Drought-stressed maize is more likely to present mycotoxin risk

• Difficult conditions for forage maize 

• Keep watch for mycotoxin problem

Dairy farmers are being warned of a heightened mycotoxin risk when feeding maize forage this autumn and winter.

Hot summer weather means many maize forage crops were grown under drought stressed conditions – increasing the likelihood of in-field mycotoxins developing, says Wynnstay dairy specialist Beth Parry.

“With potentially limited forage stocks following a difficult growing season, farmers are going to need to maximise feed utilisation and digestion to ensure performance isn’t impacted too greatly this winter,” she says.

“In-field mycotoxins are more likely to be present in silages if the crop experienced any kind of stress, such as growing in drought conditions, because moulds and fungi will have had more opportunity to take hold and produce mycotoxins.”

Mould and fungi

Ms Parry recommends farmers consider the impact of extreme weather during the growing season on their maize crops. “If a maize plant was under stress while it was tasseling, that will have added to the risk of in-field mycotoxins developing.

“Unfortunately, there’s no way to overcome the fact that stressful growing conditions increase the likelihood of moulds and fungi moving in and producing mycotoxins, which then remain present in the forage once it’s in the clamp.”

Feeding mycotoxins to cows can trigger a range of herd health problems, including loose muck, poor fertility, swollen hocks, elevated cell counts, impaired rumen function and a reduction in daily milk production.

“Essentially, any unexplained signs of poor health or performance can potentially be caused by presence of mycotoxins in forage,” says Ms Parry.

“If you’re aware there’s a risk of mycotoxin contamination, but have to feed the forage due to limited stocks, the best option is to add a mycotoxin binder to prevent the negative impacts on your herd.”

There are more than 400 mycotoxin types which can cause health issues in dairy cows. But a broad-spectrum mycotoxin binder will lock up most mycotoxins before they are absorbed by the cow, allowing them to pass out in the muck without causing harm.

“There are some mycotoxins which can’t be irreversibly bound, so need to be transformed or degraded to prevent them from causing damage.

“Restore5+ contains yeast extracts which trigger these bio-transformations, enabling key mycotoxins to be bound and excreted. It can also prevent oxidative stress, restore liver function and stimulate an immune response, improving resilience to disease.”.

Including a mycotoxin binder into the ration costs about 10p per cow per day, says Mrs Parry.