Mycotoxins in Poultry Feed and How to Counter Them

Mycotoxins are not a single disease but a family of poisons produced by moulds on maize, soybean meal and cottonseed when storage goes wrong. In Egypt, Delta humidity and summer heat turn a feed bag into a growth medium for Aspergillus and Fusarium once moisture passes 14 percent. The result is rarely sudden death. It appears instead as uneven growth, repeated diarrhoea, a pale enlarged liver, fewer eggs and a poor response to vaccination. Farmers who chase the cheapest feed are the ones most exposed to these silent losses.

The main mycotoxins and where they come from

Aflatoxin B1 is the most damaging and widespread mycotoxin in Egypt. It is produced by Aspergillus flavus growing on maize, soya and groundnut meal when moisture is high. It targets the liver, causing enlargement and pallor, and suppresses immunity so vaccines appear to fail. Ochratoxin attacks the kidneys and affects shell quality, T-2 causes mouth ulcers and feed refusal, fumonisin is linked to nervous signs and lung oedema, and zearalenone causes reproductive problems and prolapse in breeder flocks.

Contamination starts in the field and does not end in the store. Rain-damaged maize, broken grains, cottonseed meal and old feed left in an unventilated silo are all suitable media for mould. Delta farmers often receive feed with hard lumps or a musty smell, yet the smell fades while the toxins remain. Storing bags on the floor or against a wall lets moisture seep in from concrete and completes the problem.

What the farmer actually sees

The real loss from mycotoxins is not mass mortality but an uneven flock. You see smaller birds, ruffled feathers, pale combs, recurring watery droppings and lower feed intake. In layers, production slides and shells get thinner; in breeders, hatchability falls. Many farmers treat these signs with repeated antibiotics and see no result, because the cause was never bacterial.

At post-mortem the liver is enlarged, pale yellow or greyish and crumbles easily, with pale kidneys and urate deposits. Ulcers may appear in the mouth and oesophagus, and small haemorrhages on muscles. This picture resembles fatty liver and some drug toxicities, so the eye alone cannot decide; diagnosis needs feed analysis and a feeding history reviewed with your veterinarian.

Diagnosis: beyond the naked eye

Diagnosis starts with a representative feed sample taken from several bags, not just one, and sent to an accredited laboratory for toxin testing. Keep the batch number and delivery date, because a repeat result on the same batch proves the problem and supports a claim against the supplier. Measuring feed moisture with a simple meter on arrival is a step good farms never skip.

Visible mould is not required for toxins to be present, and the disappearance of mould does not remove them, because the compounds survive after the fungus dies. The greater danger is chronic exposure to low levels: it does not kill birds but steals every point of feed conversion and makes vaccines look ineffective. Routine testing therefore matters more than judging colour or smell.

Prevention, storage and toxin binders

Prevention begins with buying from a licensed feed mill with a known source, not from informal mixers. Buy three to four weeks of feed at a time in summer, stack bags on wooden pallets away from walls, keep the store ventilated and use the oldest batch first. Clean silos between loads and never top up new feed over old residues at the bottom.

Mould inhibitors such as propionic acid protect feed during storage, while binders work in the gut by trapping toxins and limiting absorption; bentonite, yeast cell wall and activated charcoal are the common choices. These products do not repair feed that is already spoiled and do not excuse using a contaminated batch. Liver support with vitamins A and E plus selenium is given only under veterinary supervision. Clean drinking equipment is listed in our poultry supplies, veterinary tools under medical supplies, and registered support such as poultry vitamins should be chosen with your vet.

• Test feed moisture on arrival and reject loads above 13 percent.
• Stack bags on pallets and never against the walls.
• Use feed within three to four weeks during the summer.
• Clean silos and conveying lines between every batch.
• Reject any batch with a musty smell or hard lumps instead of treating it.
• Ask your veterinarian before adding a binder or vitamin pack.

Conclusion

Mycotoxins are controlled by buying well, storing dry and testing often. Cheap feed that damages the liver costs more than it saves. Keep moisture low, rotate stock, use binders correctly and let your veterinarian confirm any suspicion before you treat the flock.

This article is general guidance and is not a substitute for examining your animal by a licensed veterinarian. In emergencies, contact your vet immediately.