |
|---|---|---|---|
| Treatment | Control | ||
| Number of calves enrolled (n) | 238 | 211 | – |
| Calf disease incidence | |||
| Diarrhea, n (%) | 78 (33) | 64 (30) | 0.58 |
| Pneumonia, n (%) | 13 (5) | 14 (7) | 0.60 |
| All cause morbidity, n (%) | 91(38) | 79 (37) | 0.86 |
| Mean ± SD number of days sick calves treated (d) | 2.3 ± 0.66 | 2.3 ± 0.71 | 0.81 |
| Assisted calving | |||
| Yes, n (%) | 92 (39) | 37 (18) | <0.001 |
| No, n (%) | 146 (61) | 174 (82) | – |
| Lactation | |||
| 1, n (%) | 92 (39) | 58 (27) | 0.012 |
| ≥2, n (%) | 146 (61) | 153 (73) | – |
| Birth season | |||
| Winter, n (%) | 102 (43) | 81 (38) | 0.34 |
| Summer, n (%) | 136 (57) | 130 (62) | – |
| Navel disinfection | |||
| Yes, n (%) | 206 (87) | 180 (85) | 0.7 |
| No, n (%) | 32 (13) | 31 (15) | – |
| Calf deaths within 90 d of study | |||
| Yes, n (%) | 4 (2) | 1 (1) | – |
| No, n (%) | 234 (98) | 210 (99) | 0.38a |
| Mean ± SD time-to-feeding first colostrum (h) | 6 ± 0.02 | 6 ± 0.2 | 0.31 |
| Mean ± SD volume of colostrum fed per calf (L) | 4 ± 0.02 | 4 ± 0.0 | 0.35 |
| Mean ± SD time-to-separation from dam (h) | 1.72 ± 0.05 | 1.85 ± 0.1 | 0.09 |
a
P value based on Fisher's exact test.