Concept: Run-out tolerance by livestock sector
Dairy parlour: <12 hours. Broiler brooding (day 1–7): <2 hours in winter. Farrowing creep: <4 hours. Layer barn: Days, not hours.
Last reviewed 2026-10-31
Confidence: Estimated — windows are field-experience-based, not published.
Run-out tolerance by sector
| Sector | Run-out window | What fails first |
|---|---|---|
| Dairy parlour | <12 hours | Wash cycle → milk pickup refused → DFO infraction (see Regulation: Ontario Milk Act — propane run-out as regulatory exposure on dairy); calf milk warming |
| Broiler brooding (day 1–7) | <2 hours in winter | Chick mortality from cold stress; ammoniated wet litter follows |
| Farrowing creep | <4 hours | Piglet pre-weaning mortality; sow stress |
| Turkey poult brooding | <2 hours | Same mechanism as broiler, higher temperature |
| Layer barn | Days, not hours | Water-line freeze; production drop |
| Beef finishing | Days | Office / shop heat only |
Why the windows are this short
- Dairy: the next milking happens on a fixed schedule (typically 2× or 3× daily), and the wash must happen before each milking. CIP needs 71–77°C start temperature (see Concept: Dairy parlour propane load profile); without hot wash, the milk truck refuses load.
- Broiler / turkey brooding: chicks and poults cannot thermoregulate at hatching — required body temperatures are met by environmental heat. A 2-hour gap in winter at a target of 32°C ambient drops to lethal cold-stress territory quickly.
- Farrowing creep: piglets cannot thermoregulate in their first 48 hours. Lethargic piglets do not nurse; a heat failure cascades into pre-weaning mortality.
- Layer / beef: insulating mass and adult animal heat output buffer the system. Days, not hours.
Sources
Field experience consolidated from SW Ontario livestock distribution practice. Published primary sources for tolerance windows do not exist — these are operational benchmarks, not research outputs.
On the Boucher & Jones site: Agriculture