22 production-system overlays — 12 beef archetypes, 10 sheep — each with its own multiplier table re-weighting the bioeconomic objective for the producer's actual operation. The same closed-form derivation; the right trait weights, the right way, for the right system. The codes you find in the source tree; the codes the methodology page references; the codes the country deep-dives walk through.
Each beef system carries its own multiplier table over the canonical EBV/EPD vocabulary. Values > 1 amplify the trait's weight relative to the industry default; values < 1 dampen it; negative values are penalties (lower is better). Code names match the JavaScript registry in core/js/production-system-modifier.js.
Housed bull (ungtjur). Yearling weight + EUROP conformation + hoof health emphasised; pasture-growth and maternal traits dampened (most progeny slaughtered young).
Hanwoo intensive. Marbling (1++/1++A achievement) and carcass weight dominate; maternal traits dampened — terminal-style economic objective.
Wagyu long-fed (400-600d). Marbling is everything. Carcass weight and intramuscular fat strongly amplified; growth softer; maternal traits weak.
US cow-calf. WW + maternal + stay-ability dominate; carcass traits weakly weighted (calves sold at weaning, not slaughter).
US backgrounder. Yearling weight and RFI dominate; carcass traits start to matter where feedyard placement contracts grade-out projections.
US feedyard. Marbling (Choice/Prime achievement) dominates at 3-4× cow-calf level; RFI heavily weighted; maternal traits zeroed.
Brazilian confinamento. Yearling weight + carcass weight + ribeye emphasised; lower marbling weight because Brazilian premium structure differs from US/AU choice grades.
Indigenous tropical breeds (Bonsmara, Brahman, Nguni, Drakensberger). Maternal + heat tolerance + parasite resistance emphasised; marbling dampened (tropical breeds rarely target marbling premiums).
Dairy-beef cross. Beef-bull progeny out of dairy cows for the slaughter market. Calving ease at birth from the dairy cow side is critical; growth and carcass traits drive the slaughter return.
Pastoral cow-calf. Weaning weight + maternal + calving ease emphasised (most progeny sold at weaning); carcass traits dampened. The general pastoral archetype underlying many country-specific overlays.
Argentine pampas grass-fed. Yearling weight 1.4× (Cuota Hilton 19-25mo window), rib eye area 1.4× (Hilton conformation grid), mature cow weight 0.55× (pampas stocking-rate constraint), marbling 0.85× (EU grid less steep than US Choice/Prime). Self-replacing outdoor system; fertility and calving ease elevated.
Hanwoo intensive (alias). Discoverable shorter form pointing to the 30-month finishing archetype. Same multipliers and reasons as hanwoo_intensive_30mo.
Sheep production carries a much wider economic-objective spread than beef — wool-primary, dual-purpose maternal, terminal sire, shedding, dairy and pelt-primary are not just trait re-weighting but structurally different industries. Genemap exposes each as its own overlay.
Pelt-primary. Pelt quality (Pälskvalitet) and curl (Lockighet) weighted 3-4×; carcass weight dampened (light slaughter for pelt curl quality).
Wool-primary Merino. Clean fleece weight 2.5×, fibre diameter strongly rewarded (lower is better — micron premium).
Dual-purpose maternal (Romney, Coopworth, Border Leicester etc.). Lambs weaned per ewe doubled (NLW 2×); balanced carcass/wool emphasis.
Terminal sire (Suffolk, Texel, Poll Dorset, Hampshire). Lean weight + muscle depth weighted heavily; wool zeroed; maternal dampened (progeny all slaughtered).
Shedding sheep / hair sheep. Worm egg count (parasite resistance) heavily rewarded; wool traits zeroed; maternal emphasised for tropical / sub-tropical adaptation.
AU Merino wool-primary. CFW 2.7× and FD strongly rewarded (steeper AU micron premium than global default); SL and YLD AU-specific axes; carcass softened.
AU maternal composite. NLW 2.1× (load-bearing for prime lamb); carcass traits emphasised for terminal-progeny side; coarse wool residual.
AU shedder. WEC (worm resistance) 3-7× harder than other AU sheep systems; wool zeroed; ewe-size penalised more steeply (no wool revenue offset).
NZ pastoral. NLW 2.2× (load-bearing on hill country); survival 1.3× (lambing exposure); mature ewe weight penalty 1.4× (12-month grazing cost on rough country).
Dairy sheep. Milk yield 4×, milk protein 1.8×, somatic-cell count strongly penalised; meat/wool dampened (milk-led economics).
The engine derives every trait's industry-default weight from the closed-form bioeconomic formula. The selected production-system code then applies its multiplier table over the top — amplifying load-bearing traits, dampening secondary ones, zeroing wool for terminal-sire rams, zeroing maternal for feedyard finishing. The producer-fit closed-loop calibration multiplier sits on top of that, tuning to their actual kill data.
The function is MGT_PRODUCTION_SYSTEM.apply(baseResult, species, { productionSystem: code }) — it lives at core/js/production-system-modifier.js. Override any multiplier on the rank page and the engine re-derives in milliseconds.
For academic teams referencing a specific production-system overlay in published work, use the JSON shape resolved from the registry:
MGT_PRODUCTION_SYSTEM.BEEF_MODIFIERS['us_feedyard']
{ label: "US feedyard / finishing",
multipliers: { MARB: 3.4, REA: 2.3, RFI: 1.8, ... },
grading_default: ["USDA_QualityGrade", "CAB_Prime"],
reasons: [...] }
Every system code is stable across versions. New countries are added by addition, never by re-shaping an existing code. See the for-researchers page for the canonical citation format and the academic-collaboration inbound, and the engine architecture page for the full layered stack the production-system modifier sits inside.