Table 4.
Effect of weaning age on blood-biochemical parameters and immune biomarkers of calves
| Item | Control group | Group 4 wk | Group 6 wk | Group 8 wk | Group 10 wk | SEM | p-value | ||
|---|---|---|---|---|---|---|---|---|---|
|
| |||||||||
| Tr | Age | Tr×Age | |||||||
| Glucose (mmol/L) | |||||||||
| 10 wk (70 d) | 6.61a | 5.01b | 5.31b | 5.10b | 5.78b | 0.132 | 0.002 | 0.128 | 0.032 |
| 13 wk (91 d) | 7.26a | 5.57b | 5.59b | 5.11b | 5.89b | 0.101 | 0.023 | - | - |
| 22 wk (150 d) | 6.11a | 5.65b | 5.41b | 5.74b | 5.66b | 0.294 | 0.041 | - | - |
| Urea nitrogen (mmol/L) | |||||||||
| 10 wk (70 d) | 5.76a | 4.11b | 4.24b | 3.94b | 5.47a | 0.447 | <0.0001 | 0.540 | 0.128 |
| 13 wk (91 d) | 5.67a | 4.19b | 4.34b | 4.41b | 4.51b | 0.552 | 0.029 | - | - |
| 22 wk (150 d) | 5.58a | 4.20b | 4.27b | 4.11b | 4.55b | 0.351 | 0.006 | - | - |
| Total protein (g/L) | |||||||||
| 10 wk (70 d) | 44.79 | 36.70 | 43.69 | 42.60 | 43.59 | 3.145 | 0.689 | 0.174 | 0.463 |
| 13 wk (91 d) | 42.34 | 42.01 | 46.36 | 42.23 | 42.61 | 4.257 | 0.753 | - | - |
| 22 wk (150 d) | 41.51 | 53.71 | 41.74 | 42.00 | 42.44 | 2.830 | 0.647 | - | - |
| Albumin (g/L) | |||||||||
| 10 wk (70 d) | 32.54 | 29.85 | 31.28 | 34.09 | 34.07 | 2.185 | 0.763 | 0.592 | 0.675 |
| 13 wk (91 d) | 32.55 | 31.64 | 32.23 | 30.65 | 29.42 | 3.230 | 0.554 | - | - |
| 22 wk (150 d) | 31.09 | 30.84 | 31.79 | 32.32 | 31.11 | 3.258 | 0.964 | - | - |
| Globulin (g/L) | |||||||||
| 10 wk (70 d) | 12.25 | 9.85 | 10.71 | 9.69 | 11.37 | 2.333 | 0.265 | 0.862 | 0.638 |
| 13 wk (91 d) | 9.79 | 10.37 | 12.13 | 11.58 | 13.19 | 1.672 | 0.297 | - | - |
| 22 wk (150 d) | 10.42 | 12.95 | 9.95 | 10.86 | 11.32 | 1.505 | 0.353 | - | - |
| IgG (g/L) | |||||||||
| 10 wk (70 d) | 9.49 | 8.03 | 7.00 | 8.36 | 10.39 | 0.727 | 0.337 | 0.295 | 0.308 |
| 13 wk (91 d) | 8.45 | 8.65 | 7.30 | 8.77 | 8.84 | 0.809 | 0.851 | - | - |
| 22 wk (150 d) | 8.69 | 9.88 | 9.14 | 9.45 | 10.09 | 0.377 | 0.439 | - | - |
| IgM (g/L) | |||||||||
| 10 wk (70 d) | 0.84 | 0.75 | 0.75 | 0.76 | 0.73 | 0.037 | 0.726 | 0.894 | 0.835 |
| 13 wk (91 d) | 0.84 | 0.75 | 0.74 | 0.72 | 0.69 | 0.011 | 0.582 | - | - |
| 22 wk (150 d) | 0.88 | 0.81 | 0.82 | 0.81 | 0.78 | 0.029 | 0.893 | - | - |
| IgA (g/L) | |||||||||
| 10 wk (70 d) | 1.34 | 1.23 | 1.17 | 1.30 | 0.96 | 0.062 | 0.732 | 0.830 | 0.387 |
| 13 wk (91 d) | 1.34 | 1.24 | 1.18 | 1.21 | 1.01 | 0.071 | 0.582 | - | - |
| 22 wk (150 d) | 1.68 | 1.91 | 1.75 | 1.61 | 1.32 | 0.119 | 0.937 | - | - |
| ALP (U/L) | |||||||||
| 10 wk (70 d) | 341.84 | 436.41 | 462.06 | 370.95 | 372.79 | 28.385 | 0.208 | 0.935 | 0.726 |
| 13 wk (91 d) | 410.52 | 457.15 | 415.10 | 361.20 | 382.03 | 25.787 | 0.140 | - | - |
| 22 wk (150 d) | 404.65 | 405.53 | 426.23 | 427.03 | 435.39 | 34.230 | 0.391 | - | - |
SEM, standard error of the mean; Tr, treatment; IgG, immunoglobulin G; ALP, alkaline phosphatase.
a–c
Within a row, means with different superscripts differ (p<0.05).