Feed safety and preservation: moulds, mycotoxins and oxidation

Feed preservatives hold back whatever degrades feed while it waits: in a silo, a ship’s hold, a bag or a farm bin. The feed safety and preservation category brings together three families of tools, because feed deteriorates in three ways that have neither the same cause nor the same answer.

Moulds and yeasts grow when available water, warmth and time come together. They consume the feed, make it heat up, and leave it smelling musty and caked. Mycotoxins are molecules produced by some moulds, in the field as well as in storage: invisible and odourless, they usually arrive with the raw material. Oxidation attacks fats, oils, vitamins and pigments: a chain reaction that starts in the fat tank and carries on in the premix.

Each of these risks can be measured, and the measurement is what decides the tool and its rate. This page sets out what each platform does, what it works alongside, and how to choose.

For a mould inhibitor, you follow the feed: moisture and water activity at manufacture, storage temperature, yeast and mould counts over the weeks, and the real time between the mill and the last feeding.

For a mycotoxin binder, you follow the raw material: which toxins, at what levels, in which lots. Aflatoxins, deoxynivalenol (DON), zearalenone, fumonisins, ochratoxin A: they do not come from the same moulds or the same raw materials, and they do not all bind equally easily to a clay.

In both cases, comparing two products means a protocol written in advance, with a control: without one, no trial tells you anything.

No raw material arrives the same twice: maize whose moisture changes from one truck to the next, a meal whose origin changes, a recovered fat that is more or less unsaturated. Overdosing as a precaution means paying for a risk you have not measured; underdosing to protect formula cost means the additive does nothing.

A well-taken sample matters as much as the analysis, because mycotoxins are not spread evenly through a lot. Results are then read against your own thresholds: the regulatory values of the destination country, your customers’ specifications, your internal limits.

Send us your results: we read them with you and turn them into a grade and a rate. For mycotoxins: assessment tool available to our customers, on request. How we work, from analysis to recommendation, is set out in How we work.

• Moisture and water activity decide the mould inhibitor rate.
• The contamination profile decides the mycotoxin binder grade.
• Fat content and unsaturation decide the antioxidant rate.

Fat oxidation starts with no smell and no colour change: the first products are invisible, and the rancid note comes later, when part of the value is already gone. Heat, oxygen, the metals in the premix, copper and iron above all, and the unsaturation of the fat all speed up the reaction.

An antioxidant extends the period during which the fat stays intact; it does not repair a fat that has already oxidised. Hence two rules: apply it early, in the premix or at the mixer; calculate its rate on the fat, not on the tonne of feed.

With or without ethoxyquin: the destination market chooses the line, not the animal. Linkatiox comes in both.

Fish feed preservatives have to answer two risks at once: highly unsaturated fish oils, which oxidise fast, and storage that is often hot and humid, in bags, next to the ponds. A fish feed therefore needs an antioxidant dosed on its fat and, depending on its moisture and storage time, a mould inhibitor.

Linkafix, Linkamold and Linkatiox are all used in aquaculture; the grade and the rate are chosen on your formula and your climate.