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Calculate live weights by cohort and life stage

Source: R/core_model_weights.R
calc_cohort_weights.Rd

Determines the initial, potential final, and slaughter live weights for a given sex–age cohort based on species‑specific biological parameters. The function assigns weights according to the animal's life stage (juvenile, subadult, adult) and the sex of the cohort.

Usage

calc_cohort_weights(
  cohort_short,
  live_weight_female_adult = NA_real_,
  live_weight_male_adult = NA_real_,
  live_weight_at_birth = NA_real_,
  live_weight_female_at_slaughter = NA_real_,
  live_weight_male_at_slaughter = NA_real_,
  live_weight_at_weaning = NA_real_
)

Arguments

cohort_short

Character. Sex- and age-specific cohort code describing the production stage of the animals. Supported values include:

  • FA: adult females (from age at first parturition)

  • FS: sub-adult females (from weaning to age at first parturition)

  • FJ: juvenile females (from birth to weaning)

  • MA: adult males (from age at first breeding)

  • MS: sub-adult males (from weaning to age at first breeding)

  • MJ: juvenile males (from birth to weaning)

live_weight_female_adult

Numeric. Live weight of adult females (kg)

live_weight_male_adult

Numeric. Live weight of adult males (kg)

live_weight_at_birth

Numeric. Live weight of the animal at birth (kg).

live_weight_female_at_slaughter

Numeric. Slaughter weight of female sub-adult animals (kg).

live_weight_male_at_slaughter

Numeric. Slaughter weight of male sub-adult animals (kg).

live_weight_at_weaning

Numeric. Live weight of the animal at weaning (kg)

Value

A named list with:

live_weight_cohort_initial

Numeric. Live weight at the beginning of the cohort stage (kg).

live_weight_cohort_potential_final

Numeric. Potential final live weight attainable at the end of the cohort stage in the absence of offtake (kg). (For juveniles: equals weaning weight; For subadults: equals adult live weight; For adults: equals adult live weight)

live_weight_cohort_at_slaughter

Numeric. Live weight at slaughter for animals removed from the cohort (kg).

live_weight_mature_stage

Numeric. Mature (adult) live weight that the animal can attain under given biological and management conditions (kg).

Details

The function attributes weights according to cohort and animal type:

  • Juveniles ("FJ", "MJ"):

    • live_weight_cohort_initial = live_weight_at_birth

    • live_weight_cohort_potential_final = live_weight_at_weaning

    • live_weight_cohort_at_slaughter = live_weight_at_weaning

  • Subadults ("FS", "MS"):

    • live_weight_cohort_initial = live_weight_at_weaning

    • live_weight_cohort_potential_final = adult weight for the cohort sex (live_weight_female_adult for "FS", live_weight_male_adult for "MS")

    • live_weight_cohort_at_slaughter = subadult slaughter weight for the cohort sex (live_weight_female_at_slaughter for "FS", live_weight_male_at_slaughter for "MS")

  • Adults ("FA", "MA"):

    • live_weight_cohort_initial = live_weight_female_adult for "FA", and live_weight_cohort_initial = live_weight_male_adult for "MA"

    • live_weight_cohort_potential_final = adult weight for the cohort sex

    • live_weight_cohort_at_slaughter = adult weight for the cohort sex

This function is part of the run_weights_module().

See also

run_weights_module