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Table 1 Definitions and values of the main variables, functions and parameters in the model

From: Agricultural landscape and spatial distribution of Toxoplasma gondii in rural environment: an agent-based model

Process Definition Value Ref.
  Number of X patches 230  
  Number of Y patches 230  
Environment
Diffusion Percentage of contamination diffusing to the 8 neighboring patches 10%  
Decay Decontamination rate 1/125 day−1 [31]
Rodents
Birth Birth rate (b m ) 10/365 day −1 Value in the range of [27] and [32]
Density dependent probability of birth of 1 juvenile by an adult rodent b m – 0.5(b m m m ) × N m,i /K m,i  
Mortality Mortality rate (m m ) 2/365 [32]
Density dependent probability of rodent mortality m m  + 0.5(b m m m ) × N m,i /K m,i  
Density Nm,i = number of mice in the 46 × 46 patches (=460 × 460 m2) subdivision i   
K m,i = local carrying capacity of rodents (=Initial number of rodents) in the 46 × 46 patches subdivision i 300 *
Maturation Weaning age of rodents 21 days [27]
Age at sexual maturation of rodents 50 days [27]
Movement Range of patches travelled (in any direction) randomly chosen 0-2 patches [33]
Infection Probability of vertical transmission 0.15 Value in the range of [27] and [32]
Probability of rodent infection after ingesting one oocyst 1 [34]
Number of contact between rodent and the patch/day 12 *
Probability of infection from the environment while on patch j 1-(1-p conta, j )12 See above
p conta, j  = level of contamination of patch j   
Cats
Birth Birth rate (b c ) 2.4/365 day −1 [32]
Density dependent probability of birth of 1 juvenile by an adult cat b c – 0.5(b c m c ) × N c /K c  
Mortality Mortality rate (m c ) 0.6/365 day−1 [32]
Density dependent probability of cat mortality m c  + 0.5(b c m c ) × N c /K c  
Density N c  = total number of cat on the entire site area   
  Carrying capacity of cats (=Initial number of cats) 100 order of magnitude observed in the field [19]
Maturation Weaning age of cats 50 days [27]
Age at sexual maturation of cats 240 days [27]
Movement Random cat location per activity within their homerange   Estimated from maximum distance from [29, 30]
Cat homerange radius picked in a gamma distribution Γ(2, 0.014)
Infection Probability of predation of rodent within 1 patch (=10 m) of a cat 1 *
Probability of cat infection after eating an infected rodent 1 [34]
Probability of cat infection after ingesting one oocyst 10−3 [34]
Probability of infection from the environment while on patch j 10−3 × p conta,j see above
Prepatent period before oocyst shedding 7 days [10]
Duration of infectiousness (=oocyst shedding period) 14 days [10]
Environmental contamination Probability of cat shedding oocysts per day 1 [35]
Level of contamination on a patch j after shedding of oocyst by one infected cat 0.01 + p conta,j See text
  1. * chosen to obtain realistic values of rodent predation, rodent prevalence.