Dry Matter Intake (DMI)

Dry matter intake (DMI) is the pounds of dry matter a cow consumes per day. It’s the single largest controllable driver of milk production on a dairy operation.

Typical DMI for a high-producing milking cow runs 50–60 lbs/day. DMI varies by parity (lactation number), days in milk, body condition, environmental temperature, and ration palatability — all of which interact.

The math behind why DMI matters:

• Milk production is roughly proportional to DMI.
• Anything that depresses intake — empty bunks, sorting, slug feeding, heat stress, lameness — directly reduces milk.
• Anything that increases intake at the same nutrient density — better forage quality, consistent delivery, regular push-ups — directly increases milk.

This is why bunk management is one of the highest-leverage interventions on a dairy. A University of Guelph study of 22 Ontario herds (Sova et al. 2013, Journal of Dairy Science) found herds feeding twice a day averaged 4.4 lb more milk per cow per day than herds feeding once; an association across farms, not a controlled trial. In a Spanish study of 47 herds on the same ration (Bach et al. 2008, Journal of Dairy Science), herds that pushed up feed averaged 63.7 lb of milk per cow per day against 55 lb for herds that did not; the number of push-ups made no difference. Both point to the same lever: keeping feed in front of cows so they eat more dry matter.

DMI calculations should always be on a dry matter basis, not as-fed. A cow eating 100 lbs of corn silage as-fed at 35% DM is consuming 35 lbs DM — not 100 lbs of feed.