Table 2.

Effect of treatments, changes in plasma concentration of malondialdehyde (ΔMDA) and antioxidant activity (ΔTAS) on changes in ornamentation (Δcomb) at different sampling times (S1–S2; S2–S3).

		Δcomba S1–S2		Δcomba S2–S3
dependent variable:	d.f.	F	p-value	F	p-value
TTreatb	1,19	84.12	<0.001	0	0.96
PTreatc	1,19	1.09	0.31	4.98	<0.05
TTreat×PTreat	1,19	0.06	0.8	3.19	0.09
ΔMDAd	1,19	13.07	<0.01	1.29	0.27
ΔTASe	1,19	0.46	0.51	8.54	<0.01
ΔMDA×TTreat	1,19	4.09	<0.05	0.82	0.37
ΔTAS×TTreat	1,19	0.39	0.54	1.12	0.29
ΔMDA×PTreat	1,19	2.62	0.12	3.16	0.09
ΔTAS×PTreat	1,19	0.02	0.88	0.3	0.59

^aΔcomb was calculated as the difference between the final and initial comb area, corrected for the initial comb area.

^bTTreat=males, sham implanted (T−) versus testosterone implanted (T+) males.

^cPTreat=parasite treatment, categorical: P− males: not challenged; P+ males: challenged with infective T. tenuis larvae.

^dΔMDA was calculated as the difference in MDA concentration between S2 and S1 corrected for MDA concentration at S1.

^eΔTAS was calculated as the difference in TAS concentration between S2 and S1 corrected for TAS concentration at S1.