As the supplemental vitamin E level increased, the
serum α-tocopherol concentrations increased quadratically
(P < 0.01) at the 7-d period but linearly (P < 0.01)
at each of the subsequent weekly measurement periods
(Table 3).
Serum α-tocopherol concentrations were highest at
weaning but declined in all treatment groups by 7 d
after weaning (Table 3). When the basal diet was fed,
serum α-tocopherol concentrations declined linearly (P
< 0.01) from 7 to 42 d after weaning. For the groups
fed supplemental vitamin E, a quadratic (P < 0.01) response
in serum α-tocopherol concentrations occurred
as the experiment progressed. This resulted in a decline
in serum α-tocopherol from 7 to 21 d after weaning,
followed by an increase to 42 d. Compared with pigs
fed 100 to 200 IU vitamin E/kg diet the pigs fed the 20
to 80 IU vitamin E level had lower serum concentrations
and the decline was greater from the 7- to 21-d
period. In the treatment groups in which higher vitamin
E levels were provided the serum α-tocopherol concentration
seemed to be more uniform between each weekly
measurement period. Consequently, there was a time