Feed & Livestock Nutrition Metrics in

When you add a new feedstuff or set up livestock requirements in Pasture.io, you’ll notice seven key nutrition metrics. Below is a practical guide to what each value means, the usual units, why it matters in day-to-day grazing decisions, and how Pasture.io treats the number.

Dry Matter (DM)

What it is	The portion of feed remaining once all moisture is removed.
Unit shown in Pio	% of the fresh weight (e.g. 18 % DM for lush spring pasture).
Why it matters	Rations are balanced on a dry-matter basis so you can compare apples with apples—wet silage to dry hay, fresh grass to concentrates.
Tip in Pio	Enter DM as a percentage of fresh weight; Pio converts all other nutrients to a per-kg-DM basis behind the scenes. Note: pasture mass figures in Pio are already expressed on a 100 % DM basis, so record the DM% for pasture as 100.

Neutral Detergent Fibre (NDF)

What it is	Cell-wall fibre (hemicellulose + cellulose + lignin).
Unit	% of DM
Why it matters	Because NDF is closely linked to gut-fill, it is often a better predictor of how much forage an animal can consume in a day than DM% alone. Using NDF helps you size the daily ration so your animals don’t go hungry.
In the app	Pio estimates gut-fill by tracking each mob’s NDF intake relative to live-weight, alerting you when intake nears capacity so you can shorten the grazing interval or add a more digestible feed.

Metabolisable Energy (ME)

What it is	Energy actually available to the animal after faecal, urinary, and gas losses.
Unit	Megajoules per kg DM (MJ ME/kg DM)
Why it matters	Drives milk yield and live-weight gain. For dairy cows, high-quality spring pasture may test at 11–12 MJ/kg DM; autumn or stalky material can drop below 9 MJ.
In the app	When you enter ME, Pio totals the megajoules offered versus required and flags any deficit or surplus. You can change the energy unit (e.g. MJ or Mcal) in Farm Settings.

Crude Protein (CP)

What it is	Total nitrogen × 6.25 – a rough estimate of true protein.
Unit	% of DM
Why it matters	Essential for rumen microbes and animal growth. Pasture often supplies excess CP in spring (>23 % DM), which can limit utilisation of pricey supplements.
In the app	Pio balances CP against animal requirements and shows when protein supplementation (e.g. cottonseed, canola meal, etc) is justified—or not.

Rumen Degradable Protein (RDP)

What it is	Portion of CP broken down in the rumen into ammonia for microbes.
Unit	% of CP or g/kg DM
Why it matters	Adequate RDP keeps microbes fermenting fibre efficiently; too much wastes nitrogen.
In the app	If you leave RDP blank, Pio assumes typical values based on feed class, but editing it gives more precise balance calculations.

Undegradable Protein (UDP)

What it is	Portion of CP that bypasses the rumen and is digested in the small intestine (also called RUP or “bypass protein”).
Unit	% of CP or g/kg DM
Why it matters	Supplies essential amino acids directly to the animal—critical for high-yield dairy cows or fast-growing young stock.
In the app	Pio sums UDP across the diet and flags when low-bypass feeds (e.g. young ryegrass) dominate, so you can add a protected protein source if needed.

Starch

What it is	Readily fermentable carbohydrate stored in grains and some forages.
Unit	% of DM
Why it matters	Provides quick energy for milk or growth but excess can upset rumen pH. Aim for a balanced starch-to-fibre ratio.
In the app	Use Pio’s ration graph to keep starch within recommended limits—typically below 15 % of total DM for pasture-based herds, depending on production goals.

This article explains how Pasture.io displays and uses nutrition data; for ration formulation or animal-health decisions, please seek advice from a qualified ruminant nutritionist or veterinarian.

Feed & Livestock Nutrition Metrics in—What Each Value Means

A concise reference to DM, NDF, ME, CP, RDP, UDP and Starch—covering what, why, and how in Pio for fine-tune rations with confidence.