FSH plasma levels in experiments 1 and 2 are shown in Figures 5 and 6, respectively. Nondetectable plasma FSH levels (< 0.4 ng/ml, 0.04 ng/RIA tube) were counted as 0 for statistical analysis. Plasma levels of FSH were generally higher than for LH and were within the detection range in most fish in all groups except in T-treated fish sampled in July and September. In spring, plasma FSH levels were significantly higher in mature than in immature males (p < 0.01). levitra super active plus
In sham-operated fish, the highest FSH levels were found in July (p < 0.001 compared with September and November). The levels were consistently lower in castrated fish than in sham-operated ones ip < 0.01, July; p < 0.001 September, both experiments 1 and 2; p < 0.001, November). As in the sham-operated fish, plasma FSH levels of castrated fish were higher in July than in September and November (p < 0.001 in both comparisons). Compared to castrated controls, T-treated fish displayed lower plasma FSH levels in July (p < 0.001) and higher levels in November (p < 0.001), whereas there was no significant difference in September. The 11KA treatment significantly raised plasma FSH levels as compared to those in castrated fish at all three samplings (p < 0.001 in July and September, both experiments 1 and 2; p < 0.05 in November); the effect of 11KA was, however, far larger in July than at the other time points.
FIC. 5. Effects of castration on plasma levels of FSH in male salmon parr in experiment 1. Means ± SEM for initial controls and sham-operated and castrated fish are shown; number of fish is indicated on top of bars. For statistics, see Results.
FIG. 6. Effects of castration and treatment of castrated fish with T or 11 KA on plasma levels of FSH in male salmon parr in experiment 2. Means ± SEM for mature and immature initial controls, sham-operated fish, castrated fish, and castrated fish treated with T or 11 KA are given. In some groups, means and SEM are too small to show. Number of fish is indicated on top of bars. For statistics, see Results.