Sulphur (S)
A nutrient at normal levels and a neurological hazard well above them — and the co-factor that turns adequate copper into deficient copper.
Often searched as PEM, polioencephalomalacia, high sulphur feed.
What it changes in the tools
- Dietary sulphur (PEM watch)
- These are DIET figures, not per-feed ones. Watch at 0.40% of diet DM — the general hazard line, set above normal NZ pasture (~0.33%) so grass does not cry wolf. Risk at 0.50%, the high-forage maximum tolerable. The practical mitigation is to introduce high-sulphur feeds gradually and keep effective fibre up, rather than to avoid them. Covers feed sulphur only: high-sulphate stock or bore water is a common trigger the engine cannot see. (Cattle-derived; PEM in sheep and goats is more often thiamine-driven.)
- Source: NRC (2005) Mineral Tolerance of Animals for the 0.50% high-forage maximum tolerable; NASEM Beef (2016). The 0.40% watch is our own earlier line, set above NZ pasture.
- Copper lock-up
- Sulphur above 0.4% DM compounds molybdenum’s antagonism of copper.
- Source: Grace & Knowles (2012).
Which feeds carry the most sulphur
From the cited composition of every feed in our library, as a percentage of dry matter. Useful when the answer is a feed change rather than a mineral product.
| Feed | % of dry matter |
|---|---|
| Canola meal | 0.83% |
| Chicory | 0.63% |
| Distillers grains (wheat) Wheat distillers grains run 34–40% protein depending on the process and any blending. Check the spec of what you’re actually buying. | 0.6% |
| Forage rape New Zealand leafy rape is high-energy and modest-protein. Overseas figures for rape read the opposite way round, so don’t be thrown if you find one. | 0.49% |
| Sunflower meal | 0.44% |
| Molasses (cane) | 0.4% |
Mineral products, if you're dosing
Dosed in grams per head per day rather than fed by the kilogram — a different decision from changing the diet, so they are listed apart from the feeds.
| Feed | % of dry matter |
|---|---|
| Gypsum (calcium sulphate) An anionic salt, fed pre-calving to pull DCAD down. Sulphate acidifies less per unit than chloride, so don’t read its DCAD figure as equivalent to calcium chloride’s. | 16% |
Read it for your farm
Build the diet and it works the mineral balance out for you — including the indices below.
These are published reference bands, not a diagnosis. Mineral deficiencies and toxicities are diagnosed from the animal — blood, liver or tissue — not from a pasture test alone, and the treatment rates are veterinary decisions. Talk to your vet before dosing stock.