Trace minerals may help aflatoxin-exposed cows

August 01, 2018

Aflatoxin, a naturally occurring toxin created by mold growth on crops, is one of the most troublesome mycotoxins in the world. Its presence above safe levels in human food and animal feed is harmful to the health of those who consume it, and may be responsible for staggeringly high liver cancer rates in many African countries. Exposure in livestock can drastically decrease productivity.

A huge part of preventing mycotoxins from entering the food supply is rigorous testing of grains to make sure they’re clean. At the same time, researchers are constantly looking for ways to mitigate its effects when it is consumed.

Recently, researchers from the University of Illinois investigated the potential of injecting trace minerals (certain types of natural minerals that help the body function better) to reduce aflatoxin damage in dairy cows — and yielded promising results.

After consuming large amounts of aflatoxin-contaminated feed, dairy cows become lethargic. They eat and grow less, their immune system malfunctions, contributing to a decrease in milk production. Aflatoxin is a carcinogen and can lead to serious liver damage if exposure is prolonged. Some of the symptoms are linked to oxidative stress, which happens when free radicals (unstable atoms) damage living cells.

The researchers administered aflatoxin-exposed dairy cows with a commercially available trace mineral formulation twice, about a month apart. The cows were then challenged with a dose of aflatoxin-contaminated feed. Compared to aflatoxin-exposed cows that hadn’t received the injection, the group’s livers were found to have higher concentrations of the minerals selenium and iron, and increased activity of the free-radical-neutralizing enzyme glutathione peroxidase. Cows that hadn’t been injected with trace minerals had more liver inflammation and lower feed efficiencies.

“If we’re providing enough trace minerals to manufacture more detoxifying enzymes, the liver has a better chance of fighting the aflatoxin,” said lead author Russell Pate. “As we had hypothesized, supplying cows with trace minerals via injection, independent of minerals ingested in the feed, resulted in an improved immune response and reduced oxidative stress when cows were challenged with aflatoxin.”

And although milk production is lowered in aflatoxin-exposed cows, any milk they do produce can contain metabolites of aflatoxin. The researchers tested milk samples for Aflatoxin M1 and found it still present in all milk samples from cows involved, but that wasn’t unexpected.

“To stop transference to the milk, you have to first identify the source of the aflatoxin and avoid feeding it. But sometimes, you just can’t,” said co-author Phil Cardoso. “In those cases, we are showing for the first time that an injectable trace mineral will provide a benefit.”

Category: Agriculture