Mycotoxin and mould growth in dairy feed can lead to lower milk production, poor animal health and reduced profits.
This impact on production is not a new discovery for dairy producers, but there certainly is a growing awareness of the problem, says North Carolina State University professor emeritus Dr. Lon Whitlow. “A large part of it is we’re simply learning more about mycotoxins and the potential roll they play in cow performance problems that have been difficult to explain.”
Whitlow joins Bernard Tobin on this episode of RealAgriculture Dairy School to share insights on how producers can limit mould and mycotoxin problems in their herds. When it comes to corn silage, Whitlow says mould management starts with seed genetics and reducing plant stress. “I really feel that we need to put more fungal resistance in our crops. We have the mechanism to do that with new genetics.”
See related: Dairy School: How to make great corn silage
Fungicides are also proving they can play a key role. “Research would indicate that if you do have a mould problem, fungicides are extremely effective,” says Whitlow. “In some areas of the US, where there are mould problems, fungicides are recommended across the board.”
Another area Whillow says producers should focus on is silage storage. “Wet feeds are one of the big problems. With silage, we do reduce the pH, increase acidity and inhibit mould growth, but penicillium moulds will grow at a low pH, so even with that process we may see some mould growth in the silage.”
This means producers have to be extra vigilant when packing and feeding out silage. “We have to keep air away from the silage—pack the silage very tightly, cover it well and manage the feeding face.” Whitlow recommends feeding a foot a day off the face to stay ahead of mould growth that’s promoted by air infiltration.
In the interview, Whitlow highlights the importance of feeding additional protein and energy. “When we look at microbial growth in the rumen, this is where the cow gets a lot of their protein,” he explains. “With mycotoxins in the feed, we don’t get the microbes growing in the rumen. We get less protein production in the cow, so we basically have a protein deficiency.” Producers can manage this challenge by supplementing protein to increase the metabolizable flow to the cow’s gut.
Whitlow also discusses new products such as immune modulators. These products are important because mycotoxins suppress immunity in the cow and increase incidents of disease and sickness. “To maintain a good, robust immunity level we want to use these immune stimulant products in the presence of mycotoxins,” he adds.