Table 2.
Analysis of parasite size and reproductive parameters according to parasite species, fish species, their interaction, population, and, for parasite size, Pomphorhynchus load (the number of parasites per individual fish) and sex, and for reproductive parameters parasite size (a) Parasite size, and male testes volume; (b) female reproductive parameters, represented by the two first PCA axis (main contributing variable provided; see Fig. S3b). Infection type refers to monospecific or heterospecific infection with respect to Pomphorhynchus species.
| (a) | ||
|---|---|---|
| Dependant variable Predictor variable | Parasite size Chi2 (df; P value) | Testes Chi2 (df; P value) |
| Parasite load | 0.8 (1; P = 0.37) | |
| Parasite sex | 24.1 (1; P < 0.0001) | / |
| Parasite size | / | 137.8 (1; P < 0.0001) |
| Fish sp. | P.laevis: 8.67 (1; P = 0.003)P. tereticollis: 2.69 (1; P = 0.10) | 5.3 (2; P = 0.07) |
| Parasite sp. | in barbel: 44.5 (1; P < 0.0001)in chub: 0.09 (1; P = 0.76) | 1.5 (2; P = 0.47) |
| Fish * Parasite sp. | 34.8 (1; P < 0.0001) | 0.02 (1; P = 0.87) |
| Infection type $ | 2.01 (1; 0.15) | / |
| Population |
1.6 (1; P = 0.20) |
0.4 (1; P = 0.63) |
| (b) | ||
| Dependant variable Predictor variable | PC 1 ∼ nb eggs, prop.egg3 Chi2 (df; P value) |
PC2∼ nb ovarian balls Chi2 (df; P value) |
| Parasite size | 43.4 (1; P < 0.0001) | 0.72 (1; P = 0.39) |
|
P. laevis in chub vs P. tereticollis in barbel |
21.3 (1; P < 0.0001) | 4.33 (1; P = 0.04) |
| Population | 0.1 (1; P = 0.31) | 3.53 (1; P = 0.06) |
Significant values are indicated in bold.