Table 1.
Model parameters and their values
| Symbol | Description | Values |
|---|---|---|
| Pti | Performance for animal i at time t | |
| Cti | Pathogen number in animal i at time t | |
| Rti | Immune response in animal i at time t | |
| It | Number of infected animals in the population at time t | |
| Pt | Population performance at time t | |
| ΔEP | Incremental effectiveness for Pt over the T period | |
| ΔEI | Incremental effectiveness for It over the T period | |
| N | Population size | 30 |
| T | Time duration | 300 |
| Cmin | Pathogen number necessary for infection | 10 |
| CMax | Maximum number of pathogens | 500 |
| PMax | Maximum performance | 100 |
| γ | Per-capita pathogen growth rate | 0.5 |
| β | Transmission rate | 0.1; 0.5 |
| μ | Maximum per-capita pathogen killing rate | 0.25; 1.0 |
| ω | Maximum performance loss per pathogen | 0.1; 0.2 |
| ciρ | Marginal costs of resistance | U [0, 0.1]; U [0.1, 0.2]; U [0.2, 0.5] |
| ciλ | Marginal costs of tolerance | U [0, 0.1]; U [0.1, 0.2]; U [0.2, 0.5] |
| ρi | Extra investment in resistance | U [0, 1]; U [0,0.5]; U [0.9, 1] |
| λi | Extra investment in tolerance | U [0, 1]; U [0, 0.5]; U [0.9, 1] |
| hi | Rate of increase for the immune index | U [0, 0.001]; U [0, 0.01]; U [0, 0.1] |