Table 1

Week at sample collection
		Week 1	Week 2	Week 3	Week 4	Week 5
GSH-Px	Summer	98.7 ± 15.0^a	140.5 ± 6.3^a	70.5 ± 5.5^a	74.9 ± 3.9	70.4 ± 4.8^a
GSH-Px	Fall	41.6 ± 3.3^b	52.2 ± 3.9^b	36.4 ± 2.4^b	65.5 ± 4.0	39.2 ± 2.6^b
SOD	Summer	9.1 ± 0.6	9.8 ± 1.0	11.4 ± 1.5^A	19.8 ± 1.0^a	12.6 ± 1.0^A
SOD	Fall	7.7 ± 0.4	10.1 ± 1.2	4.0 ± 0.2^B	8.6 ± 0.9^b	18.0 ± 1.0^B
TBARS	Summer	8.1 ± 0.6	5.2 ± 0.5^A	7.9 ± 1.0	4.9 ± 1.0	7.7 ± 1.3
TBARS	Fall	7.5 ± 0.8	8.5 ± 1.2^B	6.9 ± 0.7	4.1 ± 0.9	6.3 ± 0.5

^a,b Means within column with different superscripts for each measured parameters are different (P<0.05).
^A,B Means within column with different superscripts for each measured parameters are different (P<0.05).

Table 1: Mean ± SEM for activities of plasma glutathione peroxidase (GSH-Px;nmol/min/ml) and superoxide dismutase (SOD; units/ml), and concentration of thiobarbituric acid reactive substances (TBARS; nmol/ml) in Jersey calves born and raised in summer or fall.