Table 1.
Overview of the timing of the experiment, procedures and sampling.
Table 2.
Sample sizes for the data sampling according to treatment (4 groups), site (moor 1 or 2) and sampling time (C1 or C2).
Figure 1.
Effects of testosterone and parasite treatments on mean±s.e. (a) plasma concentration of testosterone (ng /ml) and (b) comb area (mm2) of red grouse.
T0: control implanted; T+: testosterone implanted; P0: purged of worms; P+: challenged with T. tenuis infective larvae.
Table 3.
Generalised Linear Mixed Models testing for treatment effects on changes over time in testosterone concentration and ornamentation (comb area).
Figure 2.
Mean±s.e. levels of corticosterone (pg / mm) in feathers of red grouse according to hormone and parasite treatments.
T0: control implanted; T+: testosterone implanted; P0: purged of worms; P+: challenged with T. tenuis infective larvae. Numbers above bars are sample sizes.
Figure 3.
Relationship between corticosterone (pg/mm) in feathers and final number of T. tenuis worms in red grouse by treatment.
T0: control implanted; T+: testosterone implanted; P0: purged of worms; P+: challenged with T. tenuis infective larvae.
Figure 4.
Relationship between corticosterone (pg/mm) in feathers and changes in comb area (mm2) of male red grouse between C1 and C2, according to treatment.
a) T0: control implanted males; b) T+: testosterone implanted males. Parasite treatments: P0: purged of worms; P+: challenged with T. tenuis infective larvae.