Table 9.
Item | INR | AAC | SEM | P-value |
---|---|---|---|---|
Co, mg/kg | ||||
Cotyledon | 0.494 | 0.533 | 0.090 | 0.77 |
Calf birth | 0.202 | 0.188 | 0.015 | 0.51 |
Calf 24 h after birth | 0.153 | 0.148 | 0.010 | 0.73 |
Calf early life | 0.223 | 0.228 | 0.010 | 0.73 |
Calf weaning | 0.166 | 0.165 | 0.009 | 0.94 |
Cu, mg/kg | ||||
Cotyledon | 8.38 | 9.07 | 0.92 | 0.61 |
Calf birth | 394 | 399 | 19 | 0.87 |
Calf 24 h after birth | 303 | 291 | 20 | 0.67 |
Calf early life | 84.5 | 75.9 | 14.3 | 0.67 |
Calf weaning | 70.4 | 73.7 | 9.3 | 0.80 |
Mn, mg/kg | ||||
Cotyledon | 18.9 | 18.4 | 5.46 | 0.95 |
Calf birth | 5.96 | 6.06 | 0.34 | 0.83 |
Calf 24 h after birth | 4.70 | 4.83 | 0.29 | 0.75 |
Calf early life | 11.6 | 12.0 | 0.5 | 0.44 |
Calf weaning | 9.19 | 8.80 | 0.19 | 0.17 |
Zn, mg/kg | ||||
Cotyledon | 90.9 | 93.4 | 3.3 | 0.60 |
Calf birth | 823 | 869 | 79 | 0.69 |
Calf 24 h after birth | 676 | 637 | 79 | 0.73 |
Calf early life | 154 | 148 | 9 | 0.59 |
Calf weaning | 137 | 142 | 5 | 0.42 |
1INR and AAC cows received the same amount of supplemental Co, Cu, Mn, and Zn from sulfate sources or Availa 4 (Zinpro Corporation, Eden Prairie, MN). Cows were assigned to the experiment at 117 ± 2 d of gestation (day 0).
2Cotyledon and calf liver samples (needle biopsy; Arthington and Corah, 1995) were collected within 8 h after calving. A total of 32 placentas were retrieved (16 placentas/treatment) for cotyledon collection. Calf liver samples were collected again 24 h after birth, when calves were 43 ± 0.5 d of age (early life), and at weaning (day 367). Concentrations of Co, Cu, Mn, and Zn were determined by the Michigan State University Diagnostic Center for Population and Animal Health (East Lansing, MI; Braselton et al., 1997). All liver samples were collected from 30 cows of each treatment randomly selected on each sampling day.