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Table 1 Parameters for herd management and population dynamics used in a Mycobacterium avium paratuberculosis infection dynamics model within a structured dairy herd

From: Predicting fadeout versus persistence of paratuberculosis in a dairy cattle herd for management and control purposes: a modelling study

Notation Value Definition Source
σ B 0.07 Mortality rate of calves at birth a, [32]
σ m 0.206 Exit rate of male calves, weeks 2 to 4 (per week)  
σ C1 0.015 Death rate of female calves, weeks 1 and 2 (individual housing facilities) (per week) [32]
σ C2 0.0035 Death rate of female calves, weeks 3 to weaning (collective housing facilities) (per week) [33]
σ C3 0.00019 Death rate of heifers from weaning to first calving (per week) b
σ h 0.11 Sale rate of bred heifers 10 weeks before 1st calving b
σ Ai 27, 25, 31, 31, 62 Yearly culling rate of cows in parity 1, 2, 3, 4 and above 5 respectively (%) a, [34]
m 2 Maximal age in individual pen (weeks) [13]
w 10 Weaning age (weeks) [13]
y 52 Age when entering the young heifer group (weeks)  
nb 2 Number of neighbours for a calf in an individual pen b
h 91 Age at first artificial insemination (weeks) a
cal 130 Age at first calving (weeks) a,b
cci 56.3 Calving-to-calving interval (weeks) a,b
b 5 Quantity of colostrum fed to calves (L/day for 3 days) b
d 7 Quantity of milk fed to calves after 3 days (L/day/calf) b
prop 0.85 Proportion of lactating cows a
ε 25 Quantity of milk or colostrum produced (L/day/cow) a
f 1 0.5 Quantity of faeces produced by a non-weaned calf (kg/day) b
f 2 5.5 Quantity of faeces produced by a weaned calf (kg/day) b
f Y 10 Quantity of faeces produced by a heifer (kg/day) b
f A 30 Quantity of faeces produced by a cow (kg/day) b
Graz [14-46] Grazing period (1 being the first week of the year) b
K c 110 Number of cows above which the heifer selling rate increases -
  1. a Agricultural statistics
  2. b Expert opinions