Abstract: In multi-story swine farms, shared feed delivery lines transport multiple feed types. Switching between feeds requires a batch of sacrificial feed (industry term: "flush feed") to purge residual feed from pipelines, causing both direct feed loss and additional electricity consumption from equipment operation. Current manual scheduling triggers by feed level without cross-floor consolidation, leading to random feed-switching frequency and reliance on human compliance for isolation protocols. This study aimed to develop a feed delivery scheduling method that reduced flush feed loss and electricity consumption without equipment modifications. Three rules were formulated from farm isolation protocols: an isolation combination list, flush feed quantity, and isolation interval. Three sorting strategies were applied: same-feed consolidation, floor-based clustering, and dedicated-feed batch concentration. Together, these formed a delivery sequence table and feed batch ledger directly executable by the central control system, converting isolation compliance from voluntary to algorithm-enforced. The method was applied in a 6-floor swine house with 24 feeding points and approximately 3 600 pigs over 10 consecutive production days, with a 10-day baseline of the same caliber for comparison. The isolation protocol execution rate reached 100% with no high-risk cross-contamination events. Daily isolation switches decreased from 4.4 to 2.0. Flush feed net loss decreased from 88 to 40 kg/d (daily savings of approximately 168 CNY). Average daily measured electricity consumption dropped from 39.5 to 28.9 kWh (a 26.7% reduction). The complete cost per flush was approximately 72 CNY (feed: 70 CNY; electricity: 1.8 CNY), with feed loss reduction benefits of approximately 24 times those of electricity savings. The method requires no equipment or pipeline modifications—only adjustment of feed delivery sequence, with no adverse effects on production rhythm or pig feeding. Farms without scheduling software could still achieve the goal of cost savings by manually following four rules.

Key words: multi-story swine farming, feed delivery, flush feed, production scheduling, energy saving