Table 1 Comparisons between the infection and immune dynamics of the three rodent species

Peak bacterial load (cells ml⁻¹)

351,600 ± 87,479

8804 ± 4115

363,175 ± 106,916

F_2,11 = 7.37, P = 0.009**

Overall bacterial load (cells ml⁻¹)

49,389 ± 12,860

1057 ± 547

64,906 ± 18,656

F_2,11 = 7.59, P = 0.00848**

Day post-infection of peak antibody level

42.0 ± 19.6

66.0 ± 2.45

74.8 ± 24.4

F_2,11 = 0.981, P = 0.406

Rate of antibody increase during primary infection (μg ml⁻¹ day⁻¹)

0.320 ± 0.0575

0.344 ± 0.0266

0.290 ± 0.0187

F_2,11 = 0.422, P = 0.666

Rate of antibody increase during secondary infection (μg ml⁻¹ day⁻¹)

0.123 ± 0.0275

0.180 ± 0.0300

0.172 ± 0.0403

F_2,7 = 0.663, P = 0.545

Peak antibody levels

(μg ml⁻¹)

149 ± 63.5

110 ± 20.0

309 ± 169

F_2,11 = 1.22, P = 0.332

Overall primary antibody response (μg ml⁻¹)

82.8 ± 31.5

67.8 ± 11.3

145 ± 67.6

F_2,11 = 1.04, P = 0.386

Overall secondary antibody response (μg ml⁻¹)

287 ± 169

339 ± 139

549 ± 146

F_2,8 = 0.842, P = 0.466

Day post-infection of peak antibody level (days) versus peak bacterial load (cells ml⁻¹)

-1.11 × 10^–4 x + 81.1, R² = 0.247

9.36 × 10^–5 x + 65.2, R² = 0.0250

1.22 × 10^–4 x + 30.5, R² = 0.284

F_2,8 = 1.43, P = 0.295

Overall primary antibody response (μg ml⁻¹) versus overall bacterial load (cells ml⁻¹)

8.49 × 10^–4 x + 40.9, R² = 0.120

8.77 × 10^–3 x + 58.6, R² = 0.180

2.94 × 10^–3 x – 45.5, R² = 0.659

F_2,8 = 0.872, P = 0.454

Difference in the day post-infection of peak antibody level of the primary and secondary responses

7.50 ± 7.38

46.7 ± 8.52

30.0 ± 7.38

F_2,8 = 6.23, P = 0.023

Difference in the peak antibody level (μg ml⁻¹) of the secondary and primary immune responses

369 ± 215

503 ± 248

801 ± 215

F_2,8 = 1.05, P = 0.394

Difference in the overall antibody response (μg ml⁻¹) of the secondary and primary immune responses

219 ± 124

281 ± 144

454 ± 124

F_2,8 = 0.948, P = 0.427