How mycotoxins affect Chicken health

Mycotoxins such as aflatoxins, fumonisins and zearalenone are by far the most common among poultry today.

Mycotoxins are naturally occurring toxic chemicals produced by moulds and fungi.

They are found mainly in raw maize, corn, cakes, nuts, and other cereal crops used in animal and human feed production.

They are introduced into chickens through the contaminated feed they consume. The toxins affect all poultry species, interfering with their health, performance, and productivity.

Depending on the target organs affected in the chickens, the toxins will destroy the liver, kidneys, nerves and the outer skin of the affected birds.

Mycotoxins such as aflatoxins, fumonisins and zearalenone are by far the most common among poultry today. Moulds and fungi tend to grow during the post-harvest period, especially during the storage of crops in highly humid conditions. Farmers then deliver this contaminated maize to millers for further processing into either human or animal feed. All raw materials used in the formulation mix must be free from any mouldy growth. In an ideal world, no mycotoxins should be allowed in animal feed. However, in real life, traces of mycotoxins occur because of contamination of raw feedstuff like maize, cottonseed, peanut, corn, sunflower cake, wheat bran all components of final feed.

The maximum level of these toxins generally allowed in the industry should not exceed 10 parts per billion. Feeding birds on a diet with higher levels of mycotoxins can result in the birds refusing to eat such contaminated feed at all, resulting in an immediate drop in growth or production.

If they end up consuming such feed, it suppresses their immunity against diseases. Aflatoxins, which are the main problem in this part of the world have been demonstrated to be carcinogenic (can cause cancer) and tend to cause damage to the livers in both humans and animals. The toxins are known to cause a drop in the tissue levels of Vitamin B, Pantothenic acid and choline in the plasma, liver, and bile of chickens. This results in poor health, immunosuppression, poor production, un-thriftiness, and ultimately death. One of the major concerns of mycotoxins fed to food animals like poultry is the ability to concentrate these toxins in chicken muscles, liver, eggs, and tissues, which when consumed by humans may result in poor health. Farmers are likely to encounter loss when birds are fed with contaminated feed from suppliers who do not take feed contamination seriously. In mild exposure cases, the birds will experience reduced feed intake, leading to reduced growth rates and low daily weight gain in meat birds. In laying flocks, toxins will destroy the reproductive system of such birds, leading to a poor or complete cessation of egg production.

[Dr Messo is the company veterinarian, Kenchic; [e-mail]]