DeepLoop Team · 2026-09-07
Pig Water: Meter It Like the Nutrient It Is
Water is the one nutrient every pig needs most and the one almost nobody measures per pig. Get it wrong and feed intake follows it down - because a pig that cannot drink enough will not eat enough.
Two numbers that both move with the pig
The daily requirement roughly doubles across the barn: DanBred puts a 15-45 kg grower at 4-8 litres a day and a 45-100 kg finisher at 6-10, then a lactating sow at 35-50. The flow rate at the drinker splits by source - for weaners SEGES and DanBred say 0.5-0.8 L/min; for finishers DanBred allows up to 2.0 while PIC sets 1.0 and Hypor 1.0-1.5. Set it once at housing for the whole herd and it is wrong at both ends: too slow starves the big pigs, too fast lets the small ones waste it.
Drunk is not the same as delivered
The manuals talk about a 2-3:1 water-to-feed ratio - but that is water drunk. What leaves the pipe is a different number entirely, set by the drinker you hung, not the pig underneath it. The gap between what the pig takes in and what runs to the slurry pit is where cost and mess live, and it is invisible to a barn-wall meter.
Daily water requirement by stage and drinker flow-rate targets across five breeders, redrawn from the source manuals.
A figure on the drinker gap
A Brazilian team on a commercial farm ran 1,104 nursery piglets across three setups: an automatic bowl at two per pen, the same bowl at four per pen, and a swing nipple at four per pen - then metered the water. Over the nursery phase the swing nipple drew 7.27 litres per pig per day; the bowls, 2.55-2.69. The water-to-feed ratio at the drinker was 13.85 L/kg on the nipple against about 6 on the bowls - more than double the water for the same feed. And it left as slurry: 6.5 litres of liquid manure per pig per day on the nipple versus roughly 1.7 on the bowls.
From the nursery drinker study - swing nipples drew more than double the water of bowls for the same feed, most of it leaving as slurry.
When did you last time a drinker?
The whole page rests on numbers most barns never check. Drinker height, pigs per drinker, and the actual flow rate under a stopwatch and a litre cup decide whether the pig standing there gets what the table says it needs. Water quality thresholds where DanBred and Hypor disagree by up to twenty-fold add another layer - the delivered number is the one that matters, and it is rarely the one measured.
Where this is heading
The page is missing one number: what each pen actually drinks. DeepLoop is working on reading that continuously instead of metering it once at the barn wall - because water is the first nutrient to fail and the last one anyone watches.